SkGpuDevice.cpp revision a3264e53ee3f3c5d6a2c813df7e44b5b96d207f2 
1/*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "SkGpuDevice.h"
9
10#include "effects/GrBicubicEffect.h"
11#include "effects/GrDashingEffect.h"
12#include "effects/GrTextureDomain.h"
13#include "effects/GrSimpleTextureEffect.h"
14
15#include "GrContext.h"
16#include "GrBitmapTextContext.h"
17#include "GrDistanceFieldTextContext.h"
18#include "GrLayerCache.h"
19#include "GrPictureUtils.h"
20
21#include "SkGrTexturePixelRef.h"
22
23#include "SkBounder.h"
24#include "SkDeviceImageFilterProxy.h"
25#include "SkDrawProcs.h"
26#include "SkGlyphCache.h"
27#include "SkImageFilter.h"
28#include "SkMaskFilter.h"
29#include "SkPathEffect.h"
30#include "SkPicture.h"
31#include "SkPicturePlayback.h"
32#include "SkRRect.h"
33#include "SkStroke.h"
34#include "SkSurface.h"
35#include "SkTLazy.h"
36#include "SkUtils.h"
37#include "SkVertState.h"
38#include "SkErrorInternals.h"
39
40#define CACHE_COMPATIBLE_DEVICE_TEXTURES 1
41
42#if 0
43    extern bool (*gShouldDrawProc)();
44    #define CHECK_SHOULD_DRAW(draw, forceI)                     \
45        do {                                                    \
46            if (gShouldDrawProc && !gShouldDrawProc()) return;  \
47            this->prepareDraw(draw, forceI);                    \
48        } while (0)
49#else
50    #define CHECK_SHOULD_DRAW(draw, forceI) this->prepareDraw(draw, forceI)
51#endif
52
53// This constant represents the screen alignment criterion in texels for
54// requiring texture domain clamping to prevent color bleeding when drawing
55// a sub region of a larger source image.
56#define COLOR_BLEED_TOLERANCE 0.001f
57
58#define DO_DEFERRED_CLEAR()             \
59    do {                                \
60        if (fNeedClear) {               \
61            this->clear(SK_ColorTRANSPARENT); \
62        }                               \
63    } while (false)                     \
64
65///////////////////////////////////////////////////////////////////////////////
66
67#define CHECK_FOR_ANNOTATION(paint) \
68    do { if (paint.getAnnotation()) { return; } } while (0)
69
70///////////////////////////////////////////////////////////////////////////////
71
72
73class SkGpuDevice::SkAutoCachedTexture : public ::SkNoncopyable {
74public:
75    SkAutoCachedTexture()
76        : fDevice(NULL)
77        , fTexture(NULL) {
78    }
79
80    SkAutoCachedTexture(SkGpuDevice* device,
81                        const SkBitmap& bitmap,
82                        const GrTextureParams* params,
83                        GrTexture** texture)
84        : fDevice(NULL)
85        , fTexture(NULL) {
86        SkASSERT(NULL != texture);
87        *texture = this->set(device, bitmap, params);
88    }
89
90    ~SkAutoCachedTexture() {
91        if (NULL != fTexture) {
92            GrUnlockAndUnrefCachedBitmapTexture(fTexture);
93        }
94    }
95
96    GrTexture* set(SkGpuDevice* device,
97                   const SkBitmap& bitmap,
98                   const GrTextureParams* params) {
99        if (NULL != fTexture) {
100            GrUnlockAndUnrefCachedBitmapTexture(fTexture);
101            fTexture = NULL;
102        }
103        fDevice = device;
104        GrTexture* result = (GrTexture*)bitmap.getTexture();
105        if (NULL == result) {
106            // Cannot return the native texture so look it up in our cache
107            fTexture = GrLockAndRefCachedBitmapTexture(device->context(), bitmap, params);
108            result = fTexture;
109        }
110        return result;
111    }
112
113private:
114    SkGpuDevice* fDevice;
115    GrTexture*   fTexture;
116};
117
118///////////////////////////////////////////////////////////////////////////////
119
120struct GrSkDrawProcs : public SkDrawProcs {
121public:
122    GrContext* fContext;
123    GrTextContext* fTextContext;
124    GrFontScaler* fFontScaler;  // cached in the skia glyphcache
125};
126
127///////////////////////////////////////////////////////////////////////////////
128
129static SkBitmap::Config grConfig2skConfig(GrPixelConfig config, bool* isOpaque) {
130    switch (config) {
131        case kAlpha_8_GrPixelConfig:
132            *isOpaque = false;
133            return SkBitmap::kA8_Config;
134        case kRGB_565_GrPixelConfig:
135            *isOpaque = true;
136            return SkBitmap::kRGB_565_Config;
137        case kRGBA_4444_GrPixelConfig:
138            *isOpaque = false;
139            return SkBitmap::kARGB_4444_Config;
140        case kSkia8888_GrPixelConfig:
141            // we don't currently have a way of knowing whether
142            // a 8888 is opaque based on the config.
143            *isOpaque = false;
144            return SkBitmap::kARGB_8888_Config;
145        default:
146            *isOpaque = false;
147            return SkBitmap::kNo_Config;
148    }
149}
150
151/*
152 * GrRenderTarget does not know its opaqueness, only its config, so we have
153 * to make conservative guesses when we return an "equivalent" bitmap.
154 */
155static SkBitmap make_bitmap(GrContext* context, GrRenderTarget* renderTarget) {
156    bool isOpaque;
157    SkBitmap::Config config = grConfig2skConfig(renderTarget->config(), &isOpaque);
158
159    SkBitmap bitmap;
160    bitmap.setConfig(config, renderTarget->width(), renderTarget->height(), 0,
161                     isOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
162    return bitmap;
163}
164
165SkGpuDevice* SkGpuDevice::Create(GrSurface* surface, unsigned flags) {
166    SkASSERT(NULL != surface);
167    if (NULL == surface->asRenderTarget() || NULL == surface->getContext()) {
168        return NULL;
169    }
170    if (surface->asTexture()) {
171        return SkNEW_ARGS(SkGpuDevice, (surface->getContext(), surface->asTexture(), flags));
172    } else {
173        return SkNEW_ARGS(SkGpuDevice, (surface->getContext(), surface->asRenderTarget(), flags));
174    }
175}
176
177SkGpuDevice::SkGpuDevice(GrContext* context, GrTexture* texture, unsigned flags)
178    : SkBitmapDevice(make_bitmap(context, texture->asRenderTarget())) {
179    this->initFromRenderTarget(context, texture->asRenderTarget(), flags);
180}
181
182SkGpuDevice::SkGpuDevice(GrContext* context, GrRenderTarget* renderTarget, unsigned flags)
183    : SkBitmapDevice(make_bitmap(context, renderTarget)) {
184    this->initFromRenderTarget(context, renderTarget, flags);
185}
186
187void SkGpuDevice::initFromRenderTarget(GrContext* context,
188                                       GrRenderTarget* renderTarget,
189                                       unsigned flags) {
190    fDrawProcs = NULL;
191
192    fContext = context;
193    fContext->ref();
194
195    bool useDFFonts = !!(flags & kDFFonts_Flag);
196    fMainTextContext = SkNEW_ARGS(GrDistanceFieldTextContext, (fContext, fLeakyProperties,
197                                                               useDFFonts));
198    fFallbackTextContext = SkNEW_ARGS(GrBitmapTextContext, (fContext, fLeakyProperties));
199
200    fRenderTarget = NULL;
201    fNeedClear = flags & kNeedClear_Flag;
202
203    SkASSERT(NULL != renderTarget);
204    fRenderTarget = renderTarget;
205    fRenderTarget->ref();
206
207    // Hold onto to the texture in the pixel ref (if there is one) because the texture holds a ref
208    // on the RT but not vice-versa.
209    // TODO: Remove this trickery once we figure out how to make SkGrPixelRef do this without
210    // busting chrome (for a currently unknown reason).
211    GrSurface* surface = fRenderTarget->asTexture();
212    if (NULL == surface) {
213        surface = fRenderTarget;
214    }
215
216    SkImageInfo info;
217    surface->asImageInfo(&info);
218    SkPixelRef* pr = SkNEW_ARGS(SkGrPixelRef, (info, surface, SkToBool(flags & kCached_Flag)));
219
220    this->setPixelRef(pr)->unref();
221}
222
223SkGpuDevice* SkGpuDevice::Create(GrContext* context, const SkImageInfo& origInfo,
224                                 int sampleCount) {
225    if (kUnknown_SkColorType == origInfo.colorType() ||
226        origInfo.width() < 0 || origInfo.height() < 0) {
227        return NULL;
228    }
229
230    SkImageInfo info = origInfo;
231    // TODO: perhas we can loosen this check now that colortype is more detailed
232    // e.g. can we support both RGBA and BGRA here?
233    if (kRGB_565_SkColorType == info.colorType()) {
234        info.fAlphaType = kOpaque_SkAlphaType;  // force this setting
235    } else {
236        info.fColorType = kN32_SkColorType;
237        if (kOpaque_SkAlphaType != info.alphaType()) {
238            info.fAlphaType = kPremul_SkAlphaType;  // force this setting
239        }
240    }
241
242    GrTextureDesc desc;
243    desc.fFlags = kRenderTarget_GrTextureFlagBit;
244    desc.fWidth = info.width();
245    desc.fHeight = info.height();
246    desc.fConfig = SkImageInfo2GrPixelConfig(info);
247    desc.fSampleCnt = sampleCount;
248
249    SkAutoTUnref<GrTexture> texture(context->createUncachedTexture(desc, NULL, 0));
250    if (!texture.get()) {
251        return NULL;
252    }
253
254    return SkNEW_ARGS(SkGpuDevice, (context, texture.get()));
255}
256
257SkGpuDevice::~SkGpuDevice() {
258    if (fDrawProcs) {
259        delete fDrawProcs;
260    }
261
262    delete fMainTextContext;
263    delete fFallbackTextContext;
264
265    // The GrContext takes a ref on the target. We don't want to cause the render
266    // target to be unnecessarily kept alive.
267    if (fContext->getRenderTarget() == fRenderTarget) {
268        fContext->setRenderTarget(NULL);
269    }
270
271    if (fContext->getClip() == &fClipData) {
272        fContext->setClip(NULL);
273    }
274
275    SkSafeUnref(fRenderTarget);
276    fContext->unref();
277}
278
279///////////////////////////////////////////////////////////////////////////////
280
281void SkGpuDevice::makeRenderTargetCurrent() {
282    DO_DEFERRED_CLEAR();
283    fContext->setRenderTarget(fRenderTarget);
284}
285
286///////////////////////////////////////////////////////////////////////////////
287
288bool SkGpuDevice::onReadPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
289                               int x, int y) {
290    DO_DEFERRED_CLEAR();
291
292    // TODO: teach fRenderTarget to take ImageInfo directly to specify the src pixels
293    GrPixelConfig config = SkImageInfo2GrPixelConfig(dstInfo);
294    if (kUnknown_GrPixelConfig == config) {
295        return false;
296    }
297
298    uint32_t flags = 0;
299    if (kUnpremul_SkAlphaType == dstInfo.alphaType()) {
300        flags = GrContext::kUnpremul_PixelOpsFlag;
301    }
302    return fContext->readRenderTargetPixels(fRenderTarget, x, y, dstInfo.width(), dstInfo.height(),
303                                            config, dstPixels, dstRowBytes, flags);
304}
305
306bool SkGpuDevice::onWritePixels(const SkImageInfo& info, const void* pixels, size_t rowBytes,
307                                int x, int y) {
308    // TODO: teach fRenderTarget to take ImageInfo directly to specify the src pixels
309    GrPixelConfig config = SkImageInfo2GrPixelConfig(info);
310    if (kUnknown_GrPixelConfig == config) {
311        return false;
312    }
313    uint32_t flags = 0;
314    if (kUnpremul_SkAlphaType == info.alphaType()) {
315        flags = GrContext::kUnpremul_PixelOpsFlag;
316    }
317    fRenderTarget->writePixels(x, y, info.width(), info.height(), config, pixels, rowBytes, flags);
318
319    // need to bump our genID for compatibility with clients that "know" we have a bitmap
320    this->onAccessBitmap().notifyPixelsChanged();
321
322    return true;
323}
324
325const SkBitmap& SkGpuDevice::onAccessBitmap() {
326    DO_DEFERRED_CLEAR();
327    return INHERITED::onAccessBitmap();
328}
329
330void SkGpuDevice::onAttachToCanvas(SkCanvas* canvas) {
331    INHERITED::onAttachToCanvas(canvas);
332
333    // Canvas promises that this ptr is valid until onDetachFromCanvas is called
334    fClipData.fClipStack = canvas->getClipStack();
335}
336
337void SkGpuDevice::onDetachFromCanvas() {
338    INHERITED::onDetachFromCanvas();
339    fClipData.fClipStack = NULL;
340}
341
342// call this every draw call, to ensure that the context reflects our state,
343// and not the state from some other canvas/device
344void SkGpuDevice::prepareDraw(const SkDraw& draw, bool forceIdentity) {
345    SkASSERT(NULL != fClipData.fClipStack);
346
347    fContext->setRenderTarget(fRenderTarget);
348
349    SkASSERT(draw.fClipStack && draw.fClipStack == fClipData.fClipStack);
350
351    if (forceIdentity) {
352        fContext->setIdentityMatrix();
353    } else {
354        fContext->setMatrix(*draw.fMatrix);
355    }
356    fClipData.fOrigin = this->getOrigin();
357
358    fContext->setClip(&fClipData);
359
360    DO_DEFERRED_CLEAR();
361}
362
363GrRenderTarget* SkGpuDevice::accessRenderTarget() {
364    DO_DEFERRED_CLEAR();
365    return fRenderTarget;
366}
367
368///////////////////////////////////////////////////////////////////////////////
369
370SK_COMPILE_ASSERT(SkShader::kNone_BitmapType == 0, shader_type_mismatch);
371SK_COMPILE_ASSERT(SkShader::kDefault_BitmapType == 1, shader_type_mismatch);
372SK_COMPILE_ASSERT(SkShader::kRadial_BitmapType == 2, shader_type_mismatch);
373SK_COMPILE_ASSERT(SkShader::kSweep_BitmapType == 3, shader_type_mismatch);
374SK_COMPILE_ASSERT(SkShader::kTwoPointRadial_BitmapType == 4,
375                  shader_type_mismatch);
376SK_COMPILE_ASSERT(SkShader::kTwoPointConical_BitmapType == 5,
377                  shader_type_mismatch);
378SK_COMPILE_ASSERT(SkShader::kLinear_BitmapType == 6, shader_type_mismatch);
379SK_COMPILE_ASSERT(SkShader::kLast_BitmapType == 6, shader_type_mismatch);
380
381///////////////////////////////////////////////////////////////////////////////
382
383SkBitmap::Config SkGpuDevice::config() const {
384    if (NULL == fRenderTarget) {
385        return SkBitmap::kNo_Config;
386    }
387
388    bool isOpaque;
389    return grConfig2skConfig(fRenderTarget->config(), &isOpaque);
390}
391
392void SkGpuDevice::clear(SkColor color) {
393    SkIRect rect = SkIRect::MakeWH(this->width(), this->height());
394    fContext->clear(&rect, SkColor2GrColor(color), true, fRenderTarget);
395    fNeedClear = false;
396}
397
398void SkGpuDevice::drawPaint(const SkDraw& draw, const SkPaint& paint) {
399    CHECK_SHOULD_DRAW(draw, false);
400
401    GrPaint grPaint;
402    SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
403
404    fContext->drawPaint(grPaint);
405}
406
407// must be in SkCanvas::PointMode order
408static const GrPrimitiveType gPointMode2PrimtiveType[] = {
409    kPoints_GrPrimitiveType,
410    kLines_GrPrimitiveType,
411    kLineStrip_GrPrimitiveType
412};
413
414void SkGpuDevice::drawPoints(const SkDraw& draw, SkCanvas::PointMode mode,
415                             size_t count, const SkPoint pts[], const SkPaint& paint) {
416    CHECK_FOR_ANNOTATION(paint);
417    CHECK_SHOULD_DRAW(draw, false);
418
419    SkScalar width = paint.getStrokeWidth();
420    if (width < 0) {
421        return;
422    }
423
424    if (paint.getPathEffect() && 2 == count && SkCanvas::kLines_PointMode == mode) {
425        if (GrDashingEffect::DrawDashLine(pts, paint, this->context())) {
426            return;
427        }
428    }
429
430    // we only handle hairlines and paints without path effects or mask filters,
431    // else we let the SkDraw call our drawPath()
432    if (width > 0 || paint.getPathEffect() || paint.getMaskFilter()) {
433        draw.drawPoints(mode, count, pts, paint, true);
434        return;
435    }
436
437    GrPaint grPaint;
438    SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
439
440    fContext->drawVertices(grPaint,
441                           gPointMode2PrimtiveType[mode],
442                           SkToS32(count),
443                           (SkPoint*)pts,
444                           NULL,
445                           NULL,
446                           NULL,
447                           0);
448}
449
450///////////////////////////////////////////////////////////////////////////////
451
452void SkGpuDevice::drawRect(const SkDraw& draw, const SkRect& rect,
453                           const SkPaint& paint) {
454    CHECK_FOR_ANNOTATION(paint);
455    CHECK_SHOULD_DRAW(draw, false);
456
457    bool doStroke = paint.getStyle() != SkPaint::kFill_Style;
458    SkScalar width = paint.getStrokeWidth();
459
460    /*
461        We have special code for hairline strokes, miter-strokes, bevel-stroke
462        and fills. Anything else we just call our path code.
463     */
464    bool usePath = doStroke && width > 0 &&
465                   (paint.getStrokeJoin() == SkPaint::kRound_Join ||
466                    (paint.getStrokeJoin() == SkPaint::kBevel_Join && rect.isEmpty()));
467    // another two reasons we might need to call drawPath...
468    if (paint.getMaskFilter() || paint.getPathEffect()) {
469        usePath = true;
470    }
471    if (!usePath && paint.isAntiAlias() && !fContext->getMatrix().rectStaysRect()) {
472#if defined(SHADER_AA_FILL_RECT) || !defined(IGNORE_ROT_AA_RECT_OPT)
473        if (doStroke) {
474#endif
475            usePath = true;
476#if defined(SHADER_AA_FILL_RECT) || !defined(IGNORE_ROT_AA_RECT_OPT)
477        } else {
478            usePath = !fContext->getMatrix().preservesRightAngles();
479        }
480#endif
481    }
482    // until we can both stroke and fill rectangles
483    if (paint.getStyle() == SkPaint::kStrokeAndFill_Style) {
484        usePath = true;
485    }
486
487    if (usePath) {
488        SkPath path;
489        path.addRect(rect);
490        this->drawPath(draw, path, paint, NULL, true);
491        return;
492    }
493
494    GrPaint grPaint;
495    SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
496
497    if (!doStroke) {
498        fContext->drawRect(grPaint, rect);
499    } else {
500        SkStrokeRec stroke(paint);
501        fContext->drawRect(grPaint, rect, &stroke);
502    }
503}
504
505///////////////////////////////////////////////////////////////////////////////
506
507void SkGpuDevice::drawRRect(const SkDraw& draw, const SkRRect& rect,
508                           const SkPaint& paint) {
509    CHECK_FOR_ANNOTATION(paint);
510    CHECK_SHOULD_DRAW(draw, false);
511
512    GrPaint grPaint;
513    SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
514
515    SkStrokeRec stroke(paint);
516    if (paint.getMaskFilter()) {
517        // try to hit the fast path for drawing filtered round rects
518
519        SkRRect devRRect;
520        if (rect.transform(fContext->getMatrix(), &devRRect)) {
521            if (devRRect.allCornersCircular()) {
522                SkRect maskRect;
523                if (paint.getMaskFilter()->canFilterMaskGPU(devRRect.rect(),
524                                            draw.fClip->getBounds(),
525                                            fContext->getMatrix(),
526                                            &maskRect)) {
527                    SkIRect finalIRect;
528                    maskRect.roundOut(&finalIRect);
529                    if (draw.fClip->quickReject(finalIRect)) {
530                        // clipped out
531                        return;
532                    }
533                    if (NULL != draw.fBounder && !draw.fBounder->doIRect(finalIRect)) {
534                        // nothing to draw
535                        return;
536                    }
537                    if (paint.getMaskFilter()->directFilterRRectMaskGPU(fContext, &grPaint,
538                                                                        stroke, devRRect)) {
539                        return;
540                    }
541                }
542
543            }
544        }
545
546    }
547
548    if (paint.getMaskFilter() || paint.getPathEffect()) {
549        SkPath path;
550        path.addRRect(rect);
551        this->drawPath(draw, path, paint, NULL, true);
552        return;
553    }
554
555    fContext->drawRRect(grPaint, rect, stroke);
556}
557
558void SkGpuDevice::drawDRRect(const SkDraw& draw, const SkRRect& outer,
559                              const SkRRect& inner, const SkPaint& paint) {
560    SkStrokeRec stroke(paint);
561    if (stroke.isFillStyle()) {
562
563        CHECK_FOR_ANNOTATION(paint);
564        CHECK_SHOULD_DRAW(draw, false);
565
566        GrPaint grPaint;
567        SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
568
569        if (NULL == paint.getMaskFilter() && NULL == paint.getPathEffect()) {
570            fContext->drawDRRect(grPaint, outer, inner);
571            return;
572        }
573    }
574
575    SkPath path;
576    path.addRRect(outer);
577    path.addRRect(inner);
578    path.setFillType(SkPath::kEvenOdd_FillType);
579
580    this->drawPath(draw, path, paint, NULL, true);
581}
582
583
584/////////////////////////////////////////////////////////////////////////////
585
586void SkGpuDevice::drawOval(const SkDraw& draw, const SkRect& oval,
587                           const SkPaint& paint) {
588    CHECK_FOR_ANNOTATION(paint);
589    CHECK_SHOULD_DRAW(draw, false);
590
591    bool usePath = false;
592    // some basic reasons we might need to call drawPath...
593    if (paint.getMaskFilter() || paint.getPathEffect()) {
594        usePath = true;
595    }
596
597    if (usePath) {
598        SkPath path;
599        path.addOval(oval);
600        this->drawPath(draw, path, paint, NULL, true);
601        return;
602    }
603
604    GrPaint grPaint;
605    SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
606    SkStrokeRec stroke(paint);
607
608    fContext->drawOval(grPaint, oval, stroke);
609}
610
611#include "SkMaskFilter.h"
612#include "SkBounder.h"
613
614///////////////////////////////////////////////////////////////////////////////
615
616// helpers for applying mask filters
617namespace {
618
619// Draw a mask using the supplied paint. Since the coverage/geometry
620// is already burnt into the mask this boils down to a rect draw.
621// Return true if the mask was successfully drawn.
622bool draw_mask(GrContext* context, const SkRect& maskRect,
623               GrPaint* grp, GrTexture* mask) {
624    GrContext::AutoMatrix am;
625    if (!am.setIdentity(context, grp)) {
626        return false;
627    }
628
629    SkMatrix matrix;
630    matrix.setTranslate(-maskRect.fLeft, -maskRect.fTop);
631    matrix.postIDiv(mask->width(), mask->height());
632
633    grp->addCoverageEffect(GrSimpleTextureEffect::Create(mask, matrix))->unref();
634    context->drawRect(*grp, maskRect);
635    return true;
636}
637
638bool draw_with_mask_filter(GrContext* context, const SkPath& devPath,
639                           SkMaskFilter* filter, const SkRegion& clip, SkBounder* bounder,
640                           GrPaint* grp, SkPaint::Style style) {
641    SkMask  srcM, dstM;
642
643    if (!SkDraw::DrawToMask(devPath, &clip.getBounds(), filter, &context->getMatrix(), &srcM,
644                            SkMask::kComputeBoundsAndRenderImage_CreateMode, style)) {
645        return false;
646    }
647    SkAutoMaskFreeImage autoSrc(srcM.fImage);
648
649    if (!filter->filterMask(&dstM, srcM, context->getMatrix(), NULL)) {
650        return false;
651    }
652    // this will free-up dstM when we're done (allocated in filterMask())
653    SkAutoMaskFreeImage autoDst(dstM.fImage);
654
655    if (clip.quickReject(dstM.fBounds)) {
656        return false;
657    }
658    if (bounder && !bounder->doIRect(dstM.fBounds)) {
659        return false;
660    }
661
662    // we now have a device-aligned 8bit mask in dstM, ready to be drawn using
663    // the current clip (and identity matrix) and GrPaint settings
664    GrTextureDesc desc;
665    desc.fWidth = dstM.fBounds.width();
666    desc.fHeight = dstM.fBounds.height();
667    desc.fConfig = kAlpha_8_GrPixelConfig;
668
669    GrAutoScratchTexture ast(context, desc);
670    GrTexture* texture = ast.texture();
671
672    if (NULL == texture) {
673        return false;
674    }
675    texture->writePixels(0, 0, desc.fWidth, desc.fHeight, desc.fConfig,
676                               dstM.fImage, dstM.fRowBytes);
677
678    SkRect maskRect = SkRect::Make(dstM.fBounds);
679
680    return draw_mask(context, maskRect, grp, texture);
681}
682
683// Create a mask of 'devPath' and place the result in 'mask'. Return true on
684// success; false otherwise.
685bool create_mask_GPU(GrContext* context,
686                     const SkRect& maskRect,
687                     const SkPath& devPath,
688                     const SkStrokeRec& stroke,
689                     bool doAA,
690                     GrAutoScratchTexture* mask) {
691    GrTextureDesc desc;
692    desc.fFlags = kRenderTarget_GrTextureFlagBit;
693    desc.fWidth = SkScalarCeilToInt(maskRect.width());
694    desc.fHeight = SkScalarCeilToInt(maskRect.height());
695    // We actually only need A8, but it often isn't supported as a
696    // render target so default to RGBA_8888
697    desc.fConfig = kRGBA_8888_GrPixelConfig;
698    if (context->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
699        desc.fConfig = kAlpha_8_GrPixelConfig;
700    }
701
702    mask->set(context, desc);
703    if (NULL == mask->texture()) {
704        return false;
705    }
706
707    GrTexture* maskTexture = mask->texture();
708    SkRect clipRect = SkRect::MakeWH(maskRect.width(), maskRect.height());
709
710    GrContext::AutoRenderTarget art(context, maskTexture->asRenderTarget());
711    GrContext::AutoClip ac(context, clipRect);
712
713    context->clear(NULL, 0x0, true);
714
715    GrPaint tempPaint;
716    if (doAA) {
717        tempPaint.setAntiAlias(true);
718        // AA uses the "coverage" stages on GrDrawTarget. Coverage with a dst
719        // blend coeff of zero requires dual source blending support in order
720        // to properly blend partially covered pixels. This means the AA
721        // code path may not be taken. So we use a dst blend coeff of ISA. We
722        // could special case AA draws to a dst surface with known alpha=0 to
723        // use a zero dst coeff when dual source blending isn't available.
724        tempPaint.setBlendFunc(kOne_GrBlendCoeff, kISC_GrBlendCoeff);
725    }
726
727    GrContext::AutoMatrix am;
728
729    // Draw the mask into maskTexture with the path's top-left at the origin using tempPaint.
730    SkMatrix translate;
731    translate.setTranslate(-maskRect.fLeft, -maskRect.fTop);
732    am.set(context, translate);
733    context->drawPath(tempPaint, devPath, stroke);
734    return true;
735}
736
737SkBitmap wrap_texture(GrTexture* texture) {
738    SkImageInfo info;
739    texture->asImageInfo(&info);
740
741    SkBitmap result;
742    result.setInfo(info);
743    result.setPixelRef(SkNEW_ARGS(SkGrPixelRef, (info, texture)))->unref();
744    return result;
745}
746
747};
748
749void SkGpuDevice::drawPath(const SkDraw& draw, const SkPath& origSrcPath,
750                           const SkPaint& paint, const SkMatrix* prePathMatrix,
751                           bool pathIsMutable) {
752    CHECK_FOR_ANNOTATION(paint);
753    CHECK_SHOULD_DRAW(draw, false);
754
755    GrPaint grPaint;
756    SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
757
758    // If we have a prematrix, apply it to the path, optimizing for the case
759    // where the original path can in fact be modified in place (even though
760    // its parameter type is const).
761    SkPath* pathPtr = const_cast<SkPath*>(&origSrcPath);
762    SkTLazy<SkPath> tmpPath;
763    SkTLazy<SkPath> effectPath;
764
765    if (prePathMatrix) {
766        SkPath* result = pathPtr;
767
768        if (!pathIsMutable) {
769            result = tmpPath.init();
770            pathIsMutable = true;
771        }
772        // should I push prePathMatrix on our MV stack temporarily, instead
773        // of applying it here? See SkDraw.cpp
774        pathPtr->transform(*prePathMatrix, result);
775        pathPtr = result;
776    }
777    // at this point we're done with prePathMatrix
778    SkDEBUGCODE(prePathMatrix = (const SkMatrix*)0x50FF8001;)
779
780    SkStrokeRec stroke(paint);
781    SkPathEffect* pathEffect = paint.getPathEffect();
782    const SkRect* cullRect = NULL;  // TODO: what is our bounds?
783    if (pathEffect && pathEffect->filterPath(effectPath.init(), *pathPtr, &stroke,
784                                             cullRect)) {
785        pathPtr = effectPath.get();
786        pathIsMutable = true;
787    }
788
789    if (paint.getMaskFilter()) {
790        if (!stroke.isHairlineStyle()) {
791            SkPath* strokedPath = pathIsMutable ? pathPtr : tmpPath.init();
792            if (stroke.applyToPath(strokedPath, *pathPtr)) {
793                pathPtr = strokedPath;
794                pathIsMutable = true;
795                stroke.setFillStyle();
796            }
797        }
798
799        // avoid possibly allocating a new path in transform if we can
800        SkPath* devPathPtr = pathIsMutable ? pathPtr : tmpPath.init();
801
802        // transform the path into device space
803        pathPtr->transform(fContext->getMatrix(), devPathPtr);
804
805        SkRect maskRect;
806        if (paint.getMaskFilter()->canFilterMaskGPU(devPathPtr->getBounds(),
807                                                    draw.fClip->getBounds(),
808                                                    fContext->getMatrix(),
809                                                    &maskRect)) {
810            // The context's matrix may change while creating the mask, so save the CTM here to
811            // pass to filterMaskGPU.
812            const SkMatrix ctm = fContext->getMatrix();
813
814            SkIRect finalIRect;
815            maskRect.roundOut(&finalIRect);
816            if (draw.fClip->quickReject(finalIRect)) {
817                // clipped out
818                return;
819            }
820            if (NULL != draw.fBounder && !draw.fBounder->doIRect(finalIRect)) {
821                // nothing to draw
822                return;
823            }
824
825            if (paint.getMaskFilter()->directFilterMaskGPU(fContext, &grPaint,
826                                                           stroke, *devPathPtr)) {
827                // the mask filter was able to draw itself directly, so there's nothing
828                // left to do.
829                return;
830            }
831
832            GrAutoScratchTexture mask;
833
834            if (create_mask_GPU(fContext, maskRect, *devPathPtr, stroke,
835                                grPaint.isAntiAlias(), &mask)) {
836                GrTexture* filtered;
837
838                if (paint.getMaskFilter()->filterMaskGPU(mask.texture(),
839                                                         ctm, maskRect, &filtered, true)) {
840                    // filterMaskGPU gives us ownership of a ref to the result
841                    SkAutoTUnref<GrTexture> atu(filtered);
842
843                    // If the scratch texture that we used as the filter src also holds the filter
844                    // result then we must detach so that this texture isn't recycled for a later
845                    // draw.
846                    if (filtered == mask.texture()) {
847                        mask.detach();
848                        filtered->unref(); // detach transfers GrAutoScratchTexture's ref to us.
849                    }
850
851                    if (draw_mask(fContext, maskRect, &grPaint, filtered)) {
852                        // This path is completely drawn
853                        return;
854                    }
855                }
856            }
857        }
858
859        // draw the mask on the CPU - this is a fallthrough path in case the
860        // GPU path fails
861        SkPaint::Style style = stroke.isHairlineStyle() ? SkPaint::kStroke_Style :
862                                                          SkPaint::kFill_Style;
863        draw_with_mask_filter(fContext, *devPathPtr, paint.getMaskFilter(),
864                              *draw.fClip, draw.fBounder, &grPaint, style);
865        return;
866    }
867
868    fContext->drawPath(grPaint, *pathPtr, stroke);
869}
870
871static const int kBmpSmallTileSize = 1 << 10;
872
873static inline int get_tile_count(const SkIRect& srcRect, int tileSize)  {
874    int tilesX = (srcRect.fRight / tileSize) - (srcRect.fLeft / tileSize) + 1;
875    int tilesY = (srcRect.fBottom / tileSize) - (srcRect.fTop / tileSize) + 1;
876    return tilesX * tilesY;
877}
878
879static int determine_tile_size(const SkBitmap& bitmap, const SkIRect& src, int maxTileSize) {
880    if (maxTileSize <= kBmpSmallTileSize) {
881        return maxTileSize;
882    }
883
884    size_t maxTileTotalTileSize = get_tile_count(src, maxTileSize);
885    size_t smallTotalTileSize = get_tile_count(src, kBmpSmallTileSize);
886
887    maxTileTotalTileSize *= maxTileSize * maxTileSize;
888    smallTotalTileSize *= kBmpSmallTileSize * kBmpSmallTileSize;
889
890    if (maxTileTotalTileSize > 2 * smallTotalTileSize) {
891        return kBmpSmallTileSize;
892    } else {
893        return maxTileSize;
894    }
895}
896
897// Given a bitmap, an optional src rect, and a context with a clip and matrix determine what
898// pixels from the bitmap are necessary.
899static void determine_clipped_src_rect(const GrContext* context,
900                                       const SkBitmap& bitmap,
901                                       const SkRect* srcRectPtr,
902                                       SkIRect* clippedSrcIRect) {
903    const GrClipData* clip = context->getClip();
904    clip->getConservativeBounds(context->getRenderTarget(), clippedSrcIRect, NULL);
905    SkMatrix inv;
906    if (!context->getMatrix().invert(&inv)) {
907        clippedSrcIRect->setEmpty();
908        return;
909    }
910    SkRect clippedSrcRect = SkRect::Make(*clippedSrcIRect);
911    inv.mapRect(&clippedSrcRect);
912    if (NULL != srcRectPtr) {
913        // we've setup src space 0,0 to map to the top left of the src rect.
914        clippedSrcRect.offset(srcRectPtr->fLeft, srcRectPtr->fTop);
915        if (!clippedSrcRect.intersect(*srcRectPtr)) {
916            clippedSrcIRect->setEmpty();
917            return;
918        }
919    }
920    clippedSrcRect.roundOut(clippedSrcIRect);
921    SkIRect bmpBounds = SkIRect::MakeWH(bitmap.width(), bitmap.height());
922    if (!clippedSrcIRect->intersect(bmpBounds)) {
923        clippedSrcIRect->setEmpty();
924    }
925}
926
927bool SkGpuDevice::shouldTileBitmap(const SkBitmap& bitmap,
928                                   const GrTextureParams& params,
929                                   const SkRect* srcRectPtr,
930                                   int maxTileSize,
931                                   int* tileSize,
932                                   SkIRect* clippedSrcRect) const {
933    // if bitmap is explictly texture backed then just use the texture
934    if (NULL != bitmap.getTexture()) {
935        return false;
936    }
937
938    // if it's larger than the max tile size, then we have no choice but tiling.
939    if (bitmap.width() > maxTileSize || bitmap.height() > maxTileSize) {
940        determine_clipped_src_rect(fContext, bitmap, srcRectPtr, clippedSrcRect);
941        *tileSize = determine_tile_size(bitmap, *clippedSrcRect, maxTileSize);
942        return true;
943    }
944
945    if (bitmap.width() * bitmap.height() < 4 * kBmpSmallTileSize * kBmpSmallTileSize) {
946        return false;
947    }
948
949    // if the entire texture is already in our cache then no reason to tile it
950    if (GrIsBitmapInCache(fContext, bitmap, &params)) {
951        return false;
952    }
953
954    // At this point we know we could do the draw by uploading the entire bitmap
955    // as a texture. However, if the texture would be large compared to the
956    // cache size and we don't require most of it for this draw then tile to
957    // reduce the amount of upload and cache spill.
958
959    // assumption here is that sw bitmap size is a good proxy for its size as
960    // a texture
961    size_t bmpSize = bitmap.getSize();
962    size_t cacheSize;
963    fContext->getResourceCacheLimits(NULL, &cacheSize);
964    if (bmpSize < cacheSize / 2) {
965        return false;
966    }
967
968    // Figure out how much of the src we will need based on the src rect and clipping.
969    determine_clipped_src_rect(fContext, bitmap, srcRectPtr, clippedSrcRect);
970    *tileSize = kBmpSmallTileSize; // already know whole bitmap fits in one max sized tile.
971    size_t usedTileBytes = get_tile_count(*clippedSrcRect, kBmpSmallTileSize) *
972                           kBmpSmallTileSize * kBmpSmallTileSize;
973
974    return usedTileBytes < 2 * bmpSize;
975}
976
977void SkGpuDevice::drawBitmap(const SkDraw& origDraw,
978                             const SkBitmap& bitmap,
979                             const SkMatrix& m,
980                             const SkPaint& paint) {
981    SkMatrix concat;
982    SkTCopyOnFirstWrite<SkDraw> draw(origDraw);
983    if (!m.isIdentity()) {
984        concat.setConcat(*draw->fMatrix, m);
985        draw.writable()->fMatrix = &concat;
986    }
987    this->drawBitmapCommon(*draw, bitmap, NULL, NULL, paint, SkCanvas::kNone_DrawBitmapRectFlag);
988}
989
990// This method outsets 'iRect' by 'outset' all around and then clamps its extents to
991// 'clamp'. 'offset' is adjusted to remain positioned over the top-left corner
992// of 'iRect' for all possible outsets/clamps.
993static inline void clamped_outset_with_offset(SkIRect* iRect,
994                                              int outset,
995                                              SkPoint* offset,
996                                              const SkIRect& clamp) {
997    iRect->outset(outset, outset);
998
999    int leftClampDelta = clamp.fLeft - iRect->fLeft;
1000    if (leftClampDelta > 0) {
1001        offset->fX -= outset - leftClampDelta;
1002        iRect->fLeft = clamp.fLeft;
1003    } else {
1004        offset->fX -= outset;
1005    }
1006
1007    int topClampDelta = clamp.fTop - iRect->fTop;
1008    if (topClampDelta > 0) {
1009        offset->fY -= outset - topClampDelta;
1010        iRect->fTop = clamp.fTop;
1011    } else {
1012        offset->fY -= outset;
1013    }
1014
1015    if (iRect->fRight > clamp.fRight) {
1016        iRect->fRight = clamp.fRight;
1017    }
1018    if (iRect->fBottom > clamp.fBottom) {
1019        iRect->fBottom = clamp.fBottom;
1020    }
1021}
1022
1023static bool has_aligned_samples(const SkRect& srcRect,
1024                                const SkRect& transformedRect) {
1025    // detect pixel disalignment
1026    if (SkScalarAbs(SkScalarRoundToScalar(transformedRect.left()) -
1027            transformedRect.left()) < COLOR_BLEED_TOLERANCE &&
1028        SkScalarAbs(SkScalarRoundToScalar(transformedRect.top()) -
1029            transformedRect.top()) < COLOR_BLEED_TOLERANCE &&
1030        SkScalarAbs(transformedRect.width() - srcRect.width()) <
1031            COLOR_BLEED_TOLERANCE &&
1032        SkScalarAbs(transformedRect.height() - srcRect.height()) <
1033            COLOR_BLEED_TOLERANCE) {
1034        return true;
1035    }
1036    return false;
1037}
1038
1039static bool may_color_bleed(const SkRect& srcRect,
1040                            const SkRect& transformedRect,
1041                            const SkMatrix& m) {
1042    // Only gets called if has_aligned_samples returned false.
1043    // So we can assume that sampling is axis aligned but not texel aligned.
1044    SkASSERT(!has_aligned_samples(srcRect, transformedRect));
1045    SkRect innerSrcRect(srcRect), innerTransformedRect,
1046        outerTransformedRect(transformedRect);
1047    innerSrcRect.inset(SK_ScalarHalf, SK_ScalarHalf);
1048    m.mapRect(&innerTransformedRect, innerSrcRect);
1049
1050    // The gap between outerTransformedRect and innerTransformedRect
1051    // represents the projection of the source border area, which is
1052    // problematic for color bleeding.  We must check whether any
1053    // destination pixels sample the border area.
1054    outerTransformedRect.inset(COLOR_BLEED_TOLERANCE, COLOR_BLEED_TOLERANCE);
1055    innerTransformedRect.outset(COLOR_BLEED_TOLERANCE, COLOR_BLEED_TOLERANCE);
1056    SkIRect outer, inner;
1057    outerTransformedRect.round(&outer);
1058    innerTransformedRect.round(&inner);
1059    // If the inner and outer rects round to the same result, it means the
1060    // border does not overlap any pixel centers. Yay!
1061    return inner != outer;
1062}
1063
1064static bool needs_texture_domain(const SkBitmap& bitmap,
1065                                 const SkRect& srcRect,
1066                                 GrTextureParams &params,
1067                                 const SkMatrix& contextMatrix,
1068                                 bool bicubic) {
1069    bool needsTextureDomain = false;
1070
1071    if (bicubic || params.filterMode() != GrTextureParams::kNone_FilterMode) {
1072        // Need texture domain if drawing a sub rect
1073        needsTextureDomain = srcRect.width() < bitmap.width() ||
1074                             srcRect.height() < bitmap.height();
1075        if (!bicubic && needsTextureDomain && contextMatrix.rectStaysRect()) {
1076            // sampling is axis-aligned
1077            SkRect transformedRect;
1078            contextMatrix.mapRect(&transformedRect, srcRect);
1079
1080            if (has_aligned_samples(srcRect, transformedRect)) {
1081                params.setFilterMode(GrTextureParams::kNone_FilterMode);
1082                needsTextureDomain = false;
1083            } else {
1084                needsTextureDomain = may_color_bleed(srcRect, transformedRect, contextMatrix);
1085            }
1086        }
1087    }
1088    return needsTextureDomain;
1089}
1090
1091void SkGpuDevice::drawBitmapCommon(const SkDraw& draw,
1092                                   const SkBitmap& bitmap,
1093                                   const SkRect* srcRectPtr,
1094                                   const SkSize* dstSizePtr,
1095                                   const SkPaint& paint,
1096                                   SkCanvas::DrawBitmapRectFlags flags) {
1097    CHECK_SHOULD_DRAW(draw, false);
1098
1099    SkRect srcRect;
1100    SkSize dstSize;
1101    // If there is no src rect, or the src rect contains the entire bitmap then we're effectively
1102    // in the (easier) bleed case, so update flags.
1103    if (NULL == srcRectPtr) {
1104        SkScalar w = SkIntToScalar(bitmap.width());
1105        SkScalar h = SkIntToScalar(bitmap.height());
1106        dstSize.fWidth = w;
1107        dstSize.fHeight = h;
1108        srcRect.set(0, 0, w, h);
1109        flags = (SkCanvas::DrawBitmapRectFlags) (flags | SkCanvas::kBleed_DrawBitmapRectFlag);
1110    } else {
1111        SkASSERT(NULL != dstSizePtr);
1112        srcRect = *srcRectPtr;
1113        dstSize = *dstSizePtr;
1114        if (srcRect.fLeft <= 0 && srcRect.fTop <= 0 &&
1115            srcRect.fRight >= bitmap.width() && srcRect.fBottom >= bitmap.height()) {
1116            flags = (SkCanvas::DrawBitmapRectFlags) (flags | SkCanvas::kBleed_DrawBitmapRectFlag);
1117        }
1118    }
1119
1120    if (paint.getMaskFilter()){
1121        // Convert the bitmap to a shader so that the rect can be drawn
1122        // through drawRect, which supports mask filters.
1123        SkBitmap        tmp;    // subset of bitmap, if necessary
1124        const SkBitmap* bitmapPtr = &bitmap;
1125        SkMatrix localM;
1126        if (NULL != srcRectPtr) {
1127            localM.setTranslate(-srcRectPtr->fLeft, -srcRectPtr->fTop);
1128            localM.postScale(dstSize.fWidth / srcRectPtr->width(),
1129                             dstSize.fHeight / srcRectPtr->height());
1130            // In bleed mode we position and trim the bitmap based on the src rect which is
1131            // already accounted for in 'm' and 'srcRect'. In clamp mode we need to chop out
1132            // the desired portion of the bitmap and then update 'm' and 'srcRect' to
1133            // compensate.
1134            if (!(SkCanvas::kBleed_DrawBitmapRectFlag & flags)) {
1135                SkIRect iSrc;
1136                srcRect.roundOut(&iSrc);
1137
1138                SkPoint offset = SkPoint::Make(SkIntToScalar(iSrc.fLeft),
1139                                               SkIntToScalar(iSrc.fTop));
1140
1141                if (!bitmap.extractSubset(&tmp, iSrc)) {
1142                    return;     // extraction failed
1143                }
1144                bitmapPtr = &tmp;
1145                srcRect.offset(-offset.fX, -offset.fY);
1146
1147                // The source rect has changed so update the matrix
1148                localM.preTranslate(offset.fX, offset.fY);
1149            }
1150        } else {
1151            localM.reset();
1152        }
1153
1154        SkPaint paintWithShader(paint);
1155        paintWithShader.setShader(SkShader::CreateBitmapShader(*bitmapPtr,
1156            SkShader::kClamp_TileMode, SkShader::kClamp_TileMode, &localM))->unref();
1157        SkRect dstRect = {0, 0, dstSize.fWidth, dstSize.fHeight};
1158        this->drawRect(draw, dstRect, paintWithShader);
1159
1160        return;
1161    }
1162
1163    // If there is no mask filter than it is OK to handle the src rect -> dst rect scaling using
1164    // the view matrix rather than a local matrix.
1165    SkMatrix m;
1166    m.setScale(dstSize.fWidth / srcRect.width(),
1167               dstSize.fHeight / srcRect.height());
1168    fContext->concatMatrix(m);
1169
1170    GrTextureParams params;
1171    SkPaint::FilterLevel paintFilterLevel = paint.getFilterLevel();
1172    GrTextureParams::FilterMode textureFilterMode;
1173
1174    bool doBicubic = false;
1175
1176    switch(paintFilterLevel) {
1177        case SkPaint::kNone_FilterLevel:
1178            textureFilterMode = GrTextureParams::kNone_FilterMode;
1179            break;
1180        case SkPaint::kLow_FilterLevel:
1181            textureFilterMode = GrTextureParams::kBilerp_FilterMode;
1182            break;
1183        case SkPaint::kMedium_FilterLevel:
1184            if (fContext->getMatrix().getMinScale() < SK_Scalar1) {
1185                textureFilterMode = GrTextureParams::kMipMap_FilterMode;
1186            } else {
1187                // Don't trigger MIP level generation unnecessarily.
1188                textureFilterMode = GrTextureParams::kBilerp_FilterMode;
1189            }
1190            break;
1191        case SkPaint::kHigh_FilterLevel:
1192            // Minification can look bad with the bicubic effect.
1193            doBicubic =
1194                GrBicubicEffect::ShouldUseBicubic(fContext->getMatrix(), &textureFilterMode);
1195            break;
1196        default:
1197            SkErrorInternals::SetError( kInvalidPaint_SkError,
1198                                        "Sorry, I don't understand the filtering "
1199                                        "mode you asked for.  Falling back to "
1200                                        "MIPMaps.");
1201            textureFilterMode = GrTextureParams::kMipMap_FilterMode;
1202            break;
1203    }
1204
1205    int tileFilterPad;
1206    if (doBicubic) {
1207        tileFilterPad = GrBicubicEffect::kFilterTexelPad;
1208    } else if (GrTextureParams::kNone_FilterMode == textureFilterMode) {
1209        tileFilterPad = 0;
1210    } else {
1211        tileFilterPad = 1;
1212    }
1213    params.setFilterMode(textureFilterMode);
1214
1215    int maxTileSize = fContext->getMaxTextureSize() - 2 * tileFilterPad;
1216    int tileSize;
1217
1218    SkIRect clippedSrcRect;
1219    if (this->shouldTileBitmap(bitmap, params, srcRectPtr, maxTileSize, &tileSize,
1220                               &clippedSrcRect)) {
1221        this->drawTiledBitmap(bitmap, srcRect, clippedSrcRect, params, paint, flags, tileSize,
1222                              doBicubic);
1223    } else {
1224        // take the simple case
1225        bool needsTextureDomain = needs_texture_domain(bitmap,
1226                                                       srcRect,
1227                                                       params,
1228                                                       fContext->getMatrix(),
1229                                                       doBicubic);
1230        this->internalDrawBitmap(bitmap,
1231                                 srcRect,
1232                                 params,
1233                                 paint,
1234                                 flags,
1235                                 doBicubic,
1236                                 needsTextureDomain);
1237    }
1238}
1239
1240// Break 'bitmap' into several tiles to draw it since it has already
1241// been determined to be too large to fit in VRAM
1242void SkGpuDevice::drawTiledBitmap(const SkBitmap& bitmap,
1243                                  const SkRect& srcRect,
1244                                  const SkIRect& clippedSrcIRect,
1245                                  const GrTextureParams& params,
1246                                  const SkPaint& paint,
1247                                  SkCanvas::DrawBitmapRectFlags flags,
1248                                  int tileSize,
1249                                  bool bicubic) {
1250    // The following pixel lock is technically redundant, but it is desirable
1251    // to lock outside of the tile loop to prevent redecoding the whole image
1252    // at each tile in cases where 'bitmap' holds an SkDiscardablePixelRef that
1253    // is larger than the limit of the discardable memory pool.
1254    SkAutoLockPixels alp(bitmap);
1255    SkRect clippedSrcRect = SkRect::Make(clippedSrcIRect);
1256
1257    int nx = bitmap.width() / tileSize;
1258    int ny = bitmap.height() / tileSize;
1259    for (int x = 0; x <= nx; x++) {
1260        for (int y = 0; y <= ny; y++) {
1261            SkRect tileR;
1262            tileR.set(SkIntToScalar(x * tileSize),
1263                      SkIntToScalar(y * tileSize),
1264                      SkIntToScalar((x + 1) * tileSize),
1265                      SkIntToScalar((y + 1) * tileSize));
1266
1267            if (!SkRect::Intersects(tileR, clippedSrcRect)) {
1268                continue;
1269            }
1270
1271            if (!tileR.intersect(srcRect)) {
1272                continue;
1273            }
1274
1275            SkBitmap tmpB;
1276            SkIRect iTileR;
1277            tileR.roundOut(&iTileR);
1278            SkPoint offset = SkPoint::Make(SkIntToScalar(iTileR.fLeft),
1279                                           SkIntToScalar(iTileR.fTop));
1280
1281            // Adjust the context matrix to draw at the right x,y in device space
1282            SkMatrix tmpM;
1283            GrContext::AutoMatrix am;
1284            tmpM.setTranslate(offset.fX - srcRect.fLeft, offset.fY - srcRect.fTop);
1285            am.setPreConcat(fContext, tmpM);
1286
1287            if (SkPaint::kNone_FilterLevel != paint.getFilterLevel() || bicubic) {
1288                SkIRect iClampRect;
1289
1290                if (SkCanvas::kBleed_DrawBitmapRectFlag & flags) {
1291                    // In bleed mode we want to always expand the tile on all edges
1292                    // but stay within the bitmap bounds
1293                    iClampRect = SkIRect::MakeWH(bitmap.width(), bitmap.height());
1294                } else {
1295                    // In texture-domain/clamp mode we only want to expand the
1296                    // tile on edges interior to "srcRect" (i.e., we want to
1297                    // not bleed across the original clamped edges)
1298                    srcRect.roundOut(&iClampRect);
1299                }
1300                int outset = bicubic ? GrBicubicEffect::kFilterTexelPad : 1;
1301                clamped_outset_with_offset(&iTileR, outset, &offset, iClampRect);
1302            }
1303
1304            if (bitmap.extractSubset(&tmpB, iTileR)) {
1305                // now offset it to make it "local" to our tmp bitmap
1306                tileR.offset(-offset.fX, -offset.fY);
1307                GrTextureParams paramsTemp = params;
1308                bool needsTextureDomain = needs_texture_domain(bitmap,
1309                                                               srcRect,
1310                                                               paramsTemp,
1311                                                               fContext->getMatrix(),
1312                                                               bicubic);
1313                this->internalDrawBitmap(tmpB,
1314                                         tileR,
1315                                         paramsTemp,
1316                                         paint,
1317                                         flags,
1318                                         bicubic,
1319                                         needsTextureDomain);
1320            }
1321        }
1322    }
1323}
1324
1325
1326/*
1327 *  This is called by drawBitmap(), which has to handle images that may be too
1328 *  large to be represented by a single texture.
1329 *
1330 *  internalDrawBitmap assumes that the specified bitmap will fit in a texture
1331 *  and that non-texture portion of the GrPaint has already been setup.
1332 */
1333void SkGpuDevice::internalDrawBitmap(const SkBitmap& bitmap,
1334                                     const SkRect& srcRect,
1335                                     const GrTextureParams& params,
1336                                     const SkPaint& paint,
1337                                     SkCanvas::DrawBitmapRectFlags flags,
1338                                     bool bicubic,
1339                                     bool needsTextureDomain) {
1340    SkASSERT(bitmap.width() <= fContext->getMaxTextureSize() &&
1341             bitmap.height() <= fContext->getMaxTextureSize());
1342
1343    GrTexture* texture;
1344    SkAutoCachedTexture act(this, bitmap, &params, &texture);
1345    if (NULL == texture) {
1346        return;
1347    }
1348
1349    SkRect dstRect = {0, 0, srcRect.width(), srcRect.height() };
1350    SkRect paintRect;
1351    SkScalar wInv = SkScalarInvert(SkIntToScalar(texture->width()));
1352    SkScalar hInv = SkScalarInvert(SkIntToScalar(texture->height()));
1353    paintRect.setLTRB(SkScalarMul(srcRect.fLeft,   wInv),
1354                      SkScalarMul(srcRect.fTop,    hInv),
1355                      SkScalarMul(srcRect.fRight,  wInv),
1356                      SkScalarMul(srcRect.fBottom, hInv));
1357
1358    SkRect textureDomain = SkRect::MakeEmpty();
1359    SkAutoTUnref<GrEffectRef> effect;
1360    if (needsTextureDomain && !(flags & SkCanvas::kBleed_DrawBitmapRectFlag)) {
1361        // Use a constrained texture domain to avoid color bleeding
1362        SkScalar left, top, right, bottom;
1363        if (srcRect.width() > SK_Scalar1) {
1364            SkScalar border = SK_ScalarHalf / texture->width();
1365            left = paintRect.left() + border;
1366            right = paintRect.right() - border;
1367        } else {
1368            left = right = SkScalarHalf(paintRect.left() + paintRect.right());
1369        }
1370        if (srcRect.height() > SK_Scalar1) {
1371            SkScalar border = SK_ScalarHalf / texture->height();
1372            top = paintRect.top() + border;
1373            bottom = paintRect.bottom() - border;
1374        } else {
1375            top = bottom = SkScalarHalf(paintRect.top() + paintRect.bottom());
1376        }
1377        textureDomain.setLTRB(left, top, right, bottom);
1378        if (bicubic) {
1379            effect.reset(GrBicubicEffect::Create(texture, SkMatrix::I(), textureDomain));
1380        } else {
1381            effect.reset(GrTextureDomainEffect::Create(texture,
1382                                                       SkMatrix::I(),
1383                                                       textureDomain,
1384                                                       GrTextureDomain::kClamp_Mode,
1385                                                       params.filterMode()));
1386        }
1387    } else if (bicubic) {
1388        SkASSERT(GrTextureParams::kNone_FilterMode == params.filterMode());
1389        SkShader::TileMode tileModes[2] = { params.getTileModeX(), params.getTileModeY() };
1390        effect.reset(GrBicubicEffect::Create(texture, SkMatrix::I(), tileModes));
1391    } else {
1392        effect.reset(GrSimpleTextureEffect::Create(texture, SkMatrix::I(), params));
1393    }
1394
1395    // Construct a GrPaint by setting the bitmap texture as the first effect and then configuring
1396    // the rest from the SkPaint.
1397    GrPaint grPaint;
1398    grPaint.addColorEffect(effect);
1399    bool alphaOnly = !(SkBitmap::kA8_Config == bitmap.config());
1400    SkPaint2GrPaintNoShader(this->context(), paint, alphaOnly, false, &grPaint);
1401
1402    fContext->drawRectToRect(grPaint, dstRect, paintRect, NULL);
1403}
1404
1405static bool filter_texture(SkBaseDevice* device, GrContext* context,
1406                           GrTexture* texture, const SkImageFilter* filter,
1407                           int w, int h, const SkImageFilter::Context& ctx,
1408                           SkBitmap* result, SkIPoint* offset) {
1409    SkASSERT(filter);
1410    SkDeviceImageFilterProxy proxy(device);
1411
1412    if (filter->canFilterImageGPU()) {
1413        // Save the render target and set it to NULL, so we don't accidentally draw to it in the
1414        // filter.  Also set the clip wide open and the matrix to identity.
1415        GrContext::AutoWideOpenIdentityDraw awo(context, NULL);
1416        return filter->filterImageGPU(&proxy, wrap_texture(texture), ctx, result, offset);
1417    } else {
1418        return false;
1419    }
1420}
1421
1422void SkGpuDevice::drawSprite(const SkDraw& draw, const SkBitmap& bitmap,
1423                             int left, int top, const SkPaint& paint) {
1424    // drawSprite is defined to be in device coords.
1425    CHECK_SHOULD_DRAW(draw, true);
1426
1427    SkAutoLockPixels alp(bitmap, !bitmap.getTexture());
1428    if (!bitmap.getTexture() && !bitmap.readyToDraw()) {
1429        return;
1430    }
1431
1432    int w = bitmap.width();
1433    int h = bitmap.height();
1434
1435    GrTexture* texture;
1436    // draw sprite uses the default texture params
1437    SkAutoCachedTexture act(this, bitmap, NULL, &texture);
1438
1439    SkImageFilter* filter = paint.getImageFilter();
1440    // This bitmap will own the filtered result as a texture.
1441    SkBitmap filteredBitmap;
1442
1443    if (NULL != filter) {
1444        SkIPoint offset = SkIPoint::Make(0, 0);
1445        SkMatrix matrix(*draw.fMatrix);
1446        matrix.postTranslate(SkIntToScalar(-left), SkIntToScalar(-top));
1447        SkIRect clipBounds = SkIRect::MakeWH(bitmap.width(), bitmap.height());
1448        SkImageFilter::Cache* cache = SkImageFilter::Cache::Create();
1449        SkAutoUnref aur(cache);
1450        SkImageFilter::Context ctx(matrix, clipBounds, cache);
1451        if (filter_texture(this, fContext, texture, filter, w, h, ctx, &filteredBitmap,
1452                           &offset)) {
1453            texture = (GrTexture*) filteredBitmap.getTexture();
1454            w = filteredBitmap.width();
1455            h = filteredBitmap.height();
1456            left += offset.x();
1457            top += offset.y();
1458        } else {
1459            return;
1460        }
1461    }
1462
1463    GrPaint grPaint;
1464    grPaint.addColorTextureEffect(texture, SkMatrix::I());
1465
1466    SkPaint2GrPaintNoShader(this->context(), paint, true, false, &grPaint);
1467
1468    fContext->drawRectToRect(grPaint,
1469                             SkRect::MakeXYWH(SkIntToScalar(left),
1470                                              SkIntToScalar(top),
1471                                              SkIntToScalar(w),
1472                                              SkIntToScalar(h)),
1473                             SkRect::MakeXYWH(0,
1474                                              0,
1475                                              SK_Scalar1 * w / texture->width(),
1476                                              SK_Scalar1 * h / texture->height()));
1477}
1478
1479void SkGpuDevice::drawBitmapRect(const SkDraw& origDraw, const SkBitmap& bitmap,
1480                                 const SkRect* src, const SkRect& dst,
1481                                 const SkPaint& paint,
1482                                 SkCanvas::DrawBitmapRectFlags flags) {
1483    SkMatrix    matrix;
1484    SkRect      bitmapBounds, tmpSrc;
1485
1486    bitmapBounds.set(0, 0,
1487                     SkIntToScalar(bitmap.width()),
1488                     SkIntToScalar(bitmap.height()));
1489
1490    // Compute matrix from the two rectangles
1491    if (NULL != src) {
1492        tmpSrc = *src;
1493    } else {
1494        tmpSrc = bitmapBounds;
1495    }
1496
1497    matrix.setRectToRect(tmpSrc, dst, SkMatrix::kFill_ScaleToFit);
1498
1499    // clip the tmpSrc to the bounds of the bitmap. No check needed if src==null.
1500    if (NULL != src) {
1501        if (!bitmapBounds.contains(tmpSrc)) {
1502            if (!tmpSrc.intersect(bitmapBounds)) {
1503                return; // nothing to draw
1504            }
1505        }
1506    }
1507
1508    SkRect tmpDst;
1509    matrix.mapRect(&tmpDst, tmpSrc);
1510
1511    SkTCopyOnFirstWrite<SkDraw> draw(origDraw);
1512    if (0 != tmpDst.fLeft || 0 != tmpDst.fTop) {
1513        // Translate so that tempDst's top left is at the origin.
1514        matrix = *origDraw.fMatrix;
1515        matrix.preTranslate(tmpDst.fLeft, tmpDst.fTop);
1516        draw.writable()->fMatrix = &matrix;
1517    }
1518    SkSize dstSize;
1519    dstSize.fWidth = tmpDst.width();
1520    dstSize.fHeight = tmpDst.height();
1521
1522    this->drawBitmapCommon(*draw, bitmap, &tmpSrc, &dstSize, paint, flags);
1523}
1524
1525void SkGpuDevice::drawDevice(const SkDraw& draw, SkBaseDevice* device,
1526                             int x, int y, const SkPaint& paint) {
1527    // clear of the source device must occur before CHECK_SHOULD_DRAW
1528    SkGpuDevice* dev = static_cast<SkGpuDevice*>(device);
1529    if (dev->fNeedClear) {
1530        // TODO: could check here whether we really need to draw at all
1531        dev->clear(0x0);
1532    }
1533
1534    // drawDevice is defined to be in device coords.
1535    CHECK_SHOULD_DRAW(draw, true);
1536
1537    GrRenderTarget* devRT = dev->accessRenderTarget();
1538    GrTexture* devTex;
1539    if (NULL == (devTex = devRT->asTexture())) {
1540        return;
1541    }
1542
1543    const SkBitmap& bm = dev->accessBitmap(false);
1544    int w = bm.width();
1545    int h = bm.height();
1546
1547    SkImageFilter* filter = paint.getImageFilter();
1548    // This bitmap will own the filtered result as a texture.
1549    SkBitmap filteredBitmap;
1550
1551    if (NULL != filter) {
1552        SkIPoint offset = SkIPoint::Make(0, 0);
1553        SkMatrix matrix(*draw.fMatrix);
1554        matrix.postTranslate(SkIntToScalar(-x), SkIntToScalar(-y));
1555        SkIRect clipBounds = SkIRect::MakeWH(devTex->width(), devTex->height());
1556        SkImageFilter::Cache* cache = SkImageFilter::Cache::Create();
1557        SkAutoUnref aur(cache);
1558        SkImageFilter::Context ctx(matrix, clipBounds, cache);
1559        if (filter_texture(this, fContext, devTex, filter, w, h, ctx, &filteredBitmap,
1560                           &offset)) {
1561            devTex = filteredBitmap.getTexture();
1562            w = filteredBitmap.width();
1563            h = filteredBitmap.height();
1564            x += offset.fX;
1565            y += offset.fY;
1566        } else {
1567            return;
1568        }
1569    }
1570
1571    GrPaint grPaint;
1572    grPaint.addColorTextureEffect(devTex, SkMatrix::I());
1573
1574    SkPaint2GrPaintNoShader(this->context(), paint, true, false, &grPaint);
1575
1576    SkRect dstRect = SkRect::MakeXYWH(SkIntToScalar(x),
1577                                      SkIntToScalar(y),
1578                                      SkIntToScalar(w),
1579                                      SkIntToScalar(h));
1580
1581    // The device being drawn may not fill up its texture (e.g. saveLayer uses approximate
1582    // scratch texture).
1583    SkRect srcRect = SkRect::MakeWH(SK_Scalar1 * w / devTex->width(),
1584                                    SK_Scalar1 * h / devTex->height());
1585
1586    fContext->drawRectToRect(grPaint, dstRect, srcRect);
1587}
1588
1589bool SkGpuDevice::canHandleImageFilter(const SkImageFilter* filter) {
1590    return filter->canFilterImageGPU();
1591}
1592
1593bool SkGpuDevice::filterImage(const SkImageFilter* filter, const SkBitmap& src,
1594                              const SkImageFilter::Context& ctx,
1595                              SkBitmap* result, SkIPoint* offset) {
1596    // want explicitly our impl, so guard against a subclass of us overriding it
1597    if (!this->SkGpuDevice::canHandleImageFilter(filter)) {
1598        return false;
1599    }
1600
1601    SkAutoLockPixels alp(src, !src.getTexture());
1602    if (!src.getTexture() && !src.readyToDraw()) {
1603        return false;
1604    }
1605
1606    GrTexture* texture;
1607    // We assume here that the filter will not attempt to tile the src. Otherwise, this cache lookup
1608    // must be pushed upstack.
1609    SkAutoCachedTexture act(this, src, NULL, &texture);
1610
1611    return filter_texture(this, fContext, texture, filter, src.width(), src.height(), ctx,
1612                          result, offset);
1613}
1614
1615///////////////////////////////////////////////////////////////////////////////
1616
1617// must be in SkCanvas::VertexMode order
1618static const GrPrimitiveType gVertexMode2PrimitiveType[] = {
1619    kTriangles_GrPrimitiveType,
1620    kTriangleStrip_GrPrimitiveType,
1621    kTriangleFan_GrPrimitiveType,
1622};
1623
1624void SkGpuDevice::drawVertices(const SkDraw& draw, SkCanvas::VertexMode vmode,
1625                              int vertexCount, const SkPoint vertices[],
1626                              const SkPoint texs[], const SkColor colors[],
1627                              SkXfermode* xmode,
1628                              const uint16_t indices[], int indexCount,
1629                              const SkPaint& paint) {
1630    CHECK_SHOULD_DRAW(draw, false);
1631
1632    // If both textures and vertex-colors are NULL, strokes hairlines with the paint's color.
1633    if ((NULL == texs || NULL == paint.getShader()) && NULL == colors) {
1634        texs = NULL;
1635        SkPaint copy(paint);
1636        copy.setStyle(SkPaint::kStroke_Style);
1637        copy.setStrokeWidth(0);
1638
1639        VertState       state(vertexCount, indices, indexCount);
1640        VertState::Proc vertProc = state.chooseProc(vmode);
1641
1642        SkPoint* pts = new SkPoint[vertexCount * 6];
1643        int i = 0;
1644        while (vertProc(&state)) {
1645            pts[i] = vertices[state.f0];
1646            pts[i + 1] = vertices[state.f1];
1647            pts[i + 2] = vertices[state.f1];
1648            pts[i + 3] = vertices[state.f2];
1649            pts[i + 4] = vertices[state.f2];
1650            pts[i + 5] = vertices[state.f0];
1651            i += 6;
1652        }
1653        draw.drawPoints(SkCanvas::kLines_PointMode, i, pts, copy, true);
1654        return;
1655    }
1656
1657    GrPaint grPaint;
1658    // we ignore the shader if texs is null.
1659    if (NULL == texs) {
1660        SkPaint2GrPaintNoShader(this->context(), paint, false, NULL == colors, &grPaint);
1661    } else {
1662        SkPaint2GrPaintShader(this->context(), paint, NULL == colors, &grPaint);
1663    }
1664
1665    if (NULL != xmode && NULL != texs && NULL != colors) {
1666        if (!SkXfermode::IsMode(xmode, SkXfermode::kModulate_Mode)) {
1667            SkDebugf("Unsupported vertex-color/texture xfer mode.\n");
1668#if 0
1669            return
1670#endif
1671        }
1672    }
1673
1674    SkAutoSTMalloc<128, GrColor> convertedColors(0);
1675    if (NULL != colors) {
1676        // need to convert byte order and from non-PM to PM
1677        convertedColors.reset(vertexCount);
1678        SkColor color;
1679        for (int i = 0; i < vertexCount; ++i) {
1680            color = colors[i];
1681            if (paint.getAlpha() != 255) {
1682                color = SkColorSetA(color, SkMulDiv255Round(SkColorGetA(color), paint.getAlpha()));
1683            }
1684            convertedColors[i] = SkColor2GrColor(color);
1685        }
1686        colors = convertedColors.get();
1687    }
1688    fContext->drawVertices(grPaint,
1689                           gVertexMode2PrimitiveType[vmode],
1690                           vertexCount,
1691                           vertices,
1692                           texs,
1693                           colors,
1694                           indices,
1695                           indexCount);
1696}
1697
1698///////////////////////////////////////////////////////////////////////////////
1699
1700void SkGpuDevice::drawText(const SkDraw& draw, const void* text,
1701                          size_t byteLength, SkScalar x, SkScalar y,
1702                          const SkPaint& paint) {
1703    CHECK_SHOULD_DRAW(draw, false);
1704
1705    if (fMainTextContext->canDraw(paint)) {
1706        GrPaint grPaint;
1707        SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
1708
1709        SkDEBUGCODE(this->validate();)
1710
1711        fMainTextContext->drawText(grPaint, paint, (const char *)text, byteLength, x, y);
1712    } else if (fFallbackTextContext && fFallbackTextContext->canDraw(paint)) {
1713        GrPaint grPaint;
1714        SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
1715
1716        SkDEBUGCODE(this->validate();)
1717
1718        fFallbackTextContext->drawText(grPaint, paint, (const char *)text, byteLength, x, y);
1719    } else {
1720        // this guy will just call our drawPath()
1721        draw.drawText_asPaths((const char*)text, byteLength, x, y, paint);
1722    }
1723}
1724
1725void SkGpuDevice::drawPosText(const SkDraw& draw, const void* text,
1726                             size_t byteLength, const SkScalar pos[],
1727                             SkScalar constY, int scalarsPerPos,
1728                             const SkPaint& paint) {
1729    CHECK_SHOULD_DRAW(draw, false);
1730
1731    if (fMainTextContext->canDraw(paint)) {
1732        GrPaint grPaint;
1733        SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
1734
1735        SkDEBUGCODE(this->validate();)
1736
1737        fMainTextContext->drawPosText(grPaint, paint, (const char *)text, byteLength, pos,
1738                                      constY, scalarsPerPos);
1739    } else if (fFallbackTextContext && fFallbackTextContext->canDraw(paint)) {
1740        GrPaint grPaint;
1741        SkPaint2GrPaintShader(this->context(), paint, true, &grPaint);
1742
1743        SkDEBUGCODE(this->validate();)
1744
1745        fFallbackTextContext->drawPosText(grPaint, paint, (const char *)text, byteLength, pos,
1746                                          constY, scalarsPerPos);
1747    } else {
1748        draw.drawPosText_asPaths((const char*)text, byteLength, pos, constY,
1749                                 scalarsPerPos, paint);
1750    }
1751}
1752
1753void SkGpuDevice::drawTextOnPath(const SkDraw& draw, const void* text,
1754                                size_t len, const SkPath& path,
1755                                const SkMatrix* m, const SkPaint& paint) {
1756    CHECK_SHOULD_DRAW(draw, false);
1757
1758    SkASSERT(draw.fDevice == this);
1759    draw.drawTextOnPath((const char*)text, len, path, m, paint);
1760}
1761
1762///////////////////////////////////////////////////////////////////////////////
1763
1764bool SkGpuDevice::filterTextFlags(const SkPaint& paint, TextFlags* flags) {
1765    if (!paint.isLCDRenderText()) {
1766        // we're cool with the paint as is
1767        return false;
1768    }
1769
1770    if (paint.getShader() ||
1771        paint.getXfermode() || // unless its srcover
1772        paint.getMaskFilter() ||
1773        paint.getRasterizer() ||
1774        paint.getColorFilter() ||
1775        paint.getPathEffect() ||
1776        paint.isFakeBoldText() ||
1777        paint.getStyle() != SkPaint::kFill_Style) {
1778        // turn off lcd
1779        flags->fFlags = paint.getFlags() & ~SkPaint::kLCDRenderText_Flag;
1780        flags->fHinting = paint.getHinting();
1781        return true;
1782    }
1783    // we're cool with the paint as is
1784    return false;
1785}
1786
1787void SkGpuDevice::flush() {
1788    DO_DEFERRED_CLEAR();
1789    fContext->resolveRenderTarget(fRenderTarget);
1790}
1791
1792///////////////////////////////////////////////////////////////////////////////
1793
1794SkBaseDevice* SkGpuDevice::onCreateDevice(const SkImageInfo& info, Usage usage) {
1795    GrTextureDesc desc;
1796    desc.fConfig = fRenderTarget->config();
1797    desc.fFlags = kRenderTarget_GrTextureFlagBit;
1798    desc.fWidth = info.width();
1799    desc.fHeight = info.height();
1800    desc.fSampleCnt = fRenderTarget->numSamples();
1801
1802    SkAutoTUnref<GrTexture> texture;
1803    // Skia's convention is to only clear a device if it is non-opaque.
1804    unsigned flags = info.isOpaque() ? 0 : kNeedClear_Flag;
1805
1806#if CACHE_COMPATIBLE_DEVICE_TEXTURES
1807    // layers are never draw in repeat modes, so we can request an approx
1808    // match and ignore any padding.
1809    flags |= kCached_Flag;
1810    const GrContext::ScratchTexMatch match = (kSaveLayer_Usage == usage) ?
1811                                                GrContext::kApprox_ScratchTexMatch :
1812                                                GrContext::kExact_ScratchTexMatch;
1813    texture.reset(fContext->lockAndRefScratchTexture(desc, match));
1814#else
1815    texture.reset(fContext->createUncachedTexture(desc, NULL, 0));
1816#endif
1817    if (NULL != texture.get()) {
1818        return SkGpuDevice::Create(texture, flags);
1819    } else {
1820        GrPrintf("---- failed to create compatible device texture [%d %d]\n",
1821                 info.width(), info.height());
1822        return NULL;
1823    }
1824}
1825
1826SkSurface* SkGpuDevice::newSurface(const SkImageInfo& info) {
1827    return SkSurface::NewRenderTarget(fContext, info, fRenderTarget->numSamples());
1828}
1829
1830void SkGpuDevice::EXPERIMENTAL_optimize(SkPicture* picture) {
1831    SkPicture::AccelData::Key key = GPUAccelData::ComputeAccelDataKey();
1832
1833    const SkPicture::AccelData* existing = picture->EXPERIMENTAL_getAccelData(key);
1834    if (NULL != existing) {
1835        return;
1836    }
1837
1838    SkAutoTUnref<GPUAccelData> data(SkNEW_ARGS(GPUAccelData, (key)));
1839
1840    picture->EXPERIMENTAL_addAccelData(data);
1841
1842    GatherGPUInfo(picture, data);
1843}
1844
1845static void wrap_texture(GrTexture* texture, int width, int height, SkBitmap* result) {
1846    SkImageInfo info = SkImageInfo::MakeN32Premul(width, height);
1847    result->setInfo(info);
1848    result->setPixelRef(SkNEW_ARGS(SkGrPixelRef, (info, texture)))->unref();
1849}
1850
1851void SkGpuDevice::EXPERIMENTAL_purge(SkPicture* picture) {
1852
1853}
1854
1855bool SkGpuDevice::EXPERIMENTAL_drawPicture(SkCanvas* canvas, SkPicture* picture) {
1856
1857    SkPicture::AccelData::Key key = GPUAccelData::ComputeAccelDataKey();
1858
1859    const SkPicture::AccelData* data = picture->EXPERIMENTAL_getAccelData(key);
1860    if (NULL == data) {
1861        return false;
1862    }
1863
1864    const GPUAccelData *gpuData = static_cast<const GPUAccelData*>(data);
1865
1866    if (0 == gpuData->numSaveLayers()) {
1867        return false;
1868    }
1869
1870    SkAutoTArray<bool> pullForward(gpuData->numSaveLayers());
1871    for (int i = 0; i < gpuData->numSaveLayers(); ++i) {
1872        pullForward[i] = false;
1873    }
1874
1875    SkRect clipBounds;
1876    if (!canvas->getClipBounds(&clipBounds)) {
1877        return true;
1878    }
1879    SkIRect query;
1880    clipBounds.roundOut(&query);
1881
1882    const SkPicture::OperationList& ops = picture->EXPERIMENTAL_getActiveOps(query);
1883
1884    // This code pre-renders the entire layer since it will be cached and potentially
1885    // reused with different clips (e.g., in different tiles). Because of this the
1886    // clip will not be limiting the size of the pre-rendered layer. kSaveLayerMaxSize
1887    // is used to limit which clips are pre-rendered.
1888    static const int kSaveLayerMaxSize = 256;
1889
1890    if (ops.valid()) {
1891        // In this case the picture has been generated with a BBH so we use
1892        // the BBH to limit the pre-rendering to just the layers needed to cover
1893        // the region being drawn
1894        for (int i = 0; i < ops.numOps(); ++i) {
1895            uint32_t offset = ops.offset(i);
1896
1897            // For now we're saving all the layers in the GPUAccelData so they
1898            // can be nested. Additionally, the nested layers appear before
1899            // their parent in the list.
1900            for (int j = 0 ; j < gpuData->numSaveLayers(); ++j) {
1901                const GPUAccelData::SaveLayerInfo& info = gpuData->saveLayerInfo(j);
1902
1903                if (pullForward[j]) {
1904                    continue;            // already pulling forward
1905                }
1906
1907                if (offset < info.fSaveLayerOpID || offset > info.fRestoreOpID) {
1908                    continue;            // the op isn't in this range
1909                }
1910
1911                // TODO: once this code is more stable unsuitable layers can
1912                // just be omitted during the optimization stage
1913                if (!info.fValid ||
1914                    kSaveLayerMaxSize < info.fSize.fWidth ||
1915                    kSaveLayerMaxSize < info.fSize.fHeight ||
1916                    info.fIsNested) {
1917                    continue;            // this layer is unsuitable
1918                }
1919
1920                pullForward[j] = true;
1921            }
1922        }
1923    } else {
1924        // In this case there is no BBH associated with the picture. Pre-render
1925        // all the layers that intersect the drawn region
1926        for (int j = 0; j < gpuData->numSaveLayers(); ++j) {
1927            const GPUAccelData::SaveLayerInfo& info = gpuData->saveLayerInfo(j);
1928
1929            SkIRect layerRect = SkIRect::MakeXYWH(info.fOffset.fX,
1930                                                  info.fOffset.fY,
1931                                                  info.fSize.fWidth,
1932                                                  info.fSize.fHeight);
1933
1934            if (!SkIRect::Intersects(query, layerRect)) {
1935                continue;
1936            }
1937
1938            // TODO: once this code is more stable unsuitable layers can
1939            // just be omitted during the optimization stage
1940            if (!info.fValid ||
1941                kSaveLayerMaxSize < info.fSize.fWidth ||
1942                kSaveLayerMaxSize < info.fSize.fHeight ||
1943                info.fIsNested) {
1944                continue;
1945            }
1946
1947            pullForward[j] = true;
1948        }
1949    }
1950
1951    SkPicturePlayback::PlaybackReplacements replacements;
1952
1953    for (int i = 0; i < gpuData->numSaveLayers(); ++i) {
1954        if (pullForward[i]) {
1955            GrCachedLayer* layer = fContext->getLayerCache()->findLayerOrCreate(picture, i);
1956
1957            const GPUAccelData::SaveLayerInfo& info = gpuData->saveLayerInfo(i);
1958
1959            if (NULL != picture->fPlayback) {
1960                SkPicturePlayback::PlaybackReplacements::ReplacementInfo* layerInfo =
1961                                                                        replacements.push();
1962                layerInfo->fStart = info.fSaveLayerOpID;
1963                layerInfo->fStop = info.fRestoreOpID;
1964                layerInfo->fPos = info.fOffset;
1965
1966                GrTextureDesc desc;
1967                desc.fFlags = kRenderTarget_GrTextureFlagBit;
1968                desc.fWidth = info.fSize.fWidth;
1969                desc.fHeight = info.fSize.fHeight;
1970                desc.fConfig = kSkia8888_GrPixelConfig;
1971                // TODO: need to deal with sample count
1972
1973                bool bNeedsRendering = true;
1974
1975                // This just uses scratch textures and doesn't cache the texture.
1976                // This can yield a lot of re-rendering
1977                if (NULL == layer->getTexture()) {
1978                    layer->setTexture(fContext->lockAndRefScratchTexture(desc,
1979                                                        GrContext::kApprox_ScratchTexMatch));
1980                    if (NULL == layer->getTexture()) {
1981                        continue;
1982                    }
1983                } else {
1984                    bNeedsRendering = false;
1985                }
1986
1987                layerInfo->fBM = SkNEW(SkBitmap);
1988                wrap_texture(layer->getTexture(), desc.fWidth, desc.fHeight, layerInfo->fBM);
1989
1990                SkASSERT(info.fPaint);
1991                layerInfo->fPaint = info.fPaint;
1992
1993                if (bNeedsRendering) {
1994                    SkAutoTUnref<SkSurface> surface(SkSurface::NewRenderTargetDirect(
1995                                                        layer->getTexture()->asRenderTarget()));
1996
1997                    SkCanvas* canvas = surface->getCanvas();
1998
1999                    canvas->setMatrix(info.fCTM);
2000                    canvas->clear(SK_ColorTRANSPARENT);
2001
2002                    picture->fPlayback->setDrawLimits(info.fSaveLayerOpID, info.fRestoreOpID);
2003                    picture->fPlayback->draw(*canvas, NULL);
2004                    picture->fPlayback->setDrawLimits(0, 0);
2005                    canvas->flush();
2006                }
2007            }
2008        }
2009    }
2010
2011    // Playback using new layers
2012    picture->fPlayback->setReplacements(&replacements);
2013    picture->fPlayback->draw(*canvas, NULL);
2014    picture->fPlayback->setReplacements(NULL);
2015
2016    for (int i = 0; i < gpuData->numSaveLayers(); ++i) {
2017        GrCachedLayer* layer = fContext->getLayerCache()->findLayerOrCreate(picture, i);
2018
2019        if (NULL != layer->getTexture()) {
2020            fContext->unlockScratchTexture(layer->getTexture());
2021            layer->setTexture(NULL);
2022        }
2023    }
2024
2025    return true;
2026}
2027