1/*
2 * Copyright 2012 The Android Open Source Project
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 "SkMatrixConvolutionImageFilter.h"
9#include "SkBitmap.h"
10#include "SkColorPriv.h"
11#include "SkFlattenableBuffers.h"
12#include "SkRect.h"
13#include "SkUnPreMultiply.h"
14
15#if SK_SUPPORT_GPU
16#include "gl/GrGLEffect.h"
17#include "effects/GrSingleTextureEffect.h"
18#include "GrTBackendEffectFactory.h"
19#include "GrTexture.h"
20#include "SkMatrix.h"
21#endif
22
23static bool tile_mode_is_valid(SkMatrixConvolutionImageFilter::TileMode tileMode) {
24    switch (tileMode) {
25    case SkMatrixConvolutionImageFilter::kClamp_TileMode:
26    case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
27    case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
28        return true;
29    default:
30        break;
31    }
32    return false;
33}
34
35SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(
36    const SkISize& kernelSize,
37    const SkScalar* kernel,
38    SkScalar gain,
39    SkScalar bias,
40    const SkIPoint& target,
41    TileMode tileMode,
42    bool convolveAlpha,
43    SkImageFilter* input,
44    const CropRect* cropRect)
45  : INHERITED(input, cropRect),
46    fKernelSize(kernelSize),
47    fGain(gain),
48    fBias(bias),
49    fTarget(target),
50    fTileMode(tileMode),
51    fConvolveAlpha(convolveAlpha) {
52    uint32_t size = fKernelSize.fWidth * fKernelSize.fHeight;
53    fKernel = SkNEW_ARRAY(SkScalar, size);
54    memcpy(fKernel, kernel, size * sizeof(SkScalar));
55    SkASSERT(kernelSize.fWidth >= 1 && kernelSize.fHeight >= 1);
56    SkASSERT(target.fX >= 0 && target.fX < kernelSize.fWidth);
57    SkASSERT(target.fY >= 0 && target.fY < kernelSize.fHeight);
58}
59
60SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(SkFlattenableReadBuffer& buffer)
61    : INHERITED(1, buffer) {
62    // We need to be able to read at most SK_MaxS32 bytes, so divide that
63    // by the size of a scalar to know how many scalars we can read.
64    static const int32_t kMaxSize = SK_MaxS32 / sizeof(SkScalar);
65    fKernelSize.fWidth = buffer.readInt();
66    fKernelSize.fHeight = buffer.readInt();
67    if ((fKernelSize.fWidth >= 1) && (fKernelSize.fHeight >= 1) &&
68        // Make sure size won't be larger than a signed int,
69        // which would still be extremely large for a kernel,
70        // but we don't impose a hard limit for kernel size
71        (kMaxSize / fKernelSize.fWidth >= fKernelSize.fHeight)) {
72        size_t size = fKernelSize.fWidth * fKernelSize.fHeight;
73        fKernel = SkNEW_ARRAY(SkScalar, size);
74        SkDEBUGCODE(bool success =) buffer.readScalarArray(fKernel, size);
75        SkASSERT(success);
76    } else {
77        fKernel = 0;
78    }
79    fGain = buffer.readScalar();
80    fBias = buffer.readScalar();
81    fTarget.fX = buffer.readInt();
82    fTarget.fY = buffer.readInt();
83    fTileMode = (TileMode) buffer.readInt();
84    fConvolveAlpha = buffer.readBool();
85    buffer.validate((fKernel != 0) &&
86                    SkScalarIsFinite(fGain) &&
87                    SkScalarIsFinite(fBias) &&
88                    tile_mode_is_valid(fTileMode));
89}
90
91void SkMatrixConvolutionImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
92    this->INHERITED::flatten(buffer);
93    buffer.writeInt(fKernelSize.fWidth);
94    buffer.writeInt(fKernelSize.fHeight);
95    buffer.writeScalarArray(fKernel, fKernelSize.fWidth * fKernelSize.fHeight);
96    buffer.writeScalar(fGain);
97    buffer.writeScalar(fBias);
98    buffer.writeInt(fTarget.fX);
99    buffer.writeInt(fTarget.fY);
100    buffer.writeInt((int) fTileMode);
101    buffer.writeBool(fConvolveAlpha);
102}
103
104SkMatrixConvolutionImageFilter::~SkMatrixConvolutionImageFilter() {
105    delete[] fKernel;
106}
107
108class UncheckedPixelFetcher {
109public:
110    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
111        return *src.getAddr32(x, y);
112    }
113};
114
115class ClampPixelFetcher {
116public:
117    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
118        x = SkPin32(x, bounds.fLeft, bounds.fRight - 1);
119        y = SkPin32(y, bounds.fTop, bounds.fBottom - 1);
120        return *src.getAddr32(x, y);
121    }
122};
123
124class RepeatPixelFetcher {
125public:
126    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
127        x = (x - bounds.left()) % bounds.width() + bounds.left();
128        y = (y - bounds.top()) % bounds.height() + bounds.top();
129        if (x < bounds.left()) {
130            x += bounds.width();
131        }
132        if (y < bounds.top()) {
133            y += bounds.height();
134        }
135        return *src.getAddr32(x, y);
136    }
137};
138
139class ClampToBlackPixelFetcher {
140public:
141    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
142        if (x < bounds.fLeft || x >= bounds.fRight || y < bounds.fTop || y >= bounds.fBottom) {
143            return 0;
144        } else {
145            return *src.getAddr32(x, y);
146        }
147    }
148};
149
150template<class PixelFetcher, bool convolveAlpha>
151void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src,
152                                                  SkBitmap* result,
153                                                  const SkIRect& rect,
154                                                  const SkIRect& bounds) {
155    for (int y = rect.fTop; y < rect.fBottom; ++y) {
156        SkPMColor* dptr = result->getAddr32(rect.fLeft - bounds.fLeft, y - bounds.fTop);
157        for (int x = rect.fLeft; x < rect.fRight; ++x) {
158            SkScalar sumA = 0, sumR = 0, sumG = 0, sumB = 0;
159            for (int cy = 0; cy < fKernelSize.fHeight; cy++) {
160                for (int cx = 0; cx < fKernelSize.fWidth; cx++) {
161                    SkPMColor s = PixelFetcher::fetch(src,
162                                                      x + cx - fTarget.fX,
163                                                      y + cy - fTarget.fY,
164                                                      bounds);
165                    SkScalar k = fKernel[cy * fKernelSize.fWidth + cx];
166                    if (convolveAlpha) {
167                        sumA += SkScalarMul(SkIntToScalar(SkGetPackedA32(s)), k);
168                    }
169                    sumR += SkScalarMul(SkIntToScalar(SkGetPackedR32(s)), k);
170                    sumG += SkScalarMul(SkIntToScalar(SkGetPackedG32(s)), k);
171                    sumB += SkScalarMul(SkIntToScalar(SkGetPackedB32(s)), k);
172                }
173            }
174            int a = convolveAlpha
175                  ? SkClampMax(SkScalarFloorToInt(SkScalarMul(sumA, fGain) + fBias), 255)
176                  : 255;
177            int r = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumR, fGain) + fBias), a);
178            int g = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumG, fGain) + fBias), a);
179            int b = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumB, fGain) + fBias), a);
180            if (!convolveAlpha) {
181                a = SkGetPackedA32(PixelFetcher::fetch(src, x, y, bounds));
182                *dptr++ = SkPreMultiplyARGB(a, r, g, b);
183            } else {
184                *dptr++ = SkPackARGB32(a, r, g, b);
185            }
186        }
187    }
188}
189
190template<class PixelFetcher>
191void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src,
192                                                  SkBitmap* result,
193                                                  const SkIRect& rect,
194                                                  const SkIRect& bounds) {
195    if (fConvolveAlpha) {
196        filterPixels<PixelFetcher, true>(src, result, rect, bounds);
197    } else {
198        filterPixels<PixelFetcher, false>(src, result, rect, bounds);
199    }
200}
201
202void SkMatrixConvolutionImageFilter::filterInteriorPixels(const SkBitmap& src,
203                                                          SkBitmap* result,
204                                                          const SkIRect& rect,
205                                                          const SkIRect& bounds) {
206    filterPixels<UncheckedPixelFetcher>(src, result, rect, bounds);
207}
208
209void SkMatrixConvolutionImageFilter::filterBorderPixels(const SkBitmap& src,
210                                                        SkBitmap* result,
211                                                        const SkIRect& rect,
212                                                        const SkIRect& bounds) {
213    switch (fTileMode) {
214        case kClamp_TileMode:
215            filterPixels<ClampPixelFetcher>(src, result, rect, bounds);
216            break;
217        case kRepeat_TileMode:
218            filterPixels<RepeatPixelFetcher>(src, result, rect, bounds);
219            break;
220        case kClampToBlack_TileMode:
221            filterPixels<ClampToBlackPixelFetcher>(src, result, rect, bounds);
222            break;
223    }
224}
225
226// FIXME:  This should be refactored to SkImageFilterUtils for
227// use by other filters.  For now, we assume the input is always
228// premultiplied and unpremultiply it
229static SkBitmap unpremultiplyBitmap(const SkBitmap& src)
230{
231    SkAutoLockPixels alp(src);
232    if (!src.getPixels()) {
233        return SkBitmap();
234    }
235    SkBitmap result;
236    result.setConfig(src.config(), src.width(), src.height());
237    result.allocPixels();
238    if (!result.getPixels()) {
239        return SkBitmap();
240    }
241    for (int y = 0; y < src.height(); ++y) {
242        const uint32_t* srcRow = src.getAddr32(0, y);
243        uint32_t* dstRow = result.getAddr32(0, y);
244        for (int x = 0; x < src.width(); ++x) {
245            dstRow[x] = SkUnPreMultiply::PMColorToColor(srcRow[x]);
246        }
247    }
248    return result;
249}
250
251bool SkMatrixConvolutionImageFilter::onFilterImage(Proxy* proxy,
252                                                   const SkBitmap& source,
253                                                   const SkMatrix& matrix,
254                                                   SkBitmap* result,
255                                                   SkIPoint* loc) {
256    SkBitmap src = source;
257    if (getInput(0) && !getInput(0)->filterImage(proxy, source, matrix, &src, loc)) {
258        return false;
259    }
260
261    if (src.config() != SkBitmap::kARGB_8888_Config) {
262        return false;
263    }
264
265    SkIRect bounds;
266    src.getBounds(&bounds);
267    if (!this->applyCropRect(&bounds, matrix)) {
268        return false;
269    }
270
271    if (!fConvolveAlpha && !src.isOpaque()) {
272        src = unpremultiplyBitmap(src);
273    }
274
275    SkAutoLockPixels alp(src);
276    if (!src.getPixels()) {
277        return false;
278    }
279
280    result->setConfig(src.config(), bounds.width(), bounds.height());
281    result->allocPixels();
282    if (!result->getPixels()) {
283        return false;
284    }
285
286    SkIRect interior = SkIRect::MakeXYWH(bounds.left() + fTarget.fX,
287                                         bounds.top() + fTarget.fY,
288                                         bounds.width() - fKernelSize.fWidth + 1,
289                                         bounds.height() - fKernelSize.fHeight + 1);
290    SkIRect top = SkIRect::MakeLTRB(bounds.left(), bounds.top(), bounds.right(), interior.top());
291    SkIRect bottom = SkIRect::MakeLTRB(bounds.left(), interior.bottom(),
292                                       bounds.right(), bounds.bottom());
293    SkIRect left = SkIRect::MakeLTRB(bounds.left(), interior.top(),
294                                     interior.left(), interior.bottom());
295    SkIRect right = SkIRect::MakeLTRB(interior.right(), interior.top(),
296                                      bounds.right(), interior.bottom());
297    filterBorderPixels(src, result, top, bounds);
298    filterBorderPixels(src, result, left, bounds);
299    filterInteriorPixels(src, result, interior, bounds);
300    filterBorderPixels(src, result, right, bounds);
301    filterBorderPixels(src, result, bottom, bounds);
302    loc->fX += bounds.fLeft;
303    loc->fY += bounds.fTop;
304    return true;
305}
306
307#if SK_SUPPORT_GPU
308
309///////////////////////////////////////////////////////////////////////////////
310
311class GrGLMatrixConvolutionEffect;
312
313class GrMatrixConvolutionEffect : public GrSingleTextureEffect {
314public:
315    typedef SkMatrixConvolutionImageFilter::TileMode TileMode;
316    static GrEffectRef* Create(GrTexture* texture,
317                               const SkIRect& bounds,
318                               const SkISize& kernelSize,
319                               const SkScalar* kernel,
320                               SkScalar gain,
321                               SkScalar bias,
322                               const SkIPoint& target,
323                               TileMode tileMode,
324                               bool convolveAlpha) {
325        AutoEffectUnref effect(SkNEW_ARGS(GrMatrixConvolutionEffect, (texture,
326                                                                      bounds,
327                                                                      kernelSize,
328                                                                      kernel,
329                                                                      gain,
330                                                                      bias,
331                                                                      target,
332                                                                      tileMode,
333                                                                      convolveAlpha)));
334        return CreateEffectRef(effect);
335    }
336    virtual ~GrMatrixConvolutionEffect();
337
338    virtual void getConstantColorComponents(GrColor* color,
339                                            uint32_t* validFlags) const SK_OVERRIDE {
340        // TODO: Try to do better?
341        *validFlags = 0;
342    }
343
344    static const char* Name() { return "MatrixConvolution"; }
345    const SkIRect& bounds() const { return fBounds; }
346    const SkISize& kernelSize() const { return fKernelSize; }
347    const float* target() const { return fTarget; }
348    const float* kernel() const { return fKernel; }
349    float gain() const { return fGain; }
350    float bias() const { return fBias; }
351    TileMode tileMode() const { return fTileMode; }
352    bool convolveAlpha() const { return fConvolveAlpha; }
353
354    typedef GrGLMatrixConvolutionEffect GLEffect;
355
356    virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
357
358private:
359    GrMatrixConvolutionEffect(GrTexture*,
360                              const SkIRect& bounds,
361                              const SkISize& kernelSize,
362                              const SkScalar* kernel,
363                              SkScalar gain,
364                              SkScalar bias,
365                              const SkIPoint& target,
366                              TileMode tileMode,
367                              bool convolveAlpha);
368
369    virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE;
370
371    SkIRect  fBounds;
372    SkISize  fKernelSize;
373    float   *fKernel;
374    float    fGain;
375    float    fBias;
376    float    fTarget[2];
377    TileMode fTileMode;
378    bool     fConvolveAlpha;
379
380    GR_DECLARE_EFFECT_TEST;
381
382    typedef GrSingleTextureEffect INHERITED;
383};
384
385class GrGLMatrixConvolutionEffect : public GrGLEffect {
386public:
387    GrGLMatrixConvolutionEffect(const GrBackendEffectFactory& factory,
388                                const GrDrawEffect& effect);
389    virtual void emitCode(GrGLShaderBuilder*,
390                          const GrDrawEffect&,
391                          EffectKey,
392                          const char* outputColor,
393                          const char* inputColor,
394                          const TransformedCoordsArray&,
395                          const TextureSamplerArray&) SK_OVERRIDE;
396
397    static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
398
399    virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
400
401private:
402    typedef GrGLUniformManager::UniformHandle        UniformHandle;
403    typedef SkMatrixConvolutionImageFilter::TileMode TileMode;
404    SkISize             fKernelSize;
405    TileMode            fTileMode;
406    bool                fConvolveAlpha;
407
408    UniformHandle       fBoundsUni;
409    UniformHandle       fKernelUni;
410    UniformHandle       fImageIncrementUni;
411    UniformHandle       fTargetUni;
412    UniformHandle       fGainUni;
413    UniformHandle       fBiasUni;
414
415    typedef GrGLEffect INHERITED;
416};
417
418GrGLMatrixConvolutionEffect::GrGLMatrixConvolutionEffect(const GrBackendEffectFactory& factory,
419                                                         const GrDrawEffect& drawEffect)
420    : INHERITED(factory) {
421    const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
422    fKernelSize = m.kernelSize();
423    fTileMode = m.tileMode();
424    fConvolveAlpha = m.convolveAlpha();
425}
426
427static void appendTextureLookup(GrGLShaderBuilder* builder,
428                                const GrGLShaderBuilder::TextureSampler& sampler,
429                                const char* coord,
430                                const char* bounds,
431                                SkMatrixConvolutionImageFilter::TileMode tileMode) {
432    SkString clampedCoord;
433    switch (tileMode) {
434        case SkMatrixConvolutionImageFilter::kClamp_TileMode:
435            clampedCoord.printf("clamp(%s, %s.xy, %s.zw)", coord, bounds, bounds);
436            coord = clampedCoord.c_str();
437            break;
438        case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
439            clampedCoord.printf("mod(%s - %s.xy, %s.zw - %s.xy) + %s.xy", coord, bounds, bounds, bounds, bounds);
440            coord = clampedCoord.c_str();
441            break;
442        case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
443            builder->fsCodeAppendf("clamp(%s, %s.xy, %s.zw) != %s ? vec4(0, 0, 0, 0) : ", coord, bounds, bounds, coord);
444            break;
445    }
446    builder->fsAppendTextureLookup(sampler, coord);
447}
448
449void GrGLMatrixConvolutionEffect::emitCode(GrGLShaderBuilder* builder,
450                                           const GrDrawEffect&,
451                                           EffectKey key,
452                                           const char* outputColor,
453                                           const char* inputColor,
454                                           const TransformedCoordsArray& coords,
455                                           const TextureSamplerArray& samplers) {
456    sk_ignore_unused_variable(inputColor);
457    SkString coords2D = builder->ensureFSCoords2D(coords, 0);
458    fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
459                                     kVec4f_GrSLType, "Bounds");
460    fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
461                                             kVec2f_GrSLType, "ImageIncrement");
462    fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
463                                             kFloat_GrSLType,
464                                             "Kernel",
465                                             fKernelSize.width() * fKernelSize.height());
466    fTargetUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
467                                             kVec2f_GrSLType, "Target");
468    fGainUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
469                                   kFloat_GrSLType, "Gain");
470    fBiasUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
471                                   kFloat_GrSLType, "Bias");
472
473    const char* bounds = builder->getUniformCStr(fBoundsUni);
474    const char* target = builder->getUniformCStr(fTargetUni);
475    const char* imgInc = builder->getUniformCStr(fImageIncrementUni);
476    const char* kernel = builder->getUniformCStr(fKernelUni);
477    const char* gain = builder->getUniformCStr(fGainUni);
478    const char* bias = builder->getUniformCStr(fBiasUni);
479    int kWidth = fKernelSize.width();
480    int kHeight = fKernelSize.height();
481
482    builder->fsCodeAppend("\t\tvec4 sum = vec4(0, 0, 0, 0);\n");
483    builder->fsCodeAppendf("\t\tvec2 coord = %s - %s * %s;\n", coords2D.c_str(), target, imgInc);
484    builder->fsCodeAppendf("\t\tfor (int y = 0; y < %d; y++) {\n", kHeight);
485    builder->fsCodeAppendf("\t\t\tfor (int x = 0; x < %d; x++) {\n", kWidth);
486    builder->fsCodeAppendf("\t\t\t\tfloat k = %s[y * %d + x];\n", kernel, kWidth);
487    builder->fsCodeAppendf("\t\t\t\tvec2 coord2 = coord + vec2(x, y) * %s;\n", imgInc);
488    builder->fsCodeAppend("\t\t\t\tvec4 c = ");
489    appendTextureLookup(builder, samplers[0], "coord2", bounds, fTileMode);
490    builder->fsCodeAppend(";\n");
491    if (!fConvolveAlpha) {
492        builder->fsCodeAppend("\t\t\t\tc.rgb /= c.a;\n");
493    }
494    builder->fsCodeAppend("\t\t\t\tsum += c * k;\n");
495    builder->fsCodeAppend("\t\t\t}\n");
496    builder->fsCodeAppend("\t\t}\n");
497    if (fConvolveAlpha) {
498        builder->fsCodeAppendf("\t\t%s = sum * %s + %s;\n", outputColor, gain, bias);
499        builder->fsCodeAppendf("\t\t%s.rgb = clamp(%s.rgb, 0.0, %s.a);\n",
500            outputColor, outputColor, outputColor);
501    } else {
502        builder->fsCodeAppend("\t\tvec4 c = ");
503        appendTextureLookup(builder, samplers[0], coords2D.c_str(), bounds, fTileMode);
504        builder->fsCodeAppend(";\n");
505        builder->fsCodeAppendf("\t\t%s.a = c.a;\n", outputColor);
506        builder->fsCodeAppendf("\t\t%s.rgb = sum.rgb * %s + %s;\n", outputColor, gain, bias);
507        builder->fsCodeAppendf("\t\t%s.rgb *= %s.a;\n", outputColor, outputColor);
508    }
509}
510
511namespace {
512
513int encodeXY(int x, int y) {
514    SkASSERT(x >= 1 && y >= 1 && x * y <= 32);
515    if (y < x)
516        return 0x40 | encodeXY(y, x);
517    else
518        return (0x40 >> x) | (y - x);
519}
520
521};
522
523GrGLEffect::EffectKey GrGLMatrixConvolutionEffect::GenKey(const GrDrawEffect& drawEffect,
524                                                          const GrGLCaps&) {
525    const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
526    EffectKey key = encodeXY(m.kernelSize().width(), m.kernelSize().height());
527    key |= m.tileMode() << 7;
528    key |= m.convolveAlpha() ? 1 << 9 : 0;
529    return key;
530}
531
532void GrGLMatrixConvolutionEffect::setData(const GrGLUniformManager& uman,
533                                          const GrDrawEffect& drawEffect) {
534    const GrMatrixConvolutionEffect& conv = drawEffect.castEffect<GrMatrixConvolutionEffect>();
535    GrTexture& texture = *conv.texture(0);
536    // the code we generated was for a specific kernel size
537    SkASSERT(conv.kernelSize() == fKernelSize);
538    SkASSERT(conv.tileMode() == fTileMode);
539    float imageIncrement[2];
540    float ySign = texture.origin() == kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
541    imageIncrement[0] = 1.0f / texture.width();
542    imageIncrement[1] = ySign / texture.height();
543    uman.set2fv(fImageIncrementUni, 1, imageIncrement);
544    uman.set2fv(fTargetUni, 1, conv.target());
545    uman.set1fv(fKernelUni, fKernelSize.width() * fKernelSize.height(), conv.kernel());
546    uman.set1f(fGainUni, conv.gain());
547    uman.set1f(fBiasUni, conv.bias());
548    const SkIRect& bounds = conv.bounds();
549    float left = (float) bounds.left() / texture.width();
550    float top = (float) bounds.top() / texture.height();
551    float right = (float) bounds.right() / texture.width();
552    float bottom = (float) bounds.bottom() / texture.height();
553    if (texture.origin() == kBottomLeft_GrSurfaceOrigin) {
554        uman.set4f(fBoundsUni, left, 1.0f - bottom, right, 1.0f - top);
555    } else {
556        uman.set4f(fBoundsUni, left, top, right, bottom);
557    }
558}
559
560GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrTexture* texture,
561                                                     const SkIRect& bounds,
562                                                     const SkISize& kernelSize,
563                                                     const SkScalar* kernel,
564                                                     SkScalar gain,
565                                                     SkScalar bias,
566                                                     const SkIPoint& target,
567                                                     TileMode tileMode,
568                                                     bool convolveAlpha)
569  : INHERITED(texture, MakeDivByTextureWHMatrix(texture)),
570    fBounds(bounds),
571    fKernelSize(kernelSize),
572    fGain(SkScalarToFloat(gain)),
573    fBias(SkScalarToFloat(bias) / 255.0f),
574    fTileMode(tileMode),
575    fConvolveAlpha(convolveAlpha) {
576    fKernel = new float[kernelSize.width() * kernelSize.height()];
577    for (int i = 0; i < kernelSize.width() * kernelSize.height(); i++) {
578        fKernel[i] = SkScalarToFloat(kernel[i]);
579    }
580    fTarget[0] = static_cast<float>(target.x());
581    fTarget[1] = static_cast<float>(target.y());
582    this->setWillNotUseInputColor();
583}
584
585GrMatrixConvolutionEffect::~GrMatrixConvolutionEffect() {
586    delete[] fKernel;
587}
588
589const GrBackendEffectFactory& GrMatrixConvolutionEffect::getFactory() const {
590    return GrTBackendEffectFactory<GrMatrixConvolutionEffect>::getInstance();
591}
592
593bool GrMatrixConvolutionEffect::onIsEqual(const GrEffect& sBase) const {
594    const GrMatrixConvolutionEffect& s = CastEffect<GrMatrixConvolutionEffect>(sBase);
595    return this->texture(0) == s.texture(0) &&
596           fKernelSize == s.kernelSize() &&
597           !memcmp(fKernel, s.kernel(),
598                   fKernelSize.width() * fKernelSize.height() * sizeof(float)) &&
599           fGain == s.gain() &&
600           fBias == s.bias() &&
601           fTarget == s.target() &&
602           fTileMode == s.tileMode() &&
603           fConvolveAlpha == s.convolveAlpha();
604}
605
606GR_DEFINE_EFFECT_TEST(GrMatrixConvolutionEffect);
607
608// A little bit less than the minimum # uniforms required by DX9SM2 (32).
609// Allows for a 5x5 kernel (or 25x1, for that matter).
610#define MAX_KERNEL_SIZE 25
611
612GrEffectRef* GrMatrixConvolutionEffect::TestCreate(SkRandom* random,
613                                                   GrContext* context,
614                                                   const GrDrawTargetCaps&,
615                                                   GrTexture* textures[]) {
616    int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
617                                      GrEffectUnitTest::kAlphaTextureIdx;
618    int width = random->nextRangeU(1, MAX_KERNEL_SIZE);
619    int height = random->nextRangeU(1, MAX_KERNEL_SIZE / width);
620    SkISize kernelSize = SkISize::Make(width, height);
621    SkAutoTDeleteArray<SkScalar> kernel(new SkScalar[width * height]);
622    for (int i = 0; i < width * height; i++) {
623        kernel.get()[i] = random->nextSScalar1();
624    }
625    SkScalar gain = random->nextSScalar1();
626    SkScalar bias = random->nextSScalar1();
627    SkIPoint target = SkIPoint::Make(random->nextRangeU(0, kernelSize.width()),
628                                     random->nextRangeU(0, kernelSize.height()));
629    SkIRect bounds = SkIRect::MakeXYWH(random->nextRangeU(0, textures[texIdx]->width()),
630                                       random->nextRangeU(0, textures[texIdx]->height()),
631                                       random->nextRangeU(0, textures[texIdx]->width()),
632                                       random->nextRangeU(0, textures[texIdx]->height()));
633    TileMode tileMode = static_cast<TileMode>(random->nextRangeU(0, 2));
634    bool convolveAlpha = random->nextBool();
635    return GrMatrixConvolutionEffect::Create(textures[texIdx],
636                                             bounds,
637                                             kernelSize,
638                                             kernel.get(),
639                                             gain,
640                                             bias,
641                                             target,
642                                             tileMode,
643                                             convolveAlpha);
644}
645
646bool SkMatrixConvolutionImageFilter::asNewEffect(GrEffectRef** effect,
647                                                 GrTexture* texture,
648                                                 const SkMatrix&,
649                                                 const SkIRect& bounds
650                                                 ) const {
651    if (!effect) {
652        return fKernelSize.width() * fKernelSize.height() <= MAX_KERNEL_SIZE;
653    }
654    SkASSERT(fKernelSize.width() * fKernelSize.height() <= MAX_KERNEL_SIZE);
655    *effect = GrMatrixConvolutionEffect::Create(texture,
656                                                bounds,
657                                                fKernelSize,
658                                                fKernel,
659                                                fGain,
660                                                fBias,
661                                                fTarget,
662                                                fTileMode,
663                                                fConvolveAlpha);
664    return true;
665}
666
667///////////////////////////////////////////////////////////////////////////////
668
669#endif
670