SkMatrixConvolutionImageFilter.cpp revision c0b7e10c6a68f59e1653e6c18e6bc954b3c3f0cf 
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(buffer) {
62    fKernelSize.fWidth = buffer.readInt();
63    fKernelSize.fHeight = buffer.readInt();
64    uint32_t size = fKernelSize.fWidth * fKernelSize.fHeight;
65    fKernel = SkNEW_ARRAY(SkScalar, size);
66    SkDEBUGCODE(uint32_t readSize = )buffer.readScalarArray(fKernel);
67    SkASSERT(readSize == size);
68    fGain = buffer.readScalar();
69    fBias = buffer.readScalar();
70    fTarget.fX = buffer.readInt();
71    fTarget.fY = buffer.readInt();
72    fTileMode = (TileMode) buffer.readInt();
73    fConvolveAlpha = buffer.readBool();
74    buffer.validate(SkScalarIsFinite(fGain) &&
75                    SkScalarIsFinite(fBias) &&
76                    tile_mode_is_valid(fTileMode));
77}
78
79void SkMatrixConvolutionImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
80    this->INHERITED::flatten(buffer);
81    buffer.writeInt(fKernelSize.fWidth);
82    buffer.writeInt(fKernelSize.fHeight);
83    buffer.writeScalarArray(fKernel, fKernelSize.fWidth * fKernelSize.fHeight);
84    buffer.writeScalar(fGain);
85    buffer.writeScalar(fBias);
86    buffer.writeInt(fTarget.fX);
87    buffer.writeInt(fTarget.fY);
88    buffer.writeInt((int) fTileMode);
89    buffer.writeBool(fConvolveAlpha);
90}
91
92SkMatrixConvolutionImageFilter::~SkMatrixConvolutionImageFilter() {
93    delete[] fKernel;
94}
95
96class UncheckedPixelFetcher {
97public:
98    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
99        return *src.getAddr32(x, y);
100    }
101};
102
103class ClampPixelFetcher {
104public:
105    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
106        x = SkPin32(x, bounds.fLeft, bounds.fRight - 1);
107        y = SkPin32(y, bounds.fTop, bounds.fBottom - 1);
108        return *src.getAddr32(x, y);
109    }
110};
111
112class RepeatPixelFetcher {
113public:
114    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
115        x = (x - bounds.left()) % bounds.width() + bounds.left();
116        y = (y - bounds.top()) % bounds.height() + bounds.top();
117        if (x < bounds.left()) {
118            x += bounds.width();
119        }
120        if (y < bounds.top()) {
121            y += bounds.height();
122        }
123        return *src.getAddr32(x, y);
124    }
125};
126
127class ClampToBlackPixelFetcher {
128public:
129    static inline SkPMColor fetch(const SkBitmap& src, int x, int y, const SkIRect& bounds) {
130        if (x < bounds.fLeft || x >= bounds.fRight || y < bounds.fTop || y >= bounds.fBottom) {
131            return 0;
132        } else {
133            return *src.getAddr32(x, y);
134        }
135    }
136};
137
138template<class PixelFetcher, bool convolveAlpha>
139void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src,
140                                                  SkBitmap* result,
141                                                  const SkIRect& rect,
142                                                  const SkIRect& bounds) {
143    for (int y = rect.fTop; y < rect.fBottom; ++y) {
144        SkPMColor* dptr = result->getAddr32(rect.fLeft - bounds.fLeft, y - bounds.fTop);
145        for (int x = rect.fLeft; x < rect.fRight; ++x) {
146            SkScalar sumA = 0, sumR = 0, sumG = 0, sumB = 0;
147            for (int cy = 0; cy < fKernelSize.fHeight; cy++) {
148                for (int cx = 0; cx < fKernelSize.fWidth; cx++) {
149                    SkPMColor s = PixelFetcher::fetch(src,
150                                                      x + cx - fTarget.fX,
151                                                      y + cy - fTarget.fY,
152                                                      bounds);
153                    SkScalar k = fKernel[cy * fKernelSize.fWidth + cx];
154                    if (convolveAlpha) {
155                        sumA += SkScalarMul(SkIntToScalar(SkGetPackedA32(s)), k);
156                    }
157                    sumR += SkScalarMul(SkIntToScalar(SkGetPackedR32(s)), k);
158                    sumG += SkScalarMul(SkIntToScalar(SkGetPackedG32(s)), k);
159                    sumB += SkScalarMul(SkIntToScalar(SkGetPackedB32(s)), k);
160                }
161            }
162            int a = convolveAlpha
163                  ? SkClampMax(SkScalarFloorToInt(SkScalarMul(sumA, fGain) + fBias), 255)
164                  : 255;
165            int r = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumR, fGain) + fBias), a);
166            int g = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumG, fGain) + fBias), a);
167            int b = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumB, fGain) + fBias), a);
168            if (!convolveAlpha) {
169                a = SkGetPackedA32(PixelFetcher::fetch(src, x, y, bounds));
170                *dptr++ = SkPreMultiplyARGB(a, r, g, b);
171            } else {
172                *dptr++ = SkPackARGB32(a, r, g, b);
173            }
174        }
175    }
176}
177
178template<class PixelFetcher>
179void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src,
180                                                  SkBitmap* result,
181                                                  const SkIRect& rect,
182                                                  const SkIRect& bounds) {
183    if (fConvolveAlpha) {
184        filterPixels<PixelFetcher, true>(src, result, rect, bounds);
185    } else {
186        filterPixels<PixelFetcher, false>(src, result, rect, bounds);
187    }
188}
189
190void SkMatrixConvolutionImageFilter::filterInteriorPixels(const SkBitmap& src,
191                                                          SkBitmap* result,
192                                                          const SkIRect& rect,
193                                                          const SkIRect& bounds) {
194    filterPixels<UncheckedPixelFetcher>(src, result, rect, bounds);
195}
196
197void SkMatrixConvolutionImageFilter::filterBorderPixels(const SkBitmap& src,
198                                                        SkBitmap* result,
199                                                        const SkIRect& rect,
200                                                        const SkIRect& bounds) {
201    switch (fTileMode) {
202        case kClamp_TileMode:
203            filterPixels<ClampPixelFetcher>(src, result, rect, bounds);
204            break;
205        case kRepeat_TileMode:
206            filterPixels<RepeatPixelFetcher>(src, result, rect, bounds);
207            break;
208        case kClampToBlack_TileMode:
209            filterPixels<ClampToBlackPixelFetcher>(src, result, rect, bounds);
210            break;
211    }
212}
213
214// FIXME:  This should be refactored to SkImageFilterUtils for
215// use by other filters.  For now, we assume the input is always
216// premultiplied and unpremultiply it
217static SkBitmap unpremultiplyBitmap(const SkBitmap& src)
218{
219    SkAutoLockPixels alp(src);
220    if (!src.getPixels()) {
221        return SkBitmap();
222    }
223    SkBitmap result;
224    result.setConfig(src.config(), src.width(), src.height());
225    result.allocPixels();
226    if (!result.getPixels()) {
227        return SkBitmap();
228    }
229    for (int y = 0; y < src.height(); ++y) {
230        const uint32_t* srcRow = src.getAddr32(0, y);
231        uint32_t* dstRow = result.getAddr32(0, y);
232        for (int x = 0; x < src.width(); ++x) {
233            dstRow[x] = SkUnPreMultiply::PMColorToColor(srcRow[x]);
234        }
235    }
236    return result;
237}
238
239bool SkMatrixConvolutionImageFilter::onFilterImage(Proxy* proxy,
240                                                   const SkBitmap& source,
241                                                   const SkMatrix& matrix,
242                                                   SkBitmap* result,
243                                                   SkIPoint* loc) {
244    SkBitmap src = source;
245    if (getInput(0) && !getInput(0)->filterImage(proxy, source, matrix, &src, loc)) {
246        return false;
247    }
248
249    if (src.config() != SkBitmap::kARGB_8888_Config) {
250        return false;
251    }
252
253    SkIRect bounds;
254    src.getBounds(&bounds);
255    if (!this->applyCropRect(&bounds, matrix)) {
256        return false;
257    }
258
259    if (!fConvolveAlpha && !src.isOpaque()) {
260        src = unpremultiplyBitmap(src);
261    }
262
263    SkAutoLockPixels alp(src);
264    if (!src.getPixels()) {
265        return false;
266    }
267
268    result->setConfig(src.config(), bounds.width(), bounds.height());
269    result->allocPixels();
270
271    SkIRect interior = SkIRect::MakeXYWH(bounds.left() + fTarget.fX,
272                                         bounds.top() + fTarget.fY,
273                                         bounds.width() - fKernelSize.fWidth + 1,
274                                         bounds.height() - fKernelSize.fHeight + 1);
275    SkIRect top = SkIRect::MakeLTRB(bounds.left(), bounds.top(), bounds.right(), interior.top());
276    SkIRect bottom = SkIRect::MakeLTRB(bounds.left(), interior.bottom(),
277                                       bounds.right(), bounds.bottom());
278    SkIRect left = SkIRect::MakeLTRB(bounds.left(), interior.top(),
279                                     interior.left(), interior.bottom());
280    SkIRect right = SkIRect::MakeLTRB(interior.right(), interior.top(),
281                                      bounds.right(), interior.bottom());
282    filterBorderPixels(src, result, top, bounds);
283    filterBorderPixels(src, result, left, bounds);
284    filterInteriorPixels(src, result, interior, bounds);
285    filterBorderPixels(src, result, right, bounds);
286    filterBorderPixels(src, result, bottom, bounds);
287    loc->fX += bounds.fLeft;
288    loc->fY += bounds.fTop;
289    return true;
290}
291
292#if SK_SUPPORT_GPU
293
294///////////////////////////////////////////////////////////////////////////////
295
296class GrGLMatrixConvolutionEffect;
297
298class GrMatrixConvolutionEffect : public GrSingleTextureEffect {
299public:
300    typedef SkMatrixConvolutionImageFilter::TileMode TileMode;
301    static GrEffectRef* Create(GrTexture* texture,
302                               const SkIRect& bounds,
303                               const SkISize& kernelSize,
304                               const SkScalar* kernel,
305                               SkScalar gain,
306                               SkScalar bias,
307                               const SkIPoint& target,
308                               TileMode tileMode,
309                               bool convolveAlpha) {
310        AutoEffectUnref effect(SkNEW_ARGS(GrMatrixConvolutionEffect, (texture,
311                                                                      bounds,
312                                                                      kernelSize,
313                                                                      kernel,
314                                                                      gain,
315                                                                      bias,
316                                                                      target,
317                                                                      tileMode,
318                                                                      convolveAlpha)));
319        return CreateEffectRef(effect);
320    }
321    virtual ~GrMatrixConvolutionEffect();
322
323    virtual void getConstantColorComponents(GrColor* color,
324                                            uint32_t* validFlags) const SK_OVERRIDE {
325        // TODO: Try to do better?
326        *validFlags = 0;
327    }
328
329    static const char* Name() { return "MatrixConvolution"; }
330    const SkIRect& bounds() const { return fBounds; }
331    const SkISize& kernelSize() const { return fKernelSize; }
332    const float* target() const { return fTarget; }
333    const float* kernel() const { return fKernel; }
334    float gain() const { return fGain; }
335    float bias() const { return fBias; }
336    TileMode tileMode() const { return fTileMode; }
337    bool convolveAlpha() const { return fConvolveAlpha; }
338
339    typedef GrGLMatrixConvolutionEffect GLEffect;
340
341    virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
342
343private:
344    GrMatrixConvolutionEffect(GrTexture*,
345                              const SkIRect& bounds,
346                              const SkISize& kernelSize,
347                              const SkScalar* kernel,
348                              SkScalar gain,
349                              SkScalar bias,
350                              const SkIPoint& target,
351                              TileMode tileMode,
352                              bool convolveAlpha);
353
354    virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE;
355
356    SkIRect  fBounds;
357    SkISize  fKernelSize;
358    float   *fKernel;
359    float    fGain;
360    float    fBias;
361    float    fTarget[2];
362    TileMode fTileMode;
363    bool     fConvolveAlpha;
364
365    GR_DECLARE_EFFECT_TEST;
366
367    typedef GrSingleTextureEffect INHERITED;
368};
369
370class GrGLMatrixConvolutionEffect : public GrGLEffect {
371public:
372    GrGLMatrixConvolutionEffect(const GrBackendEffectFactory& factory,
373                                const GrDrawEffect& effect);
374    virtual void emitCode(GrGLShaderBuilder*,
375                          const GrDrawEffect&,
376                          EffectKey,
377                          const char* outputColor,
378                          const char* inputColor,
379                          const TransformedCoordsArray&,
380                          const TextureSamplerArray&) SK_OVERRIDE;
381
382    static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
383
384    virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
385
386private:
387    typedef GrGLUniformManager::UniformHandle        UniformHandle;
388    typedef SkMatrixConvolutionImageFilter::TileMode TileMode;
389    SkISize             fKernelSize;
390    TileMode            fTileMode;
391    bool                fConvolveAlpha;
392
393    UniformHandle       fBoundsUni;
394    UniformHandle       fKernelUni;
395    UniformHandle       fImageIncrementUni;
396    UniformHandle       fTargetUni;
397    UniformHandle       fGainUni;
398    UniformHandle       fBiasUni;
399
400    typedef GrGLEffect INHERITED;
401};
402
403GrGLMatrixConvolutionEffect::GrGLMatrixConvolutionEffect(const GrBackendEffectFactory& factory,
404                                                         const GrDrawEffect& drawEffect)
405    : INHERITED(factory) {
406    const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
407    fKernelSize = m.kernelSize();
408    fTileMode = m.tileMode();
409    fConvolveAlpha = m.convolveAlpha();
410}
411
412static void appendTextureLookup(GrGLShaderBuilder* builder,
413                                const GrGLShaderBuilder::TextureSampler& sampler,
414                                const char* coord,
415                                const char* bounds,
416                                SkMatrixConvolutionImageFilter::TileMode tileMode) {
417    SkString clampedCoord;
418    switch (tileMode) {
419        case SkMatrixConvolutionImageFilter::kClamp_TileMode:
420            clampedCoord.printf("clamp(%s, %s.xy, %s.zw)", coord, bounds, bounds);
421            coord = clampedCoord.c_str();
422            break;
423        case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
424            clampedCoord.printf("mod(%s - %s.xy, %s.zw - %s.xy) + %s.xy", coord, bounds, bounds, bounds, bounds);
425            coord = clampedCoord.c_str();
426            break;
427        case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
428            builder->fsCodeAppendf("clamp(%s, %s.xy, %s.zw) != %s ? vec4(0, 0, 0, 0) : ", coord, bounds, bounds, coord);
429            break;
430    }
431    builder->fsAppendTextureLookup(sampler, coord);
432}
433
434void GrGLMatrixConvolutionEffect::emitCode(GrGLShaderBuilder* builder,
435                                           const GrDrawEffect&,
436                                           EffectKey key,
437                                           const char* outputColor,
438                                           const char* inputColor,
439                                           const TransformedCoordsArray& coords,
440                                           const TextureSamplerArray& samplers) {
441    sk_ignore_unused_variable(inputColor);
442    SkString coords2D = builder->ensureFSCoords2D(coords, 0);
443    fBoundsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
444                                     kVec4f_GrSLType, "Bounds");
445    fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
446                                             kVec2f_GrSLType, "ImageIncrement");
447    fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
448                                             kFloat_GrSLType,
449                                             "Kernel",
450                                             fKernelSize.width() * fKernelSize.height());
451    fTargetUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
452                                             kVec2f_GrSLType, "Target");
453    fGainUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
454                                   kFloat_GrSLType, "Gain");
455    fBiasUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
456                                   kFloat_GrSLType, "Bias");
457
458    const char* bounds = builder->getUniformCStr(fBoundsUni);
459    const char* target = builder->getUniformCStr(fTargetUni);
460    const char* imgInc = builder->getUniformCStr(fImageIncrementUni);
461    const char* kernel = builder->getUniformCStr(fKernelUni);
462    const char* gain = builder->getUniformCStr(fGainUni);
463    const char* bias = builder->getUniformCStr(fBiasUni);
464    int kWidth = fKernelSize.width();
465    int kHeight = fKernelSize.height();
466
467    builder->fsCodeAppend("\t\tvec4 sum = vec4(0, 0, 0, 0);\n");
468    builder->fsCodeAppendf("\t\tvec2 coord = %s - %s * %s;\n", coords2D.c_str(), target, imgInc);
469    builder->fsCodeAppendf("\t\tfor (int y = 0; y < %d; y++) {\n", kHeight);
470    builder->fsCodeAppendf("\t\t\tfor (int x = 0; x < %d; x++) {\n", kWidth);
471    builder->fsCodeAppendf("\t\t\t\tfloat k = %s[y * %d + x];\n", kernel, kWidth);
472    builder->fsCodeAppendf("\t\t\t\tvec2 coord2 = coord + vec2(x, y) * %s;\n", imgInc);
473    builder->fsCodeAppend("\t\t\t\tvec4 c = ");
474    appendTextureLookup(builder, samplers[0], "coord2", bounds, fTileMode);
475    builder->fsCodeAppend(";\n");
476    if (!fConvolveAlpha) {
477        builder->fsCodeAppend("\t\t\t\tc.rgb /= c.a;\n");
478    }
479    builder->fsCodeAppend("\t\t\t\tsum += c * k;\n");
480    builder->fsCodeAppend("\t\t\t}\n");
481    builder->fsCodeAppend("\t\t}\n");
482    if (fConvolveAlpha) {
483        builder->fsCodeAppendf("\t\t%s = sum * %s + %s;\n", outputColor, gain, bias);
484        builder->fsCodeAppendf("\t\t%s.rgb = clamp(%s.rgb, 0.0, %s.a);\n",
485            outputColor, outputColor, outputColor);
486    } else {
487        builder->fsCodeAppend("\t\tvec4 c = ");
488        appendTextureLookup(builder, samplers[0], coords2D.c_str(), bounds, fTileMode);
489        builder->fsCodeAppend(";\n");
490        builder->fsCodeAppendf("\t\t%s.a = c.a;\n", outputColor);
491        builder->fsCodeAppendf("\t\t%s.rgb = sum.rgb * %s + %s;\n", outputColor, gain, bias);
492        builder->fsCodeAppendf("\t\t%s.rgb *= %s.a;\n", outputColor, outputColor);
493    }
494}
495
496namespace {
497
498int encodeXY(int x, int y) {
499    SkASSERT(x >= 1 && y >= 1 && x * y <= 32);
500    if (y < x)
501        return 0x40 | encodeXY(y, x);
502    else
503        return (0x40 >> x) | (y - x);
504}
505
506};
507
508GrGLEffect::EffectKey GrGLMatrixConvolutionEffect::GenKey(const GrDrawEffect& drawEffect,
509                                                          const GrGLCaps&) {
510    const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
511    EffectKey key = encodeXY(m.kernelSize().width(), m.kernelSize().height());
512    key |= m.tileMode() << 7;
513    key |= m.convolveAlpha() ? 1 << 9 : 0;
514    return key;
515}
516
517void GrGLMatrixConvolutionEffect::setData(const GrGLUniformManager& uman,
518                                          const GrDrawEffect& drawEffect) {
519    const GrMatrixConvolutionEffect& conv = drawEffect.castEffect<GrMatrixConvolutionEffect>();
520    GrTexture& texture = *conv.texture(0);
521    // the code we generated was for a specific kernel size
522    SkASSERT(conv.kernelSize() == fKernelSize);
523    SkASSERT(conv.tileMode() == fTileMode);
524    float imageIncrement[2];
525    float ySign = texture.origin() == kTopLeft_GrSurfaceOrigin ? 1.0f : -1.0f;
526    imageIncrement[0] = 1.0f / texture.width();
527    imageIncrement[1] = ySign / texture.height();
528    uman.set2fv(fImageIncrementUni, 0, 1, imageIncrement);
529    uman.set2fv(fTargetUni, 0, 1, conv.target());
530    uman.set1fv(fKernelUni, 0, fKernelSize.width() * fKernelSize.height(), conv.kernel());
531    uman.set1f(fGainUni, conv.gain());
532    uman.set1f(fBiasUni, conv.bias());
533    const SkIRect& bounds = conv.bounds();
534    float left = (float) bounds.left() / texture.width();
535    float top = (float) bounds.top() / texture.height();
536    float right = (float) bounds.right() / texture.width();
537    float bottom = (float) bounds.bottom() / texture.height();
538    if (texture.origin() == kBottomLeft_GrSurfaceOrigin) {
539        uman.set4f(fBoundsUni, left, 1.0f - bottom, right, 1.0f - top);
540    } else {
541        uman.set4f(fBoundsUni, left, top, right, bottom);
542    }
543}
544
545GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrTexture* texture,
546                                                     const SkIRect& bounds,
547                                                     const SkISize& kernelSize,
548                                                     const SkScalar* kernel,
549                                                     SkScalar gain,
550                                                     SkScalar bias,
551                                                     const SkIPoint& target,
552                                                     TileMode tileMode,
553                                                     bool convolveAlpha)
554  : INHERITED(texture, MakeDivByTextureWHMatrix(texture)),
555    fBounds(bounds),
556    fKernelSize(kernelSize),
557    fGain(SkScalarToFloat(gain)),
558    fBias(SkScalarToFloat(bias) / 255.0f),
559    fTileMode(tileMode),
560    fConvolveAlpha(convolveAlpha) {
561    fKernel = new float[kernelSize.width() * kernelSize.height()];
562    for (int i = 0; i < kernelSize.width() * kernelSize.height(); i++) {
563        fKernel[i] = SkScalarToFloat(kernel[i]);
564    }
565    fTarget[0] = static_cast<float>(target.x());
566    fTarget[1] = static_cast<float>(target.y());
567    this->setWillNotUseInputColor();
568}
569
570GrMatrixConvolutionEffect::~GrMatrixConvolutionEffect() {
571    delete[] fKernel;
572}
573
574const GrBackendEffectFactory& GrMatrixConvolutionEffect::getFactory() const {
575    return GrTBackendEffectFactory<GrMatrixConvolutionEffect>::getInstance();
576}
577
578bool GrMatrixConvolutionEffect::onIsEqual(const GrEffect& sBase) const {
579    const GrMatrixConvolutionEffect& s = CastEffect<GrMatrixConvolutionEffect>(sBase);
580    return this->texture(0) == s.texture(0) &&
581           fKernelSize == s.kernelSize() &&
582           !memcmp(fKernel, s.kernel(),
583                   fKernelSize.width() * fKernelSize.height() * sizeof(float)) &&
584           fGain == s.gain() &&
585           fBias == s.bias() &&
586           fTarget == s.target() &&
587           fTileMode == s.tileMode() &&
588           fConvolveAlpha == s.convolveAlpha();
589}
590
591GR_DEFINE_EFFECT_TEST(GrMatrixConvolutionEffect);
592
593// A little bit less than the minimum # uniforms required by DX9SM2 (32).
594// Allows for a 5x5 kernel (or 25x1, for that matter).
595#define MAX_KERNEL_SIZE 25
596
597GrEffectRef* GrMatrixConvolutionEffect::TestCreate(SkRandom* random,
598                                                   GrContext* context,
599                                                   const GrDrawTargetCaps&,
600                                                   GrTexture* textures[]) {
601    int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
602                                      GrEffectUnitTest::kAlphaTextureIdx;
603    int width = random->nextRangeU(1, MAX_KERNEL_SIZE);
604    int height = random->nextRangeU(1, MAX_KERNEL_SIZE / width);
605    SkISize kernelSize = SkISize::Make(width, height);
606    SkAutoTDeleteArray<SkScalar> kernel(new SkScalar[width * height]);
607    for (int i = 0; i < width * height; i++) {
608        kernel.get()[i] = random->nextSScalar1();
609    }
610    SkScalar gain = random->nextSScalar1();
611    SkScalar bias = random->nextSScalar1();
612    SkIPoint target = SkIPoint::Make(random->nextRangeU(0, kernelSize.width()),
613                                     random->nextRangeU(0, kernelSize.height()));
614    SkIRect bounds = SkIRect::MakeXYWH(random->nextRangeU(0, textures[texIdx]->width()),
615                                       random->nextRangeU(0, textures[texIdx]->height()),
616                                       random->nextRangeU(0, textures[texIdx]->width()),
617                                       random->nextRangeU(0, textures[texIdx]->height()));
618    TileMode tileMode = static_cast<TileMode>(random->nextRangeU(0, 2));
619    bool convolveAlpha = random->nextBool();
620    return GrMatrixConvolutionEffect::Create(textures[texIdx],
621                                             bounds,
622                                             kernelSize,
623                                             kernel.get(),
624                                             gain,
625                                             bias,
626                                             target,
627                                             tileMode,
628                                             convolveAlpha);
629}
630
631bool SkMatrixConvolutionImageFilter::asNewEffect(GrEffectRef** effect,
632                                                 GrTexture* texture,
633                                                 const SkMatrix&,
634                                                 const SkIRect& bounds
635                                                 ) const {
636    if (!effect) {
637        return fKernelSize.width() * fKernelSize.height() <= MAX_KERNEL_SIZE;
638    }
639    SkASSERT(fKernelSize.width() * fKernelSize.height() <= MAX_KERNEL_SIZE);
640    *effect = GrMatrixConvolutionEffect::Create(texture,
641                                                bounds,
642                                                fKernelSize,
643                                                fKernel,
644                                                fGain,
645                                                fBias,
646                                                fTarget,
647                                                fTileMode,
648                                                fConvolveAlpha);
649    return true;
650}
651
652///////////////////////////////////////////////////////////////////////////////
653
654#endif
655