SkMatrixConvolutionImageFilter.cpp revision 159d42b546f94fdc5972f3fbdfde9fd8a8735953 
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/GrGLProgramStage.h"
17#endif
18
19SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(const SkISize& kernelSize, const SkScalar* kernel, SkScalar gain, SkScalar bias, const SkIPoint& target, TileMode tileMode, bool convolveAlpha, SkImageFilter* input)
20  : INHERITED(input),
21    fKernelSize(kernelSize),
22    fGain(gain),
23    fBias(bias),
24    fTarget(target),
25    fTileMode(tileMode),
26    fConvolveAlpha(convolveAlpha) {
27    uint32_t size = fKernelSize.fWidth * fKernelSize.fHeight;
28    fKernel = SkNEW_ARRAY(SkScalar, size);
29    memcpy(fKernel, kernel, size * sizeof(SkScalar));
30    SkASSERT(kernelSize.fWidth >= 1 && kernelSize.fHeight >= 1);
31    SkASSERT(target.fX >= 0 && target.fX < kernelSize.fWidth);
32    SkASSERT(target.fY >= 0 && target.fY < kernelSize.fHeight);
33}
34
35SkMatrixConvolutionImageFilter::SkMatrixConvolutionImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {
36    fKernelSize.fWidth = buffer.readInt();
37    fKernelSize.fHeight = buffer.readInt();
38    uint32_t size = fKernelSize.fWidth * fKernelSize.fHeight;
39    fKernel = SkNEW_ARRAY(SkScalar, size);
40    uint32_t readSize = buffer.readScalarArray(fKernel);
41    SkASSERT(readSize == size);
42    fGain = buffer.readScalar();
43    fBias = buffer.readScalar();
44    fTarget.fX = buffer.readScalar();
45    fTarget.fY = buffer.readScalar();
46    fTileMode = (TileMode) buffer.readInt();
47    fConvolveAlpha = buffer.readBool();
48}
49
50void SkMatrixConvolutionImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const {
51    this->INHERITED::flatten(buffer);
52    buffer.writeInt(fKernelSize.fWidth);
53    buffer.writeInt(fKernelSize.fHeight);
54    buffer.writeScalarArray(fKernel, fKernelSize.fWidth * fKernelSize.fHeight);
55    buffer.writeScalar(fGain);
56    buffer.writeScalar(fBias);
57    buffer.writeScalar(fTarget.fX);
58    buffer.writeScalar(fTarget.fY);
59    buffer.writeInt((int) fTileMode);
60    buffer.writeBool(fConvolveAlpha);
61}
62
63SkMatrixConvolutionImageFilter::~SkMatrixConvolutionImageFilter() {
64    delete[] fKernel;
65}
66
67class UncheckedPixelFetcher {
68public:
69    static inline SkPMColor fetch(const SkBitmap& src, int x, int y) {
70        return *src.getAddr32(x, y);
71    }
72};
73
74class ClampPixelFetcher {
75public:
76    static inline SkPMColor fetch(const SkBitmap& src, int x, int y) {
77        x = SkClampMax(x, src.width() - 1);
78        y = SkClampMax(y, src.height() - 1);
79        return *src.getAddr32(x, y);
80    }
81};
82
83class RepeatPixelFetcher {
84public:
85    static inline SkPMColor fetch(const SkBitmap& src, int x, int y) {
86        x %= src.width();
87        y %= src.height();
88        if (x < 0) {
89            x += src.width();
90        }
91        if (y < 0) {
92            y += src.height();
93        }
94        return *src.getAddr32(x, y);
95    }
96};
97
98class ClampToBlackPixelFetcher {
99public:
100    static inline SkPMColor fetch(const SkBitmap& src, int x, int y) {
101        if (x < 0 || x >= src.width() || y < 0 || y >= src.height()) {
102            return 0;
103        } else {
104            return *src.getAddr32(x, y);
105        }
106    }
107};
108
109template<class PixelFetcher, bool convolveAlpha>
110void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src, SkBitmap* result, const SkIRect& rect) {
111    for (int y = rect.fTop; y < rect.fBottom; ++y) {
112        SkPMColor* dptr = result->getAddr32(rect.fLeft, y);
113        for (int x = rect.fLeft; x < rect.fRight; ++x) {
114            SkScalar sumA = 0, sumR = 0, sumG = 0, sumB = 0;
115            for (int cy = 0; cy < fKernelSize.fHeight; cy++) {
116                for (int cx = 0; cx < fKernelSize.fWidth; cx++) {
117                    SkPMColor s = PixelFetcher::fetch(src, x + cx - fTarget.fX, y + cy - fTarget.fY);
118                    SkScalar k = fKernel[cy * fKernelSize.fWidth + cx];
119                    if (convolveAlpha) {
120                        sumA += SkScalarMul(SkIntToScalar(SkGetPackedA32(s)), k);
121                    }
122                    sumR += SkScalarMul(SkIntToScalar(SkGetPackedR32(s)), k);
123                    sumG += SkScalarMul(SkIntToScalar(SkGetPackedG32(s)), k);
124                    sumB += SkScalarMul(SkIntToScalar(SkGetPackedB32(s)), k);
125                }
126            }
127            int a = convolveAlpha
128                  ? SkClampMax(SkScalarFloorToInt(SkScalarMul(sumA, fGain) + fBias), 255)
129                  : 255;
130            int r = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumR, fGain) + fBias), a);
131            int g = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumG, fGain) + fBias), a);
132            int b = SkClampMax(SkScalarFloorToInt(SkScalarMul(sumB, fGain) + fBias), a);
133            if (!convolveAlpha) {
134                a = SkGetPackedA32(PixelFetcher::fetch(src, x, y));
135                *dptr++ = SkPreMultiplyARGB(a, r, g, b);
136            } else {
137                *dptr++ = SkPackARGB32(a, r, g, b);
138            }
139        }
140    }
141}
142
143template<class PixelFetcher>
144void SkMatrixConvolutionImageFilter::filterPixels(const SkBitmap& src, SkBitmap* result, const SkIRect& rect) {
145    if (fConvolveAlpha) {
146        filterPixels<PixelFetcher, true>(src, result, rect);
147    } else {
148        filterPixels<PixelFetcher, false>(src, result, rect);
149    }
150}
151
152void SkMatrixConvolutionImageFilter::filterInteriorPixels(const SkBitmap& src, SkBitmap* result, const SkIRect& rect) {
153    filterPixels<UncheckedPixelFetcher>(src, result, rect);
154}
155
156void SkMatrixConvolutionImageFilter::filterBorderPixels(const SkBitmap& src, SkBitmap* result, const SkIRect& rect) {
157    switch (fTileMode) {
158        case kClamp_TileMode:
159            filterPixels<ClampPixelFetcher>(src, result, rect);
160            break;
161        case kRepeat_TileMode:
162            filterPixels<RepeatPixelFetcher>(src, result, rect);
163            break;
164        case kClampToBlack_TileMode:
165            filterPixels<ClampToBlackPixelFetcher>(src, result, rect);
166            break;
167    }
168}
169
170// FIXME:  This should be refactored to SkSingleInputImageFilter for
171// use by other filters.  For now, we assume the input is always
172// premultiplied and unpremultiply it
173static SkBitmap unpremultiplyBitmap(const SkBitmap& src)
174{
175    SkAutoLockPixels alp(src);
176    if (!src.getPixels()) {
177        return SkBitmap();
178    }
179    SkBitmap result;
180    result.setConfig(src.config(), src.width(), src.height());
181    result.allocPixels();
182    if (!result.getPixels()) {
183        return SkBitmap();
184    }
185    for (int y = 0; y < src.height(); ++y) {
186        const uint32_t* srcRow = src.getAddr32(0, y);
187        uint32_t* dstRow = result.getAddr32(0, y);
188        for (int x = 0; x < src.width(); ++x) {
189            dstRow[x] = SkUnPreMultiply::PMColorToColor(srcRow[x]);
190        }
191    }
192    return result;
193}
194
195bool SkMatrixConvolutionImageFilter::onFilterImage(Proxy* proxy,
196                                                   const SkBitmap& source,
197                                                   const SkMatrix& matrix,
198                                                   SkBitmap* result,
199                                                   SkIPoint* loc) {
200    SkBitmap src = this->getInputResult(proxy, source, matrix, loc);
201    if (src.config() != SkBitmap::kARGB_8888_Config) {
202        return false;
203    }
204
205    if (!fConvolveAlpha && !src.isOpaque()) {
206        src = unpremultiplyBitmap(src);
207    }
208
209    SkAutoLockPixels alp(src);
210    if (!src.getPixels()) {
211        return false;
212    }
213
214    result->setConfig(src.config(), src.width(), src.height());
215    result->allocPixels();
216
217    SkIRect interior = SkIRect::MakeXYWH(fTarget.fX, fTarget.fY,
218                                         src.width() - fKernelSize.fWidth + 1,
219                                         src.height() - fKernelSize.fHeight + 1);
220    SkIRect top = SkIRect::MakeWH(src.width(), fTarget.fY);
221    SkIRect bottom = SkIRect::MakeLTRB(0, interior.bottom(),
222                                       src.width(), src.height());
223    SkIRect left = SkIRect::MakeXYWH(0, interior.top(),
224                                     fTarget.fX, interior.height());
225    SkIRect right = SkIRect::MakeLTRB(interior.right(), interior.top(),
226                                      src.width(), interior.bottom());
227    filterBorderPixels(src, result, top);
228    filterBorderPixels(src, result, left);
229    filterInteriorPixels(src, result, interior);
230    filterBorderPixels(src, result, right);
231    filterBorderPixels(src, result, bottom);
232    return true;
233}
234
235#if SK_SUPPORT_GPU
236
237///////////////////////////////////////////////////////////////////////////////
238
239class GrGLMatrixConvolutionEffect;
240
241class GrMatrixConvolutionEffect : public GrSingleTextureEffect {
242public:
243    typedef SkMatrixConvolutionImageFilter::TileMode TileMode;
244    GrMatrixConvolutionEffect(GrTexture*,
245                              const SkISize& kernelSize,
246                              const SkScalar* kernel,
247                              SkScalar gain,
248                              SkScalar bias,
249                              const SkIPoint& target,
250                              TileMode tileMode,
251                              bool convolveAlpha);
252    virtual ~GrMatrixConvolutionEffect();
253
254    static const char* Name() { return "MatrixConvolution"; }
255    const SkISize& kernelSize() const { return fKernelSize; }
256    const float* target() const { return fTarget; }
257    const float* kernel() const { return fKernel; }
258    float gain() const { return fGain; }
259    float bias() const { return fBias; }
260    TileMode tileMode() const { return fTileMode; }
261    bool convolveAlpha() const { return fConvolveAlpha; }
262
263    typedef GrGLMatrixConvolutionEffect GLProgramStage;
264
265    virtual const GrProgramStageFactory& getFactory() const SK_OVERRIDE;
266    virtual bool isEqual(const GrCustomStage&) const SK_OVERRIDE;
267
268private:
269    SkISize  fKernelSize;
270    float   *fKernel;
271    float    fGain;
272    float    fBias;
273    float    fTarget[2];
274    TileMode fTileMode;
275    bool     fConvolveAlpha;
276
277    GR_DECLARE_CUSTOM_STAGE_TEST;
278
279    typedef GrSingleTextureEffect INHERITED;
280};
281
282class GrGLMatrixConvolutionEffect : public GrGLProgramStage {
283public:
284    GrGLMatrixConvolutionEffect(const GrProgramStageFactory& factory,
285                                const GrCustomStage& stage);
286    virtual void setupVariables(GrGLShaderBuilder* builder) SK_OVERRIDE;
287    virtual void emitVS(GrGLShaderBuilder* state,
288                        const char* vertexCoords) SK_OVERRIDE {}
289    virtual void emitFS(GrGLShaderBuilder* state,
290                        const char* outputColor,
291                        const char* inputColor,
292                        const TextureSamplerArray&) SK_OVERRIDE;
293
294    static inline StageKey GenKey(const GrCustomStage& s, const GrGLCaps& caps);
295
296    virtual void setData(const GrGLUniformManager&, const GrCustomStage&) SK_OVERRIDE;
297
298private:
299    typedef GrGLUniformManager::UniformHandle        UniformHandle;
300    typedef SkMatrixConvolutionImageFilter::TileMode TileMode;
301    SkISize        fKernelSize;
302    TileMode       fTileMode;
303    bool           fConvolveAlpha;
304
305    UniformHandle  fKernelUni;
306    UniformHandle  fImageIncrementUni;
307    UniformHandle  fTargetUni;
308    UniformHandle  fGainUni;
309    UniformHandle  fBiasUni;
310};
311
312GrGLMatrixConvolutionEffect::GrGLMatrixConvolutionEffect(const GrProgramStageFactory& factory,
313                                           const GrCustomStage& stage)
314    : GrGLProgramStage(factory)
315    , fKernelUni(GrGLUniformManager::kInvalidUniformHandle)
316    , fImageIncrementUni(GrGLUniformManager::kInvalidUniformHandle)
317    , fTargetUni(GrGLUniformManager::kInvalidUniformHandle)
318    , fGainUni(GrGLUniformManager::kInvalidUniformHandle)
319    , fBiasUni(GrGLUniformManager::kInvalidUniformHandle) {
320    const GrMatrixConvolutionEffect& m = static_cast<const GrMatrixConvolutionEffect&>(stage);
321    fKernelSize = m.kernelSize();
322    fTileMode = m.tileMode();
323    fConvolveAlpha = m.convolveAlpha();
324}
325
326void GrGLMatrixConvolutionEffect::setupVariables(GrGLShaderBuilder* builder) {
327    fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType,
328                                             kVec2f_GrSLType, "ImageIncrement");
329    fKernelUni = builder->addUniformArray(GrGLShaderBuilder::kFragment_ShaderType,
330                                             kFloat_GrSLType, "Kernel", fKernelSize.width() * fKernelSize.height());
331    fTargetUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType,
332                                             kVec2f_GrSLType, "Target");
333    fGainUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType,
334                                   kFloat_GrSLType, "Gain");
335    fBiasUni = builder->addUniform(GrGLShaderBuilder::kFragment_ShaderType,
336                                   kFloat_GrSLType, "Bias");
337}
338
339static void appendTextureLookup(GrGLShaderBuilder* builder,
340                                const GrGLShaderBuilder::TextureSampler& sampler,
341                                const char* coord,
342                                SkMatrixConvolutionImageFilter::TileMode tileMode) {
343    SkString* code = &builder->fFSCode;
344    SkString clampedCoord;
345    switch (tileMode) {
346        case SkMatrixConvolutionImageFilter::kClamp_TileMode:
347            clampedCoord.printf("clamp(%s, 0.0, 1.0)", coord);
348            coord = clampedCoord.c_str();
349            break;
350        case SkMatrixConvolutionImageFilter::kRepeat_TileMode:
351            clampedCoord.printf("fract(%s)", coord);
352            coord = clampedCoord.c_str();
353            break;
354        case SkMatrixConvolutionImageFilter::kClampToBlack_TileMode:
355            code->appendf("clamp(%s, 0.0, 1.0) != %s ? vec4(0, 0, 0, 0) : ", coord, coord);
356            break;
357    }
358    builder->appendTextureLookup(code, sampler, coord);
359}
360
361void GrGLMatrixConvolutionEffect::emitFS(GrGLShaderBuilder* builder,
362                                  const char* outputColor,
363                                  const char* inputColor,
364                                  const TextureSamplerArray& samplers) {
365    SkString* code = &builder->fFSCode;
366
367    const char* target = builder->getUniformCStr(fTargetUni);
368    const char* imgInc = builder->getUniformCStr(fImageIncrementUni);
369    const char* kernel = builder->getUniformCStr(fKernelUni);
370    const char* gain = builder->getUniformCStr(fGainUni);
371    const char* bias = builder->getUniformCStr(fBiasUni);
372    int kWidth = fKernelSize.width();
373    int kHeight = fKernelSize.height();
374
375    code->appendf("\t\tvec4 sum = vec4(0, 0, 0, 0);\n");
376    code->appendf("\t\tvec2 coord = %s - %s * %s;\n",
377                  builder->defaultTexCoordsName(), target, imgInc);
378    code->appendf("\t\tfor (int y = 0; y < %d; y++) {\n", kHeight);
379    code->appendf("\t\t\tfor (int x = 0; x < %d; x++) {\n", kWidth);
380    code->appendf("\t\t\t\tfloat k = %s[y * %d + x];\n", kernel, kWidth);
381    code->appendf("\t\t\t\tvec2 coord2 = coord + vec2(x, y) * %s;\n", imgInc);
382    code->appendf("\t\t\t\tvec4 c = ");
383    appendTextureLookup(builder, samplers[0], "coord2", fTileMode);
384    code->appendf(";\n");
385    if (!fConvolveAlpha) {
386        code->appendf("\t\t\t\tc.rgb /= c.a;\n");
387    }
388    code->appendf("\t\t\t\tsum += c * k;\n");
389    code->appendf("\t\t\t}\n");
390    code->appendf("\t\t}\n");
391    if (fConvolveAlpha) {
392        code->appendf("\t\t%s = sum * %s + %s;\n", outputColor, gain, bias);
393        code->appendf("\t\t%s.rgb = clamp(%s.rgb, 0.0, %s.a);\n", outputColor, outputColor, outputColor);
394    } else {
395        code->appendf("\t\tvec4 c = ");
396        appendTextureLookup(builder, samplers[0], builder->defaultTexCoordsName(), fTileMode);
397        code->appendf(";\n");
398        code->appendf("\t\t%s.a = c.a;\n", outputColor);
399        code->appendf("\t\t%s.rgb = sum.rgb * %s + %s;\n", outputColor, gain, bias);
400        code->appendf("\t\t%s.rgb *= %s.a;\n", outputColor, outputColor);
401    }
402}
403
404namespace {
405
406int encodeXY(int x, int y) {
407    SkASSERT(x >= 1 && y >= 1 && x * y <= 32);
408    if (y < x)
409        return 0x40 | encodeXY(y, x);
410    else
411        return (0x40 >> x) | (y - x);
412}
413
414};
415
416GrGLProgramStage::StageKey GrGLMatrixConvolutionEffect::GenKey(const GrCustomStage& s,
417                                                        const GrGLCaps& caps) {
418    const GrMatrixConvolutionEffect& m = static_cast<const GrMatrixConvolutionEffect&>(s);
419    StageKey key = encodeXY(m.kernelSize().width(), m.kernelSize().height());
420    key |= m.tileMode() << 7;
421    key |= m.convolveAlpha() ? 1 << 9 : 0;
422    return key;
423}
424
425void GrGLMatrixConvolutionEffect::setData(const GrGLUniformManager& uman,
426                                          const GrCustomStage& data) {
427    const GrMatrixConvolutionEffect& effect =
428        static_cast<const GrMatrixConvolutionEffect&>(data);
429    GrGLTexture& texture =
430        *static_cast<GrGLTexture*>(data.texture(0));
431    // the code we generated was for a specific kernel size
432    GrAssert(effect.kernelSize() == fKernelSize);
433    GrAssert(effect.tileMode() == fTileMode);
434    float imageIncrement[2];
435    imageIncrement[0] = 1.0f / texture.width();
436    imageIncrement[1] = 1.0f / texture.height();
437    uman.set2fv(fImageIncrementUni, 0, 1, imageIncrement);
438    uman.set2fv(fTargetUni, 0, 1, effect.target());
439    uman.set1fv(fKernelUni, 0, fKernelSize.width() * fKernelSize.height(), effect.kernel());
440    uman.set1f(fGainUni, effect.gain());
441    uman.set1f(fBiasUni, effect.bias());
442}
443
444GrMatrixConvolutionEffect::GrMatrixConvolutionEffect(GrTexture* texture,
445                                                     const SkISize& kernelSize,
446                                                     const SkScalar* kernel,
447                                                     SkScalar gain,
448                                                     SkScalar bias,
449                                                     const SkIPoint& target,
450                                                     TileMode tileMode,
451                                                     bool convolveAlpha)
452  : INHERITED(texture),
453    fKernelSize(kernelSize),
454    fGain(SkScalarToFloat(gain)),
455    fBias(SkScalarToFloat(bias) / 255.0f),
456    fTileMode(tileMode),
457    fConvolveAlpha(convolveAlpha) {
458    fKernel = new float[kernelSize.width() * kernelSize.height()];
459    for (int i = 0; i < kernelSize.width() * kernelSize.height(); i++) {
460        fKernel[i] = SkScalarToFloat(kernel[i]);
461    }
462    fTarget[0] = target.x();
463    fTarget[1] = target.y();
464}
465
466GrMatrixConvolutionEffect::~GrMatrixConvolutionEffect() {
467    delete[] fKernel;
468}
469
470const GrProgramStageFactory& GrMatrixConvolutionEffect::getFactory() const {
471    return GrTProgramStageFactory<GrMatrixConvolutionEffect>::getInstance();
472}
473
474bool GrMatrixConvolutionEffect::isEqual(const GrCustomStage& sBase) const {
475    const GrMatrixConvolutionEffect& s =
476        static_cast<const GrMatrixConvolutionEffect&>(sBase);
477    return INHERITED::isEqual(sBase) &&
478           fKernelSize == s.kernelSize() &&
479           !memcmp(fKernel, s.kernel(), fKernelSize.width() * fKernelSize.height() * sizeof(float)) &&
480           fGain == s.gain() &&
481           fBias == s.bias() &&
482           fTarget == s.target() &&
483           fTileMode == s.tileMode() &&
484           fConvolveAlpha == s.convolveAlpha();
485}
486
487GR_DEFINE_CUSTOM_STAGE_TEST(GrMatrixConvolutionEffect);
488
489// A little bit less than the minimum # uniforms required by DX9SM2 (32).
490// Allows for a 5x5 kernel (or 25x1, for that matter).
491#define MAX_KERNEL_SIZE 25
492
493GrCustomStage* GrMatrixConvolutionEffect::TestCreate(SkRandom* random,
494                                                     GrContext* context,
495                                                     GrTexture* textures[]) {
496    int texIdx = random->nextBool() ? GrCustomStageUnitTest::kSkiaPMTextureIdx :
497                                      GrCustomStageUnitTest::kAlphaTextureIdx;
498    int width = random->nextRangeU(1, MAX_KERNEL_SIZE);
499    int height = random->nextRangeU(1, MAX_KERNEL_SIZE / width);
500    SkISize kernelSize = SkISize::Make(width, height);
501    SkScalar* kernel = new SkScalar[width * height];
502    for (int i = 0; i < width * height; i++) {
503        kernel[i] = random->nextSScalar1();
504    }
505    SkScalar gain = random->nextSScalar1();
506    SkScalar bias = random->nextSScalar1();
507    SkIPoint target = SkIPoint::Make(random->nextRangeU(0, kernelSize.width()),
508                                     random->nextRangeU(0, kernelSize.height()));
509    TileMode tileMode = static_cast<TileMode>(random->nextRangeU(0, 2));
510    bool convolveAlpha = random->nextBool();
511    return SkNEW_ARGS(GrMatrixConvolutionEffect, (textures[texIdx],
512                                                  kernelSize,
513                                                  kernel,
514                                                  gain,
515                                                  bias,
516                                                  target,
517                                                  tileMode,
518                                                  convolveAlpha));
519
520}
521
522bool SkMatrixConvolutionImageFilter::asNewCustomStage(GrCustomStage** stage,
523                                                      GrTexture* texture) const {
524    bool ok = fKernelSize.width() * fKernelSize.height() <= MAX_KERNEL_SIZE;
525    if (ok && stage) {
526        *stage = SkNEW_ARGS(GrMatrixConvolutionEffect, (texture,
527                                                        fKernelSize,
528                                                        fKernel,
529                                                        fGain,
530                                                        fBias,
531                                                        fTarget,
532                                                        fTileMode,
533                                                        fConvolveAlpha));
534    }
535    return ok;
536}
537
538///////////////////////////////////////////////////////////////////////////////
539
540#endif
541