| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkLinearGradient.h" |
| |
| static const float kInv255Float = 1.0f / 255; |
| |
| static inline int repeat_bits(int x, const int bits) { |
| return x & ((1 << bits) - 1); |
| } |
| |
| static inline int repeat_8bits(int x) { |
| return x & 0xFF; |
| } |
| |
| // Visual Studio 2010 (MSC_VER=1600) optimizes bit-shift code incorrectly. |
| // See http://code.google.com/p/skia/issues/detail?id=472 |
| #if defined(_MSC_VER) && (_MSC_VER >= 1600) |
| #pragma optimize("", off) |
| #endif |
| |
| static inline int mirror_bits(int x, const int bits) { |
| if (x & (1 << bits)) { |
| x = ~x; |
| } |
| return x & ((1 << bits) - 1); |
| } |
| |
| static inline int mirror_8bits(int x) { |
| if (x & 256) { |
| x = ~x; |
| } |
| return x & 255; |
| } |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1600) |
| #pragma optimize("", on) |
| #endif |
| |
| static SkMatrix pts_to_unit_matrix(const SkPoint pts[2]) { |
| SkVector vec = pts[1] - pts[0]; |
| SkScalar mag = vec.length(); |
| SkScalar inv = mag ? SkScalarInvert(mag) : 0; |
| |
| vec.scale(inv); |
| SkMatrix matrix; |
| matrix.setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY); |
| matrix.postTranslate(-pts[0].fX, -pts[0].fY); |
| matrix.postScale(inv, inv); |
| return matrix; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| SkLinearGradient::SkLinearGradient(const SkPoint pts[2], const Descriptor& desc) |
| : SkGradientShaderBase(desc, pts_to_unit_matrix(pts)) |
| , fStart(pts[0]) |
| , fEnd(pts[1]) { |
| } |
| |
| SkFlattenable* SkLinearGradient::CreateProc(SkReadBuffer& buffer) { |
| DescriptorScope desc; |
| if (!desc.unflatten(buffer)) { |
| return nullptr; |
| } |
| SkPoint pts[2]; |
| pts[0] = buffer.readPoint(); |
| pts[1] = buffer.readPoint(); |
| return SkGradientShader::CreateLinear(pts, desc.fColors, desc.fPos, desc.fCount, |
| desc.fTileMode, desc.fGradFlags, desc.fLocalMatrix); |
| } |
| |
| void SkLinearGradient::flatten(SkWriteBuffer& buffer) const { |
| this->INHERITED::flatten(buffer); |
| buffer.writePoint(fStart); |
| buffer.writePoint(fEnd); |
| } |
| |
| size_t SkLinearGradient::contextSize() const { |
| return sizeof(LinearGradientContext); |
| } |
| |
| SkShader::Context* SkLinearGradient::onCreateContext(const ContextRec& rec, void* storage) const { |
| return new (storage) LinearGradientContext(*this, rec); |
| } |
| |
| // This swizzles SkColor into the same component order as SkPMColor, but does not actually |
| // "pre" multiply the color components. |
| // |
| // This allows us to map directly to Sk4f, and eventually scale down to bytes to output a |
| // SkPMColor from the floats, without having to swizzle each time. |
| // |
| static uint32_t SkSwizzle_Color_to_PMColor(SkColor c) { |
| return SkPackARGB32NoCheck(SkColorGetA(c), SkColorGetR(c), SkColorGetG(c), SkColorGetB(c)); |
| } |
| |
| SkLinearGradient::LinearGradientContext::LinearGradientContext( |
| const SkLinearGradient& shader, const ContextRec& ctx) |
| : INHERITED(shader, ctx) |
| { |
| unsigned mask = SkMatrix::kTranslate_Mask | SkMatrix::kScale_Mask; |
| if ((fDstToIndex.getType() & ~mask) == 0) { |
| // when we dither, we are (usually) not const-in-Y |
| if ((fFlags & SkShader::kHasSpan16_Flag) && !ctx.fPaint->isDither()) { |
| // only claim this if we do have a 16bit mode (i.e. none of our |
| // colors have alpha), and if we are not dithering (which obviously |
| // is not const in Y). |
| fFlags |= SkShader::kConstInY16_Flag; |
| } |
| } |
| |
| // setup for Sk4f |
| int count = shader.fColorCount; |
| fRecs.setCount(count); |
| Rec* rec = fRecs.begin(); |
| if (shader.fOrigPos) { |
| rec[0].fPos = 0; |
| SkDEBUGCODE(rec[0].fPosScale = SK_FloatNaN;) // should never get used |
| for (int i = 1; i < count; ++i) { |
| rec[i].fPos = SkTPin(shader.fOrigPos[i], rec[i - 1].fPos, 1.0f); |
| rec[i].fPosScale = 1.0f / (rec[i].fPos - rec[i - 1].fPos); |
| } |
| rec[count - 1].fPos = 1; // overwrite the last value just to be sure we end at 1.0 |
| } else { |
| // no pos specified, so we compute evenly spaced values |
| const float scale = float(count - 1); |
| float invScale = 1.0f / scale; |
| for (int i = 0; i < count; ++i) { |
| rec[i].fPos = i * invScale; |
| rec[i].fPosScale = scale; |
| } |
| } |
| |
| fApplyAlphaAfterInterp = true; |
| if ((shader.getGradFlags() & SkGradientShader::kInterpolateColorsInPremul_Flag) || |
| shader.colorsAreOpaque()) |
| { |
| fApplyAlphaAfterInterp = false; |
| } |
| |
| if (fApplyAlphaAfterInterp) { |
| // Our fColor values are in PMColor order, but are still unpremultiplied, allowing us to |
| // interpolate in unpremultiplied space first, and then scale by alpha right before we |
| // convert to SkPMColor bytes. |
| const float paintAlpha = ctx.fPaint->getAlpha() * kInv255Float; |
| const Sk4f scale(1, 1, 1, paintAlpha); |
| for (int i = 0; i < count; ++i) { |
| uint32_t c = SkSwizzle_Color_to_PMColor(shader.fOrigColors[i]); |
| rec[i].fColor = Sk4f::FromBytes((const uint8_t*)&c) * scale; |
| if (i > 0) { |
| SkASSERT(rec[i - 1].fPos <= rec[i].fPos); |
| } |
| } |
| } else { |
| // Our fColor values are premultiplied, so converting to SkPMColor is just a matter |
| // of converting the floats down to bytes. |
| unsigned alphaScale = ctx.fPaint->getAlpha() + (ctx.fPaint->getAlpha() >> 7); |
| for (int i = 0; i < count; ++i) { |
| SkPMColor pmc = SkPreMultiplyColor(shader.fOrigColors[i]); |
| pmc = SkAlphaMulQ(pmc, alphaScale); |
| rec[i].fColor = Sk4f::FromBytes((const uint8_t*)&pmc); |
| if (i > 0) { |
| SkASSERT(rec[i - 1].fPos <= rec[i].fPos); |
| } |
| } |
| } |
| } |
| |
| #define NO_CHECK_ITER \ |
| do { \ |
| unsigned fi = SkGradFixedToFixed(fx) >> SkGradientShaderBase::kCache32Shift; \ |
| SkASSERT(fi <= 0xFF); \ |
| fx += dx; \ |
| *dstC++ = cache[toggle + fi]; \ |
| toggle = next_dither_toggle(toggle); \ |
| } while (0) |
| |
| namespace { |
| |
| typedef void (*LinearShadeProc)(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| SkPMColor* dstC, const SkPMColor* cache, |
| int toggle, int count); |
| |
| // Linear interpolation (lerp) is unnecessary if there are no sharp |
| // discontinuities in the gradient - which must be true if there are |
| // only 2 colors - but it's cheap. |
| void shadeSpan_linear_vertical_lerp(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| SkPMColor* SK_RESTRICT dstC, |
| const SkPMColor* SK_RESTRICT cache, |
| int toggle, int count) { |
| // We're a vertical gradient, so no change in a span. |
| // If colors change sharply across the gradient, dithering is |
| // insufficient (it subsamples the color space) and we need to lerp. |
| unsigned fullIndex = proc(SkGradFixedToFixed(fx)); |
| unsigned fi = fullIndex >> SkGradientShaderBase::kCache32Shift; |
| unsigned remainder = fullIndex & ((1 << SkGradientShaderBase::kCache32Shift) - 1); |
| |
| int index0 = fi + toggle; |
| int index1 = index0; |
| if (fi < SkGradientShaderBase::kCache32Count - 1) { |
| index1 += 1; |
| } |
| SkPMColor lerp = SkFastFourByteInterp(cache[index1], cache[index0], remainder); |
| index0 ^= SkGradientShaderBase::kDitherStride32; |
| index1 ^= SkGradientShaderBase::kDitherStride32; |
| SkPMColor dlerp = SkFastFourByteInterp(cache[index1], cache[index0], remainder); |
| sk_memset32_dither(dstC, lerp, dlerp, count); |
| } |
| |
| void shadeSpan_linear_clamp(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| SkPMColor* SK_RESTRICT dstC, |
| const SkPMColor* SK_RESTRICT cache, |
| int toggle, int count) { |
| SkClampRange range; |
| range.init(fx, dx, count, 0, SkGradientShaderBase::kCache32Count - 1); |
| range.validate(count); |
| |
| if ((count = range.fCount0) > 0) { |
| sk_memset32_dither(dstC, |
| cache[toggle + range.fV0], |
| cache[next_dither_toggle(toggle) + range.fV0], |
| count); |
| dstC += count; |
| } |
| if ((count = range.fCount1) > 0) { |
| int unroll = count >> 3; |
| fx = range.fFx1; |
| for (int i = 0; i < unroll; i++) { |
| NO_CHECK_ITER; NO_CHECK_ITER; |
| NO_CHECK_ITER; NO_CHECK_ITER; |
| NO_CHECK_ITER; NO_CHECK_ITER; |
| NO_CHECK_ITER; NO_CHECK_ITER; |
| } |
| if ((count &= 7) > 0) { |
| do { |
| NO_CHECK_ITER; |
| } while (--count != 0); |
| } |
| } |
| if ((count = range.fCount2) > 0) { |
| sk_memset32_dither(dstC, |
| cache[toggle + range.fV1], |
| cache[next_dither_toggle(toggle) + range.fV1], |
| count); |
| } |
| } |
| |
| void shadeSpan_linear_mirror(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| SkPMColor* SK_RESTRICT dstC, |
| const SkPMColor* SK_RESTRICT cache, |
| int toggle, int count) { |
| do { |
| unsigned fi = mirror_8bits(SkGradFixedToFixed(fx) >> 8); |
| SkASSERT(fi <= 0xFF); |
| fx += dx; |
| *dstC++ = cache[toggle + fi]; |
| toggle = next_dither_toggle(toggle); |
| } while (--count != 0); |
| } |
| |
| void shadeSpan_linear_repeat(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| SkPMColor* SK_RESTRICT dstC, |
| const SkPMColor* SK_RESTRICT cache, |
| int toggle, int count) { |
| do { |
| unsigned fi = repeat_8bits(SkGradFixedToFixed(fx) >> 8); |
| SkASSERT(fi <= 0xFF); |
| fx += dx; |
| *dstC++ = cache[toggle + fi]; |
| toggle = next_dither_toggle(toggle); |
| } while (--count != 0); |
| } |
| |
| } |
| |
| void SkLinearGradient::LinearGradientContext::shadeSpan(int x, int y, SkPMColor* SK_RESTRICT dstC, |
| int count) { |
| SkASSERT(count > 0); |
| const SkLinearGradient& linearGradient = static_cast<const SkLinearGradient&>(fShader); |
| |
| #ifndef SK_SUPPORT_LEGACY_LINEAR_GRADIENT_TABLE |
| if (SkShader::kClamp_TileMode == linearGradient.fTileMode && |
| kLinear_MatrixClass == fDstToIndexClass) |
| { |
| this->shade4_clamp(x, y, dstC, count); |
| return; |
| } |
| #endif |
| |
| SkPoint srcPt; |
| SkMatrix::MapXYProc dstProc = fDstToIndexProc; |
| TileProc proc = linearGradient.fTileProc; |
| const SkPMColor* SK_RESTRICT cache = fCache->getCache32(); |
| int toggle = init_dither_toggle(x, y); |
| |
| if (fDstToIndexClass != kPerspective_MatrixClass) { |
| dstProc(fDstToIndex, SkIntToScalar(x) + SK_ScalarHalf, |
| SkIntToScalar(y) + SK_ScalarHalf, &srcPt); |
| SkGradFixed dx, fx = SkScalarToGradFixed(srcPt.fX); |
| |
| if (fDstToIndexClass == kFixedStepInX_MatrixClass) { |
| SkFixed dxStorage[1]; |
| (void)fDstToIndex.fixedStepInX(SkIntToScalar(y), dxStorage, nullptr); |
| // todo: do we need a real/high-precision value for dx here? |
| dx = SkFixedToGradFixed(dxStorage[0]); |
| } else { |
| SkASSERT(fDstToIndexClass == kLinear_MatrixClass); |
| dx = SkScalarToGradFixed(fDstToIndex.getScaleX()); |
| } |
| |
| LinearShadeProc shadeProc = shadeSpan_linear_repeat; |
| if (0 == dx) { |
| shadeProc = shadeSpan_linear_vertical_lerp; |
| } else if (SkShader::kClamp_TileMode == linearGradient.fTileMode) { |
| shadeProc = shadeSpan_linear_clamp; |
| } else if (SkShader::kMirror_TileMode == linearGradient.fTileMode) { |
| shadeProc = shadeSpan_linear_mirror; |
| } else { |
| SkASSERT(SkShader::kRepeat_TileMode == linearGradient.fTileMode); |
| } |
| (*shadeProc)(proc, dx, fx, dstC, cache, toggle, count); |
| } else { |
| SkScalar dstX = SkIntToScalar(x); |
| SkScalar dstY = SkIntToScalar(y); |
| do { |
| dstProc(fDstToIndex, dstX, dstY, &srcPt); |
| unsigned fi = proc(SkScalarToFixed(srcPt.fX)); |
| SkASSERT(fi <= 0xFFFF); |
| *dstC++ = cache[toggle + (fi >> kCache32Shift)]; |
| toggle = next_dither_toggle(toggle); |
| dstX += SK_Scalar1; |
| } while (--count != 0); |
| } |
| } |
| |
| SkShader::GradientType SkLinearGradient::asAGradient(GradientInfo* info) const { |
| if (info) { |
| commonAsAGradient(info); |
| info->fPoint[0] = fStart; |
| info->fPoint[1] = fEnd; |
| } |
| return kLinear_GradientType; |
| } |
| |
| static void dither_memset16(uint16_t dst[], uint16_t value, uint16_t other, |
| int count) { |
| if (reinterpret_cast<uintptr_t>(dst) & 2) { |
| *dst++ = value; |
| count -= 1; |
| SkTSwap(value, other); |
| } |
| |
| sk_memset32((uint32_t*)dst, (value << 16) | other, count >> 1); |
| |
| if (count & 1) { |
| dst[count - 1] = value; |
| } |
| } |
| |
| #define NO_CHECK_ITER_16 \ |
| do { \ |
| unsigned fi = SkGradFixedToFixed(fx) >> SkGradientShaderBase::kCache16Shift; \ |
| SkASSERT(fi < SkGradientShaderBase::kCache16Count); \ |
| fx += dx; \ |
| *dstC++ = cache[toggle + fi]; \ |
| toggle = next_dither_toggle16(toggle); \ |
| } while (0) |
| |
| namespace { |
| |
| typedef void (*LinearShade16Proc)(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| uint16_t* dstC, const uint16_t* cache, |
| int toggle, int count); |
| |
| void shadeSpan16_linear_vertical(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| uint16_t* SK_RESTRICT dstC, |
| const uint16_t* SK_RESTRICT cache, |
| int toggle, int count) { |
| // we're a vertical gradient, so no change in a span |
| unsigned fi = proc(SkGradFixedToFixed(fx)) >> SkGradientShaderBase::kCache16Shift; |
| SkASSERT(fi < SkGradientShaderBase::kCache16Count); |
| dither_memset16(dstC, cache[toggle + fi], |
| cache[next_dither_toggle16(toggle) + fi], count); |
| } |
| |
| void shadeSpan16_linear_clamp(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| uint16_t* SK_RESTRICT dstC, |
| const uint16_t* SK_RESTRICT cache, |
| int toggle, int count) { |
| SkClampRange range; |
| range.init(fx, dx, count, 0, SkGradientShaderBase::kCache32Count - 1); |
| range.validate(count); |
| |
| if ((count = range.fCount0) > 0) { |
| dither_memset16(dstC, |
| cache[toggle + range.fV0], |
| cache[next_dither_toggle16(toggle) + range.fV0], |
| count); |
| dstC += count; |
| } |
| if ((count = range.fCount1) > 0) { |
| int unroll = count >> 3; |
| fx = range.fFx1; |
| for (int i = 0; i < unroll; i++) { |
| NO_CHECK_ITER_16; NO_CHECK_ITER_16; |
| NO_CHECK_ITER_16; NO_CHECK_ITER_16; |
| NO_CHECK_ITER_16; NO_CHECK_ITER_16; |
| NO_CHECK_ITER_16; NO_CHECK_ITER_16; |
| } |
| if ((count &= 7) > 0) { |
| do { |
| NO_CHECK_ITER_16; |
| } while (--count != 0); |
| } |
| } |
| if ((count = range.fCount2) > 0) { |
| dither_memset16(dstC, |
| cache[toggle + range.fV1], |
| cache[next_dither_toggle16(toggle) + range.fV1], |
| count); |
| } |
| } |
| |
| void shadeSpan16_linear_mirror(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| uint16_t* SK_RESTRICT dstC, |
| const uint16_t* SK_RESTRICT cache, |
| int toggle, int count) { |
| do { |
| unsigned fi = mirror_bits(SkGradFixedToFixed(fx) >> SkGradientShaderBase::kCache16Shift, |
| SkGradientShaderBase::kCache16Bits); |
| SkASSERT(fi < SkGradientShaderBase::kCache16Count); |
| fx += dx; |
| *dstC++ = cache[toggle + fi]; |
| toggle = next_dither_toggle16(toggle); |
| } while (--count != 0); |
| } |
| |
| void shadeSpan16_linear_repeat(TileProc proc, SkGradFixed dx, SkGradFixed fx, |
| uint16_t* SK_RESTRICT dstC, |
| const uint16_t* SK_RESTRICT cache, |
| int toggle, int count) { |
| do { |
| unsigned fi = repeat_bits(SkGradFixedToFixed(fx) >> SkGradientShaderBase::kCache16Shift, |
| SkGradientShaderBase::kCache16Bits); |
| SkASSERT(fi < SkGradientShaderBase::kCache16Count); |
| fx += dx; |
| *dstC++ = cache[toggle + fi]; |
| toggle = next_dither_toggle16(toggle); |
| } while (--count != 0); |
| } |
| } |
| |
| static bool fixed_nearly_zero(SkFixed x) { |
| return SkAbs32(x) < (SK_Fixed1 >> 12); |
| } |
| |
| void SkLinearGradient::LinearGradientContext::shadeSpan16(int x, int y, |
| uint16_t* SK_RESTRICT dstC, int count) { |
| SkASSERT(count > 0); |
| |
| const SkLinearGradient& linearGradient = static_cast<const SkLinearGradient&>(fShader); |
| |
| SkPoint srcPt; |
| SkMatrix::MapXYProc dstProc = fDstToIndexProc; |
| TileProc proc = linearGradient.fTileProc; |
| const uint16_t* SK_RESTRICT cache = fCache->getCache16(); |
| int toggle = init_dither_toggle16(x, y); |
| |
| if (fDstToIndexClass != kPerspective_MatrixClass) { |
| dstProc(fDstToIndex, SkIntToScalar(x) + SK_ScalarHalf, |
| SkIntToScalar(y) + SK_ScalarHalf, &srcPt); |
| SkGradFixed dx, fx = SkScalarToGradFixed(srcPt.fX); |
| |
| if (fDstToIndexClass == kFixedStepInX_MatrixClass) { |
| SkFixed dxStorage[1]; |
| (void)fDstToIndex.fixedStepInX(SkIntToScalar(y), dxStorage, nullptr); |
| // todo: do we need a real/high-precision value for dx here? |
| dx = SkFixedToGradFixed(dxStorage[0]); |
| } else { |
| SkASSERT(fDstToIndexClass == kLinear_MatrixClass); |
| dx = SkScalarToGradFixed(fDstToIndex.getScaleX()); |
| } |
| |
| LinearShade16Proc shadeProc = shadeSpan16_linear_repeat; |
| if (fixed_nearly_zero(SkGradFixedToFixed(dx))) { |
| shadeProc = shadeSpan16_linear_vertical; |
| } else if (SkShader::kClamp_TileMode == linearGradient.fTileMode) { |
| shadeProc = shadeSpan16_linear_clamp; |
| } else if (SkShader::kMirror_TileMode == linearGradient.fTileMode) { |
| shadeProc = shadeSpan16_linear_mirror; |
| } else { |
| SkASSERT(SkShader::kRepeat_TileMode == linearGradient.fTileMode); |
| } |
| (*shadeProc)(proc, dx, fx, dstC, cache, toggle, count); |
| } else { |
| SkScalar dstX = SkIntToScalar(x); |
| SkScalar dstY = SkIntToScalar(y); |
| do { |
| dstProc(fDstToIndex, dstX, dstY, &srcPt); |
| unsigned fi = proc(SkScalarToFixed(srcPt.fX)); |
| SkASSERT(fi <= 0xFFFF); |
| |
| int index = fi >> kCache16Shift; |
| *dstC++ = cache[toggle + index]; |
| toggle = next_dither_toggle16(toggle); |
| |
| dstX += SK_Scalar1; |
| } while (--count != 0); |
| } |
| } |
| |
| #if SK_SUPPORT_GPU |
| |
| #include "gl/builders/GrGLProgramBuilder.h" |
| #include "SkGr.h" |
| |
| ///////////////////////////////////////////////////////////////////// |
| |
| class GrGLLinearGradient : public GrGLGradientEffect { |
| public: |
| |
| GrGLLinearGradient(const GrProcessor&) {} |
| |
| virtual ~GrGLLinearGradient() { } |
| |
| virtual void emitCode(EmitArgs&) override; |
| |
| static void GenKey(const GrProcessor& processor, const GrGLSLCaps&, GrProcessorKeyBuilder* b) { |
| b->add32(GenBaseGradientKey(processor)); |
| } |
| |
| private: |
| |
| typedef GrGLGradientEffect INHERITED; |
| }; |
| |
| ///////////////////////////////////////////////////////////////////// |
| |
| class GrLinearGradient : public GrGradientEffect { |
| public: |
| |
| static GrFragmentProcessor* Create(GrContext* ctx, |
| const SkLinearGradient& shader, |
| const SkMatrix& matrix, |
| SkShader::TileMode tm) { |
| return new GrLinearGradient(ctx, shader, matrix, tm); |
| } |
| |
| virtual ~GrLinearGradient() { } |
| |
| const char* name() const override { return "Linear Gradient"; } |
| |
| private: |
| GrLinearGradient(GrContext* ctx, |
| const SkLinearGradient& shader, |
| const SkMatrix& matrix, |
| SkShader::TileMode tm) |
| : INHERITED(ctx, shader, matrix, tm) { |
| this->initClassID<GrLinearGradient>(); |
| } |
| |
| GrGLSLFragmentProcessor* onCreateGLSLInstance() const override { |
| return new GrGLLinearGradient(*this); |
| } |
| |
| virtual void onGetGLSLProcessorKey(const GrGLSLCaps& caps, |
| GrProcessorKeyBuilder* b) const override { |
| GrGLLinearGradient::GenKey(*this, caps, b); |
| } |
| |
| GR_DECLARE_FRAGMENT_PROCESSOR_TEST; |
| |
| typedef GrGradientEffect INHERITED; |
| }; |
| |
| ///////////////////////////////////////////////////////////////////// |
| |
| GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrLinearGradient); |
| |
| const GrFragmentProcessor* GrLinearGradient::TestCreate(GrProcessorTestData* d) { |
| SkPoint points[] = {{d->fRandom->nextUScalar1(), d->fRandom->nextUScalar1()}, |
| {d->fRandom->nextUScalar1(), d->fRandom->nextUScalar1()}}; |
| |
| SkColor colors[kMaxRandomGradientColors]; |
| SkScalar stopsArray[kMaxRandomGradientColors]; |
| SkScalar* stops = stopsArray; |
| SkShader::TileMode tm; |
| int colorCount = RandomGradientParams(d->fRandom, colors, &stops, &tm); |
| SkAutoTUnref<SkShader> shader(SkGradientShader::CreateLinear(points, |
| colors, stops, colorCount, |
| tm)); |
| const GrFragmentProcessor* fp = shader->asFragmentProcessor(d->fContext, |
| GrTest::TestMatrix(d->fRandom), NULL, kNone_SkFilterQuality); |
| GrAlwaysAssert(fp); |
| return fp; |
| } |
| |
| ///////////////////////////////////////////////////////////////////// |
| |
| void GrGLLinearGradient::emitCode(EmitArgs& args) { |
| const GrLinearGradient& ge = args.fFp.cast<GrLinearGradient>(); |
| this->emitUniforms(args.fBuilder, ge); |
| SkString t = args.fBuilder->getFragmentShaderBuilder()->ensureFSCoords2D(args.fCoords, 0); |
| t.append(".x"); |
| this->emitColor(args.fBuilder, ge, t.c_str(), args.fOutputColor, args.fInputColor, |
| args.fSamplers); |
| } |
| |
| ///////////////////////////////////////////////////////////////////// |
| |
| const GrFragmentProcessor* SkLinearGradient::asFragmentProcessor( |
| GrContext* context, |
| const SkMatrix& viewm, |
| const SkMatrix* localMatrix, |
| SkFilterQuality) const { |
| SkASSERT(context); |
| |
| SkMatrix matrix; |
| if (!this->getLocalMatrix().invert(&matrix)) { |
| return nullptr; |
| } |
| if (localMatrix) { |
| SkMatrix inv; |
| if (!localMatrix->invert(&inv)) { |
| return nullptr; |
| } |
| matrix.postConcat(inv); |
| } |
| matrix.postConcat(fPtsToUnit); |
| |
| SkAutoTUnref<const GrFragmentProcessor> inner( |
| GrLinearGradient::Create(context, *this, matrix, fTileMode)); |
| return GrFragmentProcessor::MulOutputByInputAlpha(inner); |
| } |
| |
| |
| #endif |
| |
| #ifndef SK_IGNORE_TO_STRING |
| void SkLinearGradient::toString(SkString* str) const { |
| str->append("SkLinearGradient ("); |
| |
| str->appendf("start: (%f, %f)", fStart.fX, fStart.fY); |
| str->appendf(" end: (%f, %f) ", fEnd.fX, fEnd.fY); |
| |
| this->INHERITED::toString(str); |
| |
| str->append(")"); |
| } |
| #endif |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| #include "SkNx.h" |
| |
| static const SkLinearGradient::LinearGradientContext::Rec* |
| find_forward(const SkLinearGradient::LinearGradientContext::Rec rec[], float tiledX) { |
| SkASSERT(tiledX >= 0 && tiledX <= 1); |
| |
| SkASSERT(rec[0].fPos >= 0 && rec[0].fPos <= 1); |
| SkASSERT(rec[1].fPos >= 0 && rec[1].fPos <= 1); |
| SkASSERT(rec[0].fPos <= rec[1].fPos); |
| rec += 1; |
| while (rec->fPos < tiledX) { |
| SkASSERT(rec[0].fPos >= 0 && rec[0].fPos <= 1); |
| SkASSERT(rec[1].fPos >= 0 && rec[1].fPos <= 1); |
| SkASSERT(rec[0].fPos <= rec[1].fPos); |
| rec += 1; |
| } |
| return rec - 1; |
| } |
| |
| static const SkLinearGradient::LinearGradientContext::Rec* |
| find_backward(const SkLinearGradient::LinearGradientContext::Rec rec[], float tiledX) { |
| SkASSERT(tiledX >= 0 && tiledX <= 1); |
| |
| SkASSERT(rec[0].fPos >= 0 && rec[0].fPos <= 1); |
| SkASSERT(rec[1].fPos >= 0 && rec[1].fPos <= 1); |
| SkASSERT(rec[0].fPos <= rec[1].fPos); |
| while (tiledX < rec->fPos) { |
| rec -= 1; |
| SkASSERT(rec[0].fPos >= 0 && rec[0].fPos <= 1); |
| SkASSERT(rec[1].fPos >= 0 && rec[1].fPos <= 1); |
| SkASSERT(rec[0].fPos <= rec[1].fPos); |
| } |
| return rec; |
| } |
| |
| template <bool apply_alpha> SkPMColor trunc_from_255(const Sk4f& x) { |
| SkPMColor c; |
| x.toBytes((uint8_t*)&c); |
| if (apply_alpha) { |
| c = SkPreMultiplyARGB(SkGetPackedA32(c), SkGetPackedR32(c), |
| SkGetPackedG32(c), SkGetPackedB32(c)); |
| } |
| return c; |
| } |
| |
| template <bool apply_alpha> void fill(SkPMColor dst[], int count, |
| const Sk4f& c4, const Sk4f& c4other) { |
| sk_memset32_dither(dst, trunc_from_255<apply_alpha>(c4), |
| trunc_from_255<apply_alpha>(c4other), count); |
| } |
| |
| template <bool apply_alpha> void fill(SkPMColor dst[], int count, const Sk4f& c4) { |
| // Assumes that c4 does not need to be dithered. |
| sk_memset32(dst, trunc_from_255<apply_alpha>(c4), count); |
| } |
| |
| /* |
| * TODOs |
| * |
| * - tilemodes |
| * - interp before or after premul |
| * - perspective |
| * - optimizations |
| * - use fixed (32bit or 16bit) instead of floats? |
| */ |
| |
| static Sk4f lerp_color(float fx, const SkLinearGradient::LinearGradientContext::Rec* rec) { |
| const float p0 = rec[0].fPos; |
| const Sk4f c0 = rec[0].fColor; |
| const Sk4f c1 = rec[1].fColor; |
| const Sk4f diffc = c1 - c0; |
| const float scale = rec[1].fPosScale; |
| const float t = (fx - p0) * scale; |
| return c0 + Sk4f(t) * diffc; |
| } |
| |
| template <bool apply_alpha> void ramp(SkPMColor dstC[], int n, const Sk4f& c, const Sk4f& dc, |
| const Sk4f& dither0, const Sk4f& dither1) { |
| Sk4f dc2 = dc + dc; |
| Sk4f dc4 = dc2 + dc2; |
| Sk4f cd0 = c + dither0; |
| Sk4f cd1 = c + dc + dither1; |
| Sk4f cd2 = cd0 + dc2; |
| Sk4f cd3 = cd1 + dc2; |
| while (n >= 4) { |
| *dstC++ = trunc_from_255<apply_alpha>(cd0); |
| *dstC++ = trunc_from_255<apply_alpha>(cd1); |
| *dstC++ = trunc_from_255<apply_alpha>(cd2); |
| *dstC++ = trunc_from_255<apply_alpha>(cd3); |
| cd0 = cd0 + dc4; |
| cd1 = cd1 + dc4; |
| cd2 = cd2 + dc4; |
| cd3 = cd3 + dc4; |
| n -= 4; |
| } |
| if (n & 2) { |
| *dstC++ = trunc_from_255<apply_alpha>(cd0); |
| *dstC++ = trunc_from_255<apply_alpha>(cd1); |
| cd0 = cd0 + dc2; |
| } |
| if (n & 1) { |
| *dstC++ = trunc_from_255<apply_alpha>(cd0); |
| } |
| } |
| |
| template <bool apply_alpha, bool dx_is_pos> |
| void SkLinearGradient::LinearGradientContext::shade4_dx_clamp(SkPMColor dstC[], int count, |
| float fx, float dx, float invDx, |
| const float dither[2]) { |
| Sk4f dither0(dither[0]); |
| Sk4f dither1(dither[1]); |
| const Rec* rec = fRecs.begin(); |
| |
| const Sk4f dx4 = Sk4f(dx); |
| SkDEBUGCODE(SkPMColor* endDstC = dstC + count;) |
| |
| if (dx_is_pos) { |
| if (fx < 0) { |
| int n = SkTMin(SkFloatToIntFloor(-fx * invDx) + 1, count); |
| fill<apply_alpha>(dstC, n, rec[0].fColor); |
| count -= n; |
| dstC += n; |
| fx += n * dx; |
| SkASSERT(0 == count || fx >= 0); |
| if (n & 1) { |
| SkTSwap(dither0, dither1); |
| } |
| } |
| } else { // dx < 0 |
| if (fx > 1) { |
| int n = SkTMin(SkFloatToIntFloor((1 - fx) * invDx) + 1, count); |
| fill<apply_alpha>(dstC, n, rec[fRecs.count() - 1].fColor); |
| count -= n; |
| dstC += n; |
| fx += n * dx; |
| SkASSERT(0 == count || fx <= 1); |
| if (n & 1) { |
| SkTSwap(dither0, dither1); |
| } |
| } |
| } |
| SkASSERT(count >= 0); |
| |
| const Rec* r; |
| if (dx_is_pos) { |
| r = fRecs.begin(); // start at the beginning |
| } else { |
| r = fRecs.begin() + fRecs.count() - 2; // start at the end |
| } |
| |
| while (count > 0) { |
| if (dx_is_pos) { |
| if (fx >= 1) { |
| fill<apply_alpha>(dstC, count, rec[fRecs.count() - 1].fColor); |
| return; |
| } |
| } else { // dx < 0 |
| if (fx <= 0) { |
| fill<apply_alpha>(dstC, count, rec[0].fColor); |
| return; |
| } |
| } |
| |
| if (dx_is_pos) { |
| r = find_forward(r, fx); |
| } else { |
| r = find_backward(r, fx); |
| } |
| SkASSERT(r >= fRecs.begin() && r < fRecs.begin() + fRecs.count() - 1); |
| |
| const float p0 = r[0].fPos; |
| const Sk4f c0 = r[0].fColor; |
| const float p1 = r[1].fPos; |
| const Sk4f diffc = Sk4f(r[1].fColor) - c0; |
| const float scale = r[1].fPosScale; |
| const float t = (fx - p0) * scale; |
| const Sk4f c = c0 + Sk4f(t) * diffc; |
| const Sk4f dc = diffc * dx4 * Sk4f(scale); |
| |
| int n; |
| if (dx_is_pos) { |
| n = SkTMin((int)((p1 - fx) * invDx) + 1, count); |
| } else { |
| n = SkTMin((int)((p0 - fx) * invDx) + 1, count); |
| } |
| |
| fx += n * dx; |
| count -= n; |
| SkASSERT(count >= 0); |
| if (dx_is_pos) { |
| SkASSERT(0 == count || fx >= p1); |
| } else { |
| SkASSERT(0 == count || fx <= p0); |
| } |
| |
| ramp<apply_alpha>(dstC, n, c, dc, dither0, dither1); |
| dstC += n; |
| SkASSERT(dstC <= endDstC); |
| |
| if (n & 1) { |
| SkTSwap(dither0, dither1); |
| } |
| } |
| } |
| |
| void SkLinearGradient::LinearGradientContext::shade4_clamp(int x, int y, SkPMColor dstC[], |
| int count) { |
| SkASSERT(count > 0); |
| SkASSERT(kLinear_MatrixClass == fDstToIndexClass); |
| |
| SkPoint srcPt; |
| fDstToIndexProc(fDstToIndex, x + SK_ScalarHalf, y + SK_ScalarHalf, &srcPt); |
| float fx = srcPt.x(); |
| const float dx = fDstToIndex.getScaleX(); |
| |
| // Default our dither bias values to 1/2, (rounding), which is no dithering |
| float dither0 = 0.5f; |
| float dither1 = 0.5f; |
| if (fDither) { |
| const float ditherCell[] = { |
| 1/8.0f, 5/8.0f, |
| 7/8.0f, 3/8.0f, |
| }; |
| const int rowIndex = (y & 1) << 1; |
| dither0 = ditherCell[rowIndex]; |
| dither1 = ditherCell[rowIndex + 1]; |
| if (x & 1) { |
| SkTSwap(dither0, dither1); |
| } |
| } |
| const float dither[2] = { dither0, dither1 }; |
| const float invDx = 1 / dx; |
| |
| if (!SkScalarIsFinite(invDx)) { // dx is effectively zero, gradient is vertical |
| Sk4f c = lerp_color(fx, find_forward(fRecs.begin(), SkTPin(fx, 0.0f, 1.0f))); |
| if (fApplyAlphaAfterInterp) { |
| fill<true>(dstC, count, c + dither0, c + dither1); |
| } else { |
| fill<false>(dstC, count, c + dither0, c + dither1); |
| } |
| return; |
| } |
| |
| if (dx > 0) { |
| if (fApplyAlphaAfterInterp) { |
| this->shade4_dx_clamp<true, true>(dstC, count, fx, dx, invDx, dither); |
| } else { |
| this->shade4_dx_clamp<false, true>(dstC, count, fx, dx, invDx, dither); |
| } |
| } else { |
| if (fApplyAlphaAfterInterp) { |
| this->shade4_dx_clamp<true, false>(dstC, count, fx, dx, invDx, dither); |
| } else { |
| this->shade4_dx_clamp<false, false>(dstC, count, fx, dx, invDx, dither); |
| } |
| } |
| } |
| |
