| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "gm/gm.h" |
| #include "include/core/SkCanvas.h" |
| #include "include/core/SkColor.h" |
| #include "include/core/SkFont.h" |
| #include "include/core/SkFontTypes.h" |
| #include "include/core/SkImage.h" |
| #include "include/core/SkImageFilter.h" |
| #include "include/core/SkPaint.h" |
| #include "include/core/SkPoint.h" |
| #include "include/core/SkRect.h" |
| #include "include/core/SkRefCnt.h" |
| #include "include/core/SkScalar.h" |
| #include "include/core/SkShader.h" |
| #include "include/core/SkSize.h" |
| #include "include/core/SkString.h" |
| #include "include/core/SkSurface.h" |
| #include "include/core/SkTileMode.h" |
| #include "include/core/SkTypeface.h" |
| #include "include/core/SkTypes.h" |
| #include "include/effects/SkGradientShader.h" |
| #include "include/effects/SkImageFilters.h" |
| #include "tools/ToolUtils.h" |
| |
| #include <utility> |
| |
| static sk_sp<SkImage> make_src(int w, int h) { |
| sk_sp<SkSurface> surface(SkSurfaces::Raster(SkImageInfo::MakeN32Premul(w, h))); |
| SkCanvas* canvas = surface->getCanvas(); |
| |
| SkPaint paint; |
| SkPoint pts[] = { {0, 0}, {SkIntToScalar(w), SkIntToScalar(h)} }; |
| SkColor colors[] = { |
| SK_ColorTRANSPARENT, SK_ColorGREEN, SK_ColorCYAN, |
| SK_ColorRED, SK_ColorMAGENTA, SK_ColorWHITE, |
| }; |
| paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, std::size(colors), |
| SkTileMode::kClamp)); |
| canvas->drawPaint(paint); |
| return surface->makeImageSnapshot(); |
| } |
| |
| static sk_sp<SkImage> make_dst(int w, int h) { |
| sk_sp<SkSurface> surface(SkSurfaces::Raster(SkImageInfo::MakeN32Premul(w, h))); |
| SkCanvas* canvas = surface->getCanvas(); |
| |
| SkPaint paint; |
| SkPoint pts[] = { {0, SkIntToScalar(h)}, {SkIntToScalar(w), 0} }; |
| SkColor colors[] = { |
| SK_ColorBLUE, SK_ColorYELLOW, SK_ColorBLACK, SK_ColorGREEN, |
| SK_ColorGRAY, |
| }; |
| paint.setShader(SkGradientShader::MakeLinear(pts, colors, nullptr, std::size(colors), |
| SkTileMode::kClamp)); |
| canvas->drawPaint(paint); |
| return surface->makeImageSnapshot(); |
| } |
| |
| static void show_k_text(SkCanvas* canvas, SkScalar x, SkScalar y, const SkScalar k[]) { |
| SkFont font(ToolUtils::create_portable_typeface(), 24); |
| font.setEdging(SkFont::Edging::kAntiAlias); |
| SkPaint paint; |
| paint.setAntiAlias(true); |
| for (int i = 0; i < 4; ++i) { |
| SkString str; |
| str.appendScalar(k[i]); |
| SkScalar width = font.measureText(str.c_str(), str.size(), SkTextEncoding::kUTF8); |
| canvas->drawString(str, x, y + font.getSize(), font, paint); |
| x += width + SkIntToScalar(10); |
| } |
| } |
| |
| class ArithmodeGM : public skiagm::GM { |
| SkString onShortName() override { return SkString("arithmode"); } |
| |
| SkISize onISize() override { return {640, 572}; } |
| |
| void onDraw(SkCanvas* canvas) override { |
| constexpr int WW = 100, |
| HH = 32; |
| |
| sk_sp<SkImage> src = make_src(WW, HH); |
| sk_sp<SkImage> dst = make_dst(WW, HH); |
| sk_sp<SkImageFilter> srcFilter = SkImageFilters::Image(src); |
| sk_sp<SkImageFilter> dstFilter = SkImageFilters::Image(dst); |
| |
| constexpr SkScalar one = SK_Scalar1; |
| constexpr SkScalar K[] = { |
| 0, 0, 0, 0, |
| 0, 0, 0, one, |
| 0, one, 0, 0, |
| 0, 0, one, 0, |
| 0, one, one, 0, |
| 0, one, -one, 0, |
| 0, one/2, one/2, 0, |
| 0, one/2, one/2, one/4, |
| 0, one/2, one/2, -one/4, |
| one/4, one/2, one/2, 0, |
| -one/4, one/2, one/2, 0, |
| }; |
| |
| const SkScalar* k = K; |
| const SkScalar* stop = k + std::size(K); |
| // Many of the Arithmetic filters have a 4th coefficient that's not zero, which means they |
| // affect transparent black. 'rect' is used as a crop filter to make sure they don't |
| // overwrite each other. |
| const SkRect rect = SkRect::MakeWH(WW, HH); |
| SkScalar gap = SkIntToScalar(WW + 20); |
| while (k < stop) { |
| { |
| SkAutoCanvasRestore acr(canvas, true); |
| canvas->drawImage(src, 0, 0); |
| canvas->translate(gap, 0); |
| canvas->drawImage(dst, 0, 0); |
| canvas->translate(gap, 0); |
| SkPaint paint; |
| paint.setImageFilter(SkImageFilters::Arithmetic(k[0], k[1], k[2], k[3], true, |
| dstFilter, srcFilter, rect)); |
| canvas->saveLayer(nullptr, &paint); |
| canvas->restore(); |
| |
| canvas->translate(gap, 0); |
| show_k_text(canvas, 0, 0, k); |
| } |
| |
| k += 4; |
| canvas->translate(0, HH + 12); |
| } |
| |
| // Draw two special cases to test enforcePMColor. In these cases, we |
| // draw the dst bitmap twice, the first time it is halved and inverted, |
| // leading to invalid premultiplied colors. If we enforcePMColor, these |
| // invalid values should be clamped, and will not contribute to the |
| // second draw. |
| for (int i = 0; i < 2; i++) { |
| const bool enforcePMColor = (i == 0); |
| |
| { |
| SkAutoCanvasRestore acr(canvas, true); |
| canvas->translate(gap, 0); |
| canvas->drawImage(dst, 0, 0); |
| canvas->translate(gap, 0); |
| |
| sk_sp<SkImageFilter> bg = |
| SkImageFilters::Arithmetic(0, 0, -one / 2, 1, enforcePMColor, dstFilter, |
| nullptr, nullptr); |
| SkPaint p; |
| p.setImageFilter(SkImageFilters::Arithmetic(0, one / 2, -one, 1, true, |
| std::move(bg), dstFilter, rect)); |
| canvas->saveLayer(nullptr, &p); |
| canvas->restore(); |
| canvas->translate(gap, 0); |
| |
| // Label |
| SkFont font(ToolUtils::create_portable_typeface(), 24); |
| SkString str(enforcePMColor ? "enforcePM" : "no enforcePM"); |
| canvas->drawString(str, 0, font.getSize(), font, SkPaint()); |
| } |
| canvas->translate(0, HH + 12); |
| } |
| } |
| |
| private: |
| using INHERITED = GM; |
| }; |
| DEF_GM( return new ArithmodeGM; ) |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #include "include/effects/SkBlenders.h" |
| |
| class ArithmodeBlenderGM : public skiagm::GM { |
| float fK1, fK2, fK3, fK4; |
| sk_sp<SkImage> fSrc, fDst, fChecker; |
| sk_sp<SkShader> fSrcShader, fDstShader; |
| sk_sp<SkRuntimeEffect> fRuntimeEffect; |
| |
| SkString onShortName() override { return SkString("arithmode_blender"); } |
| |
| static constexpr int W = 200; |
| static constexpr int H = 200; |
| |
| SkISize onISize() override { return {(W + 30) * 2, (H + 30) * 4}; } |
| |
| void onOnceBeforeDraw() override { |
| // Prepare a runtime effect for this blend. |
| static constexpr char kShader[] = R"( |
| uniform shader srcImage; |
| uniform shader dstImage; |
| uniform blender arithBlend; |
| half4 main(float2 xy) { |
| return arithBlend.eval(srcImage.eval(xy), dstImage.eval(xy)); |
| } |
| )"; |
| auto [effect, error] = SkRuntimeEffect::MakeForShader(SkString(kShader)); |
| SkASSERT(effect); |
| fRuntimeEffect = effect; |
| |
| // Start with interesting K-values, in case we're drawn without calling onAnimate(). |
| fK1 = -0.25f; |
| fK2 = 0.25f; |
| fK3 = 0.25f; |
| fK4 = 0; |
| |
| fSrc = make_src(W, H); |
| fDst = make_dst(W, H); |
| fSrcShader = fSrc->makeShader(SkTileMode::kClamp, SkTileMode::kClamp, SkSamplingOptions()); |
| fDstShader = fDst->makeShader(SkTileMode::kClamp, SkTileMode::kClamp, SkSamplingOptions()); |
| |
| fChecker = ToolUtils::create_checkerboard_image(W, H, 0xFFBBBBBB, 0xFFEEEEEE, 8); |
| } |
| |
| bool onAnimate(double nanos) override { |
| double theta = nanos * 1e-6 * 0.001; |
| fK1 = sin(theta + 0) * 0.25; |
| fK2 = cos(theta + 1) * 0.25; |
| fK3 = sin(theta + 2) * 0.25; |
| fK4 = 0.5; |
| return true; |
| } |
| |
| void onDraw(SkCanvas* canvas) override { |
| const SkRect rect = SkRect::MakeWH(W, H); |
| |
| canvas->drawImage(fSrc, 10, 10); |
| canvas->drawImage(fDst, 10, 10 + H + 10); |
| |
| SkSamplingOptions sampling; |
| sk_sp<SkBlender> blender = SkBlenders::Arithmetic(fK1, fK2, fK3, fK4, |
| /*enforcePremul=*/true); |
| canvas->translate(10 + W + 10, 10); |
| |
| // All three images drawn below should appear identical. |
| // Draw via blend step |
| SkPaint blenderPaint; |
| canvas->drawImage(fChecker, 0, 0); |
| canvas->saveLayer(&rect, nullptr); |
| canvas->drawImage(fDst, 0, 0); |
| blenderPaint.setBlender(blender); |
| canvas->drawImage(fSrc, 0, 0, sampling, &blenderPaint); |
| canvas->restore(); |
| |
| canvas->translate(0, 10 + H); |
| |
| // Draw via SkImageFilters::Blend (should appear the same as above) |
| SkPaint imageFilterPaint; |
| canvas->drawImage(fChecker, 0, 0); |
| imageFilterPaint.setImageFilter( |
| SkImageFilters::Blend(blender, |
| /*background=*/nullptr, |
| /*foreground=*/SkImageFilters::Image(fSrc, sampling))); |
| canvas->drawImage(fDst, 0, 0, sampling, &imageFilterPaint); |
| |
| canvas->translate(0, 10 + H); |
| |
| // Draw via SkShaders::Blend (should still appear the same as above) |
| SkPaint shaderBlendPaint; |
| canvas->drawImage(fChecker, 0, 0); |
| shaderBlendPaint.setShader(SkShaders::Blend(blender, fDstShader, fSrcShader)); |
| canvas->drawRect(rect, shaderBlendPaint); |
| |
| canvas->translate(0, 10 + H); |
| |
| // Draw via runtime effect (should still appear the same as above) |
| SkPaint runtimePaint; |
| canvas->drawImage(fChecker, 0, 0); |
| SkRuntimeEffect::ChildPtr children[] = {fSrcShader, fDstShader, blender}; |
| runtimePaint.setShader(fRuntimeEffect->makeShader(/*uniforms=*/{}, children)); |
| canvas->drawRect(rect, runtimePaint); |
| } |
| |
| private: |
| using INHERITED = GM; |
| }; |
| DEF_GM( return new ArithmodeBlenderGM; ) |