blob: b76c9c05248f42c1bd99c486a76ebb00f6c3351c [file] [log] [blame]
/*
* 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(SkSurface::MakeRasterN32Premul(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(SkSurface::MakeRasterN32Premul(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);
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, nullptr));
canvas->saveLayer(&rect, &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, nullptr));
canvas->saveLayer(&rect, &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; )