blob: 7fd0dad1b28454d44028db5dfc4ce5cb60d63fd9 [file] [log] [blame]
/*
* Copyright 2015 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/SkBitmap.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkImage.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPath.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/SkTypes.h"
#include "include/effects/SkGradientShader.h"
#include "tools/ToolUtils.h"
static sk_sp<SkImage> make_image(SkCanvas* origCanvas, int w, int h) {
SkImageInfo info = SkImageInfo::MakeN32Premul(w, h);
auto surface(ToolUtils::makeSurface(origCanvas, info));
SkCanvas* canvas = surface->getCanvas();
ToolUtils::draw_checkerboard(canvas, SK_ColorRED, SK_ColorGREEN, w / 10);
return surface->makeImageSnapshot();
}
namespace skiagm {
class PerspShadersGM : public GM {
public:
PerspShadersGM(bool doAA) : fDoAA(doAA) { }
protected:
SkString onShortName() override {
SkString name;
name.printf("persp_shaders_%s",
fDoAA ? "aa" : "bw");
return name;
}
SkISize onISize() override {
return SkISize::Make(kCellSize*kNumCols, kCellSize*kNumRows);
}
void onOnceBeforeDraw() override {
fBitmapImage = ToolUtils::create_checkerboard_image(
kCellSize, kCellSize, SK_ColorBLUE, SK_ColorYELLOW, kCellSize / 10);
SkPoint pts1[] = {
{ 0, 0 },
{ SkIntToScalar(kCellSize), SkIntToScalar(kCellSize) }
};
SkPoint pts2[] = {
{ 0, 0 },
{ 0, SkIntToScalar(kCellSize) }
};
constexpr SkColor colors[] = {
SK_ColorRED, SK_ColorGREEN, SK_ColorRED, SK_ColorGREEN, SK_ColorRED
};
constexpr SkScalar pos[] = { 0, 0.25f, 0.5f, 0.75f, SK_Scalar1 };
fLinearGrad1 = SkGradientShader::MakeLinear(pts1, colors, pos, std::size(colors),
SkTileMode::kClamp);
fLinearGrad2 = SkGradientShader::MakeLinear(pts2, colors, pos, std::size(colors),
SkTileMode::kClamp);
fPerspMatrix.reset();
fPerspMatrix.setPerspY(SK_Scalar1 / 50);
fPath.moveTo(0, 0);
fPath.lineTo(0, SkIntToScalar(kCellSize));
fPath.lineTo(kCellSize/2.0f, kCellSize/2.0f);
fPath.lineTo(SkIntToScalar(kCellSize), SkIntToScalar(kCellSize));
fPath.lineTo(SkIntToScalar(kCellSize), 0);
fPath.close();
}
void drawRow(SkCanvas* canvas, const SkSamplingOptions& sampling) {
SkPaint filterPaint;
filterPaint.setAntiAlias(fDoAA);
SkPaint pathPaint;
pathPaint.setShader(fBitmapImage->makeShader(sampling));
pathPaint.setAntiAlias(fDoAA);
SkPaint gradPaint1;
gradPaint1.setShader(fLinearGrad1);
gradPaint1.setAntiAlias(fDoAA);
SkPaint gradPaint2;
gradPaint2.setShader(fLinearGrad2);
gradPaint2.setAntiAlias(fDoAA);
SkRect r = SkRect::MakeWH(SkIntToScalar(kCellSize), SkIntToScalar(kCellSize));
canvas->save();
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawImageRect(fBitmapImage, r, sampling, &filterPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawImage(fImage.get(), 0, 0, sampling, &filterPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawRect(r, pathPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawPath(fPath, pathPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawRect(r, gradPaint1);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawPath(fPath, gradPaint2);
canvas->restore();
canvas->restore();
}
void onDraw(SkCanvas* canvas) override {
if (!fImage || !fImage->isValid(canvas->recordingContext())) {
fImage = make_image(canvas, kCellSize, kCellSize);
}
this->drawRow(canvas, SkSamplingOptions(SkFilterMode::kNearest));
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, SkSamplingOptions(SkFilterMode::kLinear));
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, SkSamplingOptions(SkFilterMode::kLinear,
SkMipmapMode::kNearest));
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, SkSamplingOptions(SkCubicResampler::Mitchell()));
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, SkSamplingOptions::Aniso(16));
canvas->translate(0, SkIntToScalar(kCellSize));
}
private:
inline static constexpr int kCellSize = 50;
inline static constexpr int kNumRows = 5;
inline static constexpr int kNumCols = 6;
bool fDoAA;
SkPath fPath;
sk_sp<SkShader> fLinearGrad1;
sk_sp<SkShader> fLinearGrad2;
SkMatrix fPerspMatrix;
sk_sp<SkImage> fImage;
sk_sp<SkImage> fBitmapImage;
using INHERITED = GM;
};
DEF_GM(return new PerspShadersGM(true);)
DEF_GM(return new PerspShadersGM(false);)
} // namespace skiagm
//////////////////////////////////////////////////////////////////////////////
#include "tools/Resources.h"
static SkPath make_path() {
SkRandom rand;
auto rand_pt = [&rand]() {
auto x = rand.nextF();
auto y = rand.nextF();
return SkPoint{x * 400, y * 400};
};
SkPath path;
for (int i = 0; i < 4; ++i) {
SkPoint pts[6];
for (auto& p : pts) {
p = rand_pt();
}
path.moveTo(pts[0]).quadTo(pts[1], pts[2]).quadTo(pts[3], pts[4]).lineTo(pts[5]);
}
return path;
}
DEF_SIMPLE_GM(perspective_clip, canvas, 800, 800) {
SkPath path = make_path();
auto shader = GetResourceAsImage("images/mandrill_128.png")
->makeShader(SkSamplingOptions(), SkMatrix::Scale(3, 3));
SkPaint paint;
paint.setColor({0.75, 0.75, 0.75, 1});
canvas->drawPath(path, paint);
// This is a crazy perspective matrix, derived from halfplanes3, to draw a shape where
// part of it is "behind" the viewer, hence showing the need for "half-plane" clipping
// when in perspective.
SkMatrix mx;
const SkScalar array[] = {
-1.7866f, 1.3357f, 273.0295f,
-1.0820f, 1.3186f, 135.5196f,
-0.0047f, -0.0015f, 2.1485f,
};
mx.set9(array);
paint.setShader(shader);
canvas->concat(mx);
canvas->drawPath(path, paint);
}