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/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm.h"
#include "SkCanvas.h"
#include "SkGradientShader.h"
#include "SkRandom.h"
static SkShader* make_shader(SkScalar w, SkScalar h) {
const SkColor colors[] = {
SK_ColorRED, SK_ColorCYAN, SK_ColorGREEN, SK_ColorWHITE,
SK_ColorMAGENTA, SK_ColorBLUE, SK_ColorYELLOW,
};
const SkPoint pts[] = { { w/4, 0 }, { 3*w/4, h } };
return SkGradientShader::CreateLinear(pts, colors, nullptr,
SK_ARRAY_COUNT(colors),
SkShader::kMirror_TileMode);
}
class VerticesGM : public skiagm::GM {
SkPoint fPts[9];
SkPoint fTexs[9];
SkColor fColors[9];
SkShader* fShader;
unsigned fAlpha;
public:
VerticesGM(unsigned alpha) : fShader(nullptr), fAlpha(alpha) {
}
virtual ~VerticesGM() {
SkSafeUnref(fShader);
}
protected:
void onOnceBeforeDraw() override {
const SkScalar X = 150;
const SkScalar Y = 150;
fPts[0].set(0, 0); fPts[1].set(X/2, 10); fPts[2].set(X, 0);
fPts[3].set(10, Y/2); fPts[4].set(X/2, Y/2); fPts[5].set(X-10, Y/2);
fPts[6].set(0, Y); fPts[7].set(X/2, Y-10); fPts[8].set(X, Y);
const SkScalar w = 200;
const SkScalar h = 200;
fTexs[0].set(0, 0); fTexs[1].set(w/2, 0); fTexs[2].set(w, 0);
fTexs[3].set(0, h/2); fTexs[4].set(w/2, h/2); fTexs[5].set(w, h/2);
fTexs[6].set(0, h); fTexs[7].set(w/2, h); fTexs[8].set(w, h);
fShader = make_shader(w, h);
SkRandom rand;
for (size_t i = 0; i < SK_ARRAY_COUNT(fColors); ++i) {
fColors[i] = rand.nextU() | 0xFF000000;
}
}
SkString onShortName() override {
SkString name("vertices");
if (0xFF != fAlpha) {
name.appendf("_%02X", fAlpha);
}
return name;
}
SkISize onISize() override {
return SkISize::Make(600, 600);
}
void onDraw(SkCanvas* canvas) override {
// start with the center of a 3x3 grid
static const uint16_t fan[] = {
4,
0, 1, 2, 5, 8, 7, 6, 3, 0
};
const struct {
const SkColor* fColors;
const SkPoint* fTexs;
} rec[] = {
{ fColors, nullptr },
{ nullptr, fTexs },
{ fColors, fTexs },
};
const SkXfermode::Mode modes[] = {
SkXfermode::kSrc_Mode,
SkXfermode::kDst_Mode,
SkXfermode::kModulate_Mode,
};
SkPaint paint;
paint.setShader(fShader);
paint.setAlpha(fAlpha);
canvas->translate(20, 20);
for (size_t j = 0; j < SK_ARRAY_COUNT(modes); ++j) {
SkXfermode* xfer = SkXfermode::Create(modes[j]);
canvas->save();
for (size_t i = 0; i < SK_ARRAY_COUNT(rec); ++i) {
canvas->drawVertices(SkCanvas::kTriangleFan_VertexMode,
SK_ARRAY_COUNT(fPts), fPts,
rec[i].fTexs, rec[i].fColors,
xfer, fan, SK_ARRAY_COUNT(fan), paint);
canvas->translate(200, 0);
}
canvas->restore();
canvas->translate(0, 200);
xfer->unref();
}
}
private:
typedef skiagm::GM INHERITED;
};
/////////////////////////////////////////////////////////////////////////////////////
DEF_GM(return new VerticesGM(0xFF);)
DEF_GM(return new VerticesGM(0x80);)
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