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/*
* 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 "include/core/SkCanvas.h"
#include "include/core/SkShader.h"
#include "include/effects/SkGradientShader.h"
#include "samplecode/DecodeFile.h"
#include "samplecode/Sample.h"
#include "tools/Resources.h"
namespace {
static sk_sp<SkShader> make_bitmapfade(const SkBitmap& bm) {
SkPoint pts[2] = {
{0, 0},
{0, (float)bm.height()},
};
SkColor colors[2] = {
SkColorSetARGB(255, 0, 0, 0),
SkColorSetARGB(0, 0, 0, 0),
};
return SkShaders::Blend(SkBlendMode::kDstIn,
bm.makeShader(),
SkGradientShader::MakeLinear(pts, colors, nullptr, 2,
SkTileMode::kClamp));
}
static sk_sp<SkShader> make_blend_shader() {
SkPoint pts[2];
SkColor colors[2];
pts[0].set(0, 0);
pts[1].set(SkIntToScalar(100), 0);
colors[0] = SK_ColorRED;
colors[1] = SK_ColorBLUE;
auto shaderA = SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkTileMode::kClamp);
pts[0].set(0, 0);
pts[1].set(0, SkIntToScalar(100));
colors[0] = SK_ColorBLACK;
colors[1] = SkColorSetARGB(0x80, 0, 0, 0);
auto shaderB = SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkTileMode::kClamp);
return SkShaders::Blend(SkBlendMode::kDstIn, std::move(shaderA), std::move(shaderB));
}
struct ShaderView : public Sample {
sk_sp<SkShader> fShader;
sk_sp<SkShader> fShaderFade;
SkBitmap fBitmap;
void onOnceBeforeDraw() override {
decode_file(GetResourceAsData("images/dog.jpg"), &fBitmap);
fShader = make_blend_shader();
fShaderFade = make_bitmapfade(fBitmap);
}
SkString name() override { return SkString("Shaders"); }
void onDrawContent(SkCanvas* canvas) override {
canvas->drawBitmap(fBitmap, 0, 0);
canvas->translate(20, 120);
SkPaint paint;
paint.setColor(SK_ColorGREEN);
canvas->drawRect(SkRect{0, 0, 100, 100}, paint);
paint.setShader(fShader);
canvas->drawRect(SkRect{0, 0, 100, 100}, paint);
canvas->translate(SkIntToScalar(110), 0);
paint.setShader(nullptr);
canvas->drawRect(SkRect{0, 0, 120, 80}, paint);
paint.setShader(fShaderFade);
canvas->drawRect(SkRect{0, 0, 120, 80}, paint);
}
};
} // namespace
DEF_SAMPLE( return new ShaderView(); )
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