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Named Fiddles
Skia Fiddle
Skia Version:
bd99c0
static SkBitmap make_alpha_image(int w, int h) { SkBitmap bm; bm.allocPixels(SkImageInfo::MakeA8(w, h)); bm.eraseARGB(10, 0, 0 , 0); for (int y = 0; y < bm.height(); ++y) { for (int x = y; x < bm.width(); ++x) { *bm.getAddr8(x, y) = 0xFF; } } bm.setImmutable(); return bm; } static sk_sp<SkColorFilter> make_color_filter() { SkScalar colorMatrix[20] = { 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0.5, 0.5, 0, 0, 0, 0.5, 0.5, 0}; // mix G and A. return SkColorFilters::Matrix(colorMatrix); } void draw(SkCanvas* canvas) { auto image = SkImage::MakeFromBitmap(make_alpha_image(96, 96)); SkPaint paint; paint.setColorFilter(make_color_filter()); paint.setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, 10.0f, false)); canvas->drawImage(image.get(), 16, 16, &paint); paint.setColorFilter(nullptr); paint.setShader(SkShaders::Color(SK_ColorCYAN)); canvas->drawImage(image.get(), 144, 16, &paint); paint.setColorFilter(make_color_filter()); canvas->drawImage(image.get(), 16, 144, &paint); paint.setMaskFilter(nullptr); canvas->drawImage(image.get(), 144, 144, &paint); }
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