aosp12/external/skia/docs/examples/blur_alpha_img.cpp

37 lines
1.3 KiB
C++

// Copyright 2020 Google LLC.
// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
#include "tools/fiddle/examples.h"
REG_FIDDLE(blur_alpha_img, 256, 256, false, 0) {
sk_sp<SkImage> foo() {
int w = 240, h = 240;
SkScalar scale = 10.0f;
SkPath path;
static const int8_t pts[] = {2, 2, 1, 3, 0, 3, 2, 1, 3, 1, 4, 0, 4, 1,
5, 1, 4, 2, 4, 3, 2, 5, 2, 4, 3, 3, 2, 3};
path.moveTo(2 * scale, 3 * scale);
for (size_t i = 0; i < sizeof(pts) / sizeof(pts[0]); i += 2) {
path.lineTo(pts[i] * scale, pts[i + 1] * scale);
}
path.close();
SkMatrix matrix = SkMatrix::Scale(4 * scale, 4 * scale);
SkPaint paint;
paint.setPathEffect(SkPath2DPathEffect::Make(matrix, path));
paint.setAntiAlias(true);
SkRect bounds{-4 * scale, -4 * scale, (float)w, (float)h};
SkBitmap bm;
bm.allocPixels(SkImageInfo::MakeA8(w, h));
SkCanvas c(bm);
c.clear(0);
c.drawRect(bounds, paint);
return bm.asImage();
}
void draw(SkCanvas* canvas) {
auto a8img = foo();
SkPaint paint;
paint.setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, 2.0f, 0));
paint.setColor(0xFF008000);
canvas->drawImage(a8img, 8, 8, SkSamplingOptions(), &paint);
}
} // END FIDDLE