1234567891011121314151617181920212223242526272829 |
- // Copyright 2019 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"
- // HASH=092739b4cd5d732a27c07ced8ef45f01
- REG_FIDDLE(Bitmap_extractAlpha_2, 256, 160, false, 0) {
- void draw(SkCanvas* canvas) {
- auto radiusToSigma = [](SkScalar radius) -> SkScalar {
- static const SkScalar kBLUR_SIGMA_SCALE = 0.57735f;
- return radius > 0 ? kBLUR_SIGMA_SCALE * radius + 0.5f : 0.0f;
- };
- SkBitmap alpha, bitmap;
- bitmap.allocN32Pixels(100, 100);
- SkCanvas offscreen(bitmap);
- offscreen.clear(0);
- SkPaint paint;
- paint.setAntiAlias(true);
- paint.setColor(SK_ColorBLUE);
- paint.setStyle(SkPaint::kStroke_Style);
- paint.setStrokeWidth(20);
- offscreen.drawCircle(50, 50, 39, paint);
- offscreen.flush();
- paint.setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, radiusToSigma(25)));
- SkIPoint offset;
- bitmap.extractAlpha(&alpha, &paint, &offset);
- paint.setColor(SK_ColorRED);
- canvas->drawBitmap(bitmap, 0, -offset.fY, &paint);
- canvas->drawBitmap(alpha, 100 + offset.fX, 0, &paint);
- }
- } // END FIDDLE
|