Flutter Engine
The Flutter Engine
Bitmap_extractAlpha.cpp
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1// Copyright 2019 Google LLC.
2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
4REG_FIDDLE(Bitmap_extractAlpha, 256, 100, false, 0) {
5void draw(SkCanvas* canvas) {
6 SkBitmap alpha, bitmap;
7 bitmap.allocN32Pixels(100, 100);
8 SkCanvas offscreen(bitmap);
9 offscreen.clear(0);
11 paint.setAntiAlias(true);
12 paint.setColor(SK_ColorBLUE);
14 paint.setStrokeWidth(20);
15 offscreen.drawCircle(50, 50, 39, paint);
16 bitmap.extractAlpha(&alpha);
17 paint.setColor(SK_ColorRED);
18 canvas->drawImage(bitmap.asImage(), 0, 0, SkSamplingOptions(), &paint);
19 canvas->drawImage(alpha.asImage(), 100, 0, SkSamplingOptions(), &paint);
20}
21} // END FIDDLE
REG_FIDDLE(Bitmap_extractAlpha, 256, 100, false, 0)
constexpr SkColor SK_ColorBLUE
Definition: SkColor.h:135
constexpr SkColor SK_ColorRED
Definition: SkColor.h:126
static void draw(SkCanvas *canvas, SkRect &target, int x, int y)
Definition: aaclip.cpp:27
sk_sp< SkImage > asImage() const
Definition: SkBitmap.cpp:645
void clear(SkColor color)
Definition: SkCanvas.h:1199
void drawImage(const SkImage *image, SkScalar left, SkScalar top)
Definition: SkCanvas.h:1528
void drawCircle(SkScalar cx, SkScalar cy, SkScalar radius, const SkPaint &paint)
Definition: SkCanvas.cpp:2707
@ kStroke_Style
set to stroke geometry
Definition: SkPaint.h:194
const Paint & paint
Definition: color_source.cc:38
Definition: bitmap.py:1