submodule/skia/docs/examples/ImageInfo_makeColorSpace.cpp

   1 #if 0  // Disabled until updated to use current API.
   2 // Copyright 2019 Google LLC.
   3 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
   4 #include "tools/fiddle/examples.h"
   5 // HASH=fe3c5a755d3dde29bba058a583f18901
   6 REG_FIDDLE(ImageInfo_makeColorSpace, 256, 224, false, 0) {
   7 void draw(SkCanvas* canvas) {
   8     const int width = 256;
   9     const int height = 64;
  10     auto drawLabel = [=](const char* what, bool closeToSRGB) -> void {
  11         SkString string;
  12         string.printf("%s gamma is %s" "close to sRGB", what, closeToSRGB ? "" : "not ");
  13         SkPaint paint;
  14         paint.setAntiAlias(true);
  15         canvas->drawString(string, 20, 56, paint);
  16     };
  17     SkColor  gradColors[] = { 0xFFFF7F00, 0xFF00FF7F,  0xFF0000FF, 0xFF7F7FFF };
  18     SkPoint  gradPoints[] = { { 0, 0 }, { width, 0 }, { width * 2, 0 }, { width * 3, 0 } };
  19     SkPaint gradPaint;
  20     gradPaint.setShader(SkGradientShader::MakeLinear(gradPoints, gradColors, nullptr,
  21             SK_ARRAY_COUNT(gradColors), SkShader::kClamp_TileMode));
  22     canvas->drawRect(SkRect::MakeWH(width, height), gradPaint);
  23     drawLabel("canvas", canvas->imageInfo().gammaCloseToSRGB());
  24     SkBitmap bitmap;
  25     SkImageInfo offscreenInfo = SkImageInfo::MakeS32(width, height, kPremul_SkAlphaType);
  26     bitmap.allocPixels(offscreenInfo);
  27     SkCanvas sRGBOffscreen(bitmap);
  28     sRGBOffscreen.drawRect(SkRect::MakeWH(width, height), gradPaint);
  29     canvas->translate(0, 80);
  30     canvas->drawBitmap(bitmap, 0, 0);
  31     drawLabel("offscreen", offscreenInfo.gammaCloseToSRGB());
  32     SkImageInfo linearGamma =
  33             offscreenInfo.makeColorSpace(offscreenInfo.colorSpace()->makeLinearGamma());
  34     bitmap.allocPixels(linearGamma);
  35     SkCanvas lgOffscreen(bitmap);
  36     lgOffscreen.drawRect(SkRect::MakeWH(width, height), gradPaint);
  37     canvas->translate(0, 80);
  38     canvas->drawBitmap(bitmap, 0, 0);
  39     drawLabel("linear", linearGamma.gammaCloseToSRGB());
  40 }
  41 }  // END FIDDLE
  42 #endif  // Disabled until updated to use current API.