Canvas_MakeRasterDirect.cpp 1.5 KB

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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.
  3. #include "tools/fiddle/examples.h"
  4. // HASH=525285073aae7e53eb8f454a398f880c
  5. REG_FIDDLE(Canvas_MakeRasterDirect, 256, 256, true, 0) {
  6. void draw(SkCanvas* ) {
  7. SkImageInfo info = SkImageInfo::MakeN32Premul(3, 3); // device aligned, 32 bpp, Premultiplied
  8. const size_t minRowBytes = info.minRowBytes(); // bytes used by one bitmap row
  9. const size_t size = info.computeMinByteSize(); // bytes used by all rows
  10. SkAutoTMalloc<SkPMColor> storage(size); // allocate storage for pixels
  11. SkPMColor* pixels = storage.get(); // get pointer to allocated storage
  12. // create a SkCanvas backed by a raster device, and delete it when the
  13. // function goes out of scope.
  14. std::unique_ptr<SkCanvas> canvas = SkCanvas::MakeRasterDirect(info, pixels, minRowBytes);
  15. canvas->clear(SK_ColorWHITE); // white is Unpremultiplied, in ARGB order
  16. canvas->flush(); // ensure that pixels are cleared
  17. SkPMColor pmWhite = pixels[0]; // the Premultiplied format may vary
  18. SkPaint paint; // by default, draws black
  19. canvas->drawPoint(1, 1, paint); // draw in the center
  20. canvas->flush(); // ensure that point was drawn
  21. for (int y = 0; y < info.height(); ++y) {
  22. for (int x = 0; x < info.width(); ++x) {
  23. SkDebugf("%c", *pixels++ == pmWhite ? '-' : 'x');
  24. }
  25. SkDebugf("\n");
  26. }
  27. }
  28. } // END FIDDLE