skia2/docs/examples/Paint_117.cpp
Hal Canary 83c2f70b51 Compile all fiddle examples locally
Motivation: it would be a good idea if the API documentation examples
were checked into the skia repository, so we could make sure they
compile as part of the commit queue.

Fiddle would make/update a named fiddle each time it gets a new
commit of Skia, extracted from the code in the examples/ directory.
The docs would point at those named fiddles.  Named fiddles have urls
in the form:

    https://fiddle.skia.org/c/@Bitmap_000

Then we would stick a link to the example into the header documentation
like this:

    /** Allocates the pixel memory for the bitmap, given its dimensions
        and SkColorType. Returns true on success, where success means
        either setPixels() or setPixelRef() was called.

        @param bitmap  SkBitmap containing SkImageInfo as input, and
                       SkPixelRef as output
        @return        true if SkPixelRef was allocated

        @example       https://fiddle.skia.org/c/@Bitmap_000
    */
    bool allocPixelRef(SkBitmap* bitmap) override;

There are still around 200 disabled examples that need to be fixed
(these result from API changes since the author left).

Change-Id: I14a31348a9ccaaa31f65424b91e3a3533d2583a7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/198824
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
2019-03-15 15:19:18 +00:00

21 lines
754 B
C++

// 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 "fiddle/examples.h"
// HASH=2973b05bfbb6b4c29332c8ac4fcf3995
REG_FIDDLE(Paint_117, 256, 256, true, 0) {
void draw(SkCanvas* canvas) {
auto debugster = [](const char* prefix, const SkPaint& p) -> void {
SkDebugf("%s nothing to draw: %s\n", prefix,
p.nothingToDraw() ? "true" : "false");
};
SkPaint paint;
debugster("initial", paint);
paint.setBlendMode(SkBlendMode::kDst);
debugster("blend dst", paint);
paint.setBlendMode(SkBlendMode::kSrcOver);
debugster("blend src over", paint);
paint.setAlpha(0);
debugster("alpha 0", paint);
}
} // END FIDDLE