skia2/tests/ColorMatrixTest.cpp
Mike Reed b286bc2da8 Introduce new factory for SkColorFilters
Idea: transition callers to this, so we can later typedef SkColorFilter
and SkShader to the same thing.

Bug: skia:8937
Change-Id: I000c882e11622091aa44c141aa6ddd1216414f46
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/206685
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2019-04-08 21:03:59 +00:00

124 lines
4.2 KiB
C++

/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkBitmap.h"
#include "SkCanvas.h"
#include "SkColor.h"
#include "SkColorFilter.h"
#include "SkPaint.h"
#include "SkRefCnt.h"
#include "SkScalar.h"
#include "Test.h"
#include <cmath>
#include <cstdlib>
static inline void assert_color(skiatest::Reporter* reporter,
SkColor expected, SkColor actual, int tolerance) {
REPORTER_ASSERT(reporter, abs((int)(SkColorGetA(expected) - SkColorGetA(actual))) <= tolerance);
REPORTER_ASSERT(reporter, abs((int)(SkColorGetR(expected) - SkColorGetR(actual))) <= tolerance);
REPORTER_ASSERT(reporter, abs((int)(SkColorGetG(expected) - SkColorGetG(actual))) <= tolerance);
REPORTER_ASSERT(reporter, abs((int)(SkColorGetB(expected) - SkColorGetB(actual))) <= tolerance);
}
static inline void assert_color(skiatest::Reporter* reporter, SkColor expected, SkColor actual) {
const int TOLERANCE = 1;
assert_color(reporter, expected, actual, TOLERANCE);
}
/**
* This test case is a mirror of the Android CTS tests for MatrixColorFilter
* found in the android.graphics.ColorMatrixColorFilterTest class.
*/
static inline void test_colorMatrixCTS(skiatest::Reporter* reporter) {
SkBitmap bitmap;
bitmap.allocN32Pixels(1,1);
SkCanvas canvas(bitmap);
SkPaint paint;
SkScalar blueToCyan[20] = {
1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
0.0f, 1.0f, 1.0f, 0.0f, 0.0f,
0.0f, 0.0f, 1.0f, 0.0f, 0.0f,
0.0f, 0.0f, 0.0f, 1.0f, 0.0f };
paint.setColorFilter(SkColorFilters::MatrixRowMajor255(blueToCyan));
paint.setColor(SK_ColorBLUE);
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SK_ColorCYAN, bitmap.getColor(0, 0));
paint.setColor(SK_ColorGREEN);
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SK_ColorGREEN, bitmap.getColor(0, 0));
paint.setColor(SK_ColorRED);
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SK_ColorRED, bitmap.getColor(0, 0));
// color components are clipped, not scaled
paint.setColor(SK_ColorMAGENTA);
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SK_ColorWHITE, bitmap.getColor(0, 0));
SkScalar transparentRedAddBlue[20] = {
1.0f, 0.0f, 0.0f, 0.0f, 0.0f,
0.0f, 1.0f, 0.0f, 0.0f, 0.0f,
0.0f, 0.0f, 1.0f, 0.0f, 64.0f,
-0.5f, 0.0f, 0.0f, 1.0f, 0.0f
};
paint.setColorFilter(SkColorFilters::MatrixRowMajor255(transparentRedAddBlue));
bitmap.eraseColor(SK_ColorTRANSPARENT);
paint.setColor(SK_ColorRED);
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SkColorSetARGB(128, 255, 0, 64), bitmap.getColor(0, 0), 2);
paint.setColor(SK_ColorCYAN);
canvas.drawPoint(0, 0, paint);
// blue gets clipped
assert_color(reporter, SK_ColorCYAN, bitmap.getColor(0, 0));
// change array to filter out green
REPORTER_ASSERT(reporter, 1.0f == transparentRedAddBlue[6]);
transparentRedAddBlue[6] = 0.0f;
// check that changing the array has no effect
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SK_ColorCYAN, bitmap.getColor(0, 0));
// create a new filter with the changed matrix
paint.setColorFilter(SkColorFilters::MatrixRowMajor255(transparentRedAddBlue));
canvas.drawPoint(0, 0, paint);
assert_color(reporter, SK_ColorBLUE, bitmap.getColor(0, 0));
}
DEF_TEST(ColorMatrix, reporter) {
test_colorMatrixCTS(reporter);
}
DEF_TEST(ColorMatrix_clamp_while_unpremul, r) {
// This matrix does green += 255/255 and alpha += 32/255. We want to test
// that if we pass it opaque alpha and small red and blue values, red and
// blue stay unchanged, not pumped up by that ~1.12 intermediate alpha.
SkScalar m[] = {
1, 0, 0, 0, 0,
0, 1, 0, 0, 255,
0, 0, 1, 0, 0,
0, 0, 0, 1, 32,
};
auto filter = SkColorFilters::MatrixRowMajor255(m);
SkColor filtered = filter->filterColor(0xff0a0b0c);
REPORTER_ASSERT(r, SkColorGetA(filtered) == 0xff);
REPORTER_ASSERT(r, SkColorGetR(filtered) == 0x0a);
REPORTER_ASSERT(r, SkColorGetG(filtered) == 0xff);
REPORTER_ASSERT(r, SkColorGetB(filtered) == 0x0c);
}