1/*
2 * Copyright 2021 Google LLC
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "gm/gm.h"
9#include "include/core/SkBitmap.h"
10#include "include/core/SkCanvas.h"
11#include "include/core/SkPaint.h"
12#include "include/core/SkSize.h"
13#include "include/core/SkSurface.h"
14#include "include/effects/SkRuntimeEffect.h"
15#include "src/gpu/GrCaps.h"
16#include "src/gpu/GrDirectContextPriv.h"
17#include "tests/Test.h"
18#include "tools/Resources.h"
19#include "tools/RuntimeBlendUtils.h"
20#include "tools/ToolUtils.h"
21
22static bool nearly_equal(const SkColor& x, const SkColor& y) {
23    const int kTolerance = 1;
24    return abs((int)SkColorGetA(x) - (int)SkColorGetA(y)) <= kTolerance &&
25           abs((int)SkColorGetR(x) - (int)SkColorGetR(y)) <= kTolerance &&
26           abs((int)SkColorGetG(x) - (int)SkColorGetG(y)) <= kTolerance &&
27           abs((int)SkColorGetB(x) - (int)SkColorGetB(y)) <= kTolerance;
28}
29
30static void test_blend(skiatest::Reporter* r, SkSurface* surface) {
31    SkBitmap bitmap;
32    REPORTER_ASSERT(r, bitmap.tryAllocPixels(surface->imageInfo()));
33
34    for (int m = 0; m <= (int)SkBlendMode::kLastMode; ++m) {
35        SkBlendMode mode = (SkBlendMode)m;
36        for (int alpha : {0x80, 0xFF}) {
37            std::vector<SkColor> colors;
38            for (bool useRuntimeBlend : {false, true}) {
39                // Draw a solid red pixel.
40                SkPaint paint;
41                paint.setColor(SK_ColorRED);
42                paint.setBlendMode(SkBlendMode::kSrc);
43                surface->getCanvas()->drawRect(SkRect::MakeWH(1, 1), paint);
44
45                // Draw a blue pixel on top of it, using the passed-in blend mode.
46                paint.setColor(SkColorSetARGB(alpha, 0x00, 0x00, 0xFF));
47                if (useRuntimeBlend) {
48                    paint.setBlender(GetRuntimeBlendForBlendMode(mode));
49                } else {
50                    paint.setBlendMode(mode);
51                }
52                surface->getCanvas()->drawRect(SkRect::MakeWH(1, 1), paint);
53
54                // Read back the red/blue blended pixel.
55                REPORTER_ASSERT(r, surface->readPixels(bitmap.info(), bitmap.getPixels(),
56                                                       bitmap.rowBytes(), /*srcX=*/0, /*srcY=*/0));
57                colors.push_back(bitmap.getColor(/*x=*/0, /*y=*/0));
58            }
59
60            REPORTER_ASSERT(r, nearly_equal(colors[0], colors[1]),
61                            "Expected: %s %s blend matches. Actual: Built-in "
62                            "A=%02X R=%02X G=%02X B=%02X, Runtime A=%02X R=%02X G=%02X B=%02X",
63                            SkBlendMode_Name(mode),
64                            (alpha == 0xFF) ? "solid" : "transparent",
65                            SkColorGetA(colors[0]),
66                            SkColorGetR(colors[0]),
67                            SkColorGetG(colors[0]),
68                            SkColorGetB(colors[0]),
69                            SkColorGetA(colors[1]),
70                            SkColorGetR(colors[1]),
71                            SkColorGetG(colors[1]),
72                            SkColorGetB(colors[1]));
73        }
74    }
75}
76
77DEF_TEST(SkRuntimeBlender_CPU, r) {
78    const SkImageInfo info = SkImageInfo::MakeN32Premul(/*width=*/1, /*height=*/1);
79    sk_sp<SkSurface> surface(SkSurface::MakeRaster(info));
80
81    test_blend(r, surface.get());
82}
83
84DEF_GPUTEST_FOR_RENDERING_CONTEXTS(SkRuntimeBlender_GPU, r, ctxInfo) {
85    const SkImageInfo info = SkImageInfo::MakeN32Premul(/*width=*/1, /*height=*/1);
86    sk_sp<SkSurface> surface(SkSurface::MakeRenderTarget(ctxInfo.directContext(),
87                                                         SkBudgeted::kNo, info));
88    test_blend(r, surface.get());
89}
90