1/*
2 * Copyright 2018 Google Inc.
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 "include/core/SkColorSpace.h"
9#include "include/third_party/skcms/skcms.h"
10#include "src/core/SkColorSpaceXformSteps.h"
11#include "tests/Test.h"
12
13DEF_TEST(SkColorSpaceXformSteps_vs_skcms, r) {
14    auto srgb = SkColorSpace::MakeSRGB();
15    auto dp3  = SkColorSpace::MakeRGB(SkNamedTransferFn::kSRGB, SkNamedGamut::kDisplayP3);
16
17    skcms_ICCProfile srgb_profile;
18    srgb->toProfile(&srgb_profile);
19    skcms_ICCProfile dp3_profile;
20    dp3->toProfile(&dp3_profile);
21
22    // These colors provide a good spread of interesting test cases.
23    SkColor colors[] = {
24        0xffff0000, 0x7fff0000, 0x7f7f0000,
25        0xff00ff00, 0x7f00ff00, 0x7f007f00,
26    };
27
28    for (auto color : colors) {
29        auto bgra = skcms_PixelFormat_BGRA_8888,
30              f32 = skcms_PixelFormat_RGBA_ffff;
31        auto unpremul = skcms_AlphaFormat_Unpremul,
32               premul = skcms_AlphaFormat_PremulAsEncoded;
33
34        float via_skcms[4];
35        skcms_Transform(&color,     bgra, unpremul, &srgb_profile,
36                        &via_skcms,  f32,   premul,  &dp3_profile,
37                        1);
38
39        SkColorSpaceXformSteps steps(srgb.get(), kUnpremul_SkAlphaType,
40                                      dp3.get(),   kPremul_SkAlphaType);
41        float via_steps[4] = {
42            SkColorGetR(color) * (1 / 255.0f),
43            SkColorGetG(color) * (1 / 255.0f),
44            SkColorGetB(color) * (1 / 255.0f),
45            SkColorGetA(color) * (1 / 255.0f),
46        };
47        steps.apply(via_steps);
48
49        REPORTER_ASSERT(r, fabsf(via_skcms[0] - via_steps[0]) <= 0.005f);
50        REPORTER_ASSERT(r, fabsf(via_skcms[1] - via_steps[1]) <= 0.005f);
51        REPORTER_ASSERT(r, fabsf(via_skcms[2] - via_steps[2]) <= 0.005f);
52        REPORTER_ASSERT(r, fabsf(via_skcms[3] - via_steps[3]) <= 0.0f);
53
54        // Now go back using the other method's inverse transform
55        float steps_to_skcms[4];
56        skcms_Transform(via_steps,      f32, premul, &dp3_profile,
57                        steps_to_skcms, f32, premul, &srgb_profile,
58                        1);
59
60        float skcms_to_steps[4] = { via_skcms[0], via_skcms[1], via_skcms[2], via_skcms[3] };
61        SkColorSpaceXformSteps inv_steps(dp3.get(), kPremul_SkAlphaType,
62                                        srgb.get(), kPremul_SkAlphaType);
63        inv_steps.apply(skcms_to_steps);
64
65        REPORTER_ASSERT(r, fabsf(skcms_to_steps[0] - steps_to_skcms[0]) <= 0.005f);
66        REPORTER_ASSERT(r, fabsf(skcms_to_steps[1] - steps_to_skcms[1]) <= 0.005f);
67        REPORTER_ASSERT(r, fabsf(skcms_to_steps[2] - steps_to_skcms[2]) <= 0.005f);
68        REPORTER_ASSERT(r, fabsf(skcms_to_steps[3] - steps_to_skcms[3]) <= 0.0f);
69    }
70}
71