1/*
2 * Copyright 2016 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 "SkPM4f.h"
9#include "SkRasterPipeline.h"
10#include "SkSRGB.h"
11#include "SkTypes.h"
12#include "Test.h"
13#include <math.h>
14#include "../src/jumper/SkJumper.h"
15
16static uint8_t linear_to_srgb(float l) {
17    return (uint8_t)sk_linear_to_srgb(Sk4f{l})[0];
18}
19
20DEF_TEST(sk_linear_to_srgb, r) {
21    // All bytes should round trip.
22    for (int i = 0; i < 256; i++) {
23        int actual = linear_to_srgb(sk_linear_from_srgb[i]);
24        if (i != actual) {
25            ERRORF(r, "%d -> %d\n", i, actual);
26        }
27    }
28
29    // Should be monotonic between 0 and 1.
30    uint8_t prev = 0;
31    for (float f = FLT_MIN; f <= 1.0f; ) {  // We don't bother checking denorm values.
32        uint8_t srgb = linear_to_srgb(f);
33
34        REPORTER_ASSERT(r, srgb >= prev);
35        prev = srgb;
36
37        union { float flt; uint32_t bits; } pun = { f };
38        pun.bits++;
39        SkDEBUGCODE(pun.bits += 127);
40        f = pun.flt;
41    }
42}
43
44DEF_TEST(sk_pipeline_srgb_roundtrip, r) {
45    uint32_t reds[256];
46    for (int i = 0; i < 256; i++) {
47        reds[i] = i;
48    }
49
50    SkJumper_MemoryCtx ptr = { reds, 0 };
51
52    SkRasterPipeline_<256> p;
53    p.append(SkRasterPipeline::load_8888,  &ptr);
54    p.append(SkRasterPipeline::from_srgb);
55    p.append(SkRasterPipeline::to_srgb);
56    p.append(SkRasterPipeline::store_8888, &ptr);
57
58    p.run(0,0,256,1);
59
60    for (int i = 0; i < 256; i++) {
61        if (reds[i] != (uint32_t)i) {
62            ERRORF(r, "%d doesn't round trip, %d", i, reds[i]);
63        }
64    }
65}
66
67DEF_TEST(sk_pipeline_srgb_edge_cases, r) {
68    // We need to run at least 4 pixels to make sure we hit all specializations.
69    SkPM4f colors[4] = { {{0,1,1,1}}, {{0,0,0,0}}, {{0,0,0,0}}, {{0,0,0,0}} };
70    auto& color = colors[0];
71
72    SkJumper_MemoryCtx dst = { &color, 0 };
73
74    SkSTArenaAlloc<256> alloc;
75    SkRasterPipeline p(&alloc);
76    p.append_constant_color(&alloc, color);
77    p.append(SkRasterPipeline::to_srgb);
78    p.append(SkRasterPipeline::store_f32, &dst);
79    p.run(0,0,4,1);
80
81    if (color.r() != 0.0f) {
82        ERRORF(r, "expected to_srgb() to map 0.0f to 0.0f, got %f", color.r());
83    }
84    if (color.g() != 1.0f) {
85        float f = color.g();
86        uint32_t x;
87        memcpy(&x, &f, 4);
88        ERRORF(r, "expected to_srgb() to map 1.0f to 1.0f, got %f (%08x)", color.g(), x);
89    }
90}
91