aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/gpu/effects/GrConfigConversionEffect.fp
blob: f466cc7d40763b08e9a1ee2b31a28c76af152d76 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
/*
 * Copyright 2018 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

@header {
    #include "GrClip.h"
    #include "GrContext.h"
    #include "GrContextPriv.h"
    #include "GrProxyProvider.h"
    #include "GrRenderTargetContext.h"
}

@class {
    static bool TestForPreservingPMConversions(GrContext* context) {
        static constexpr int kSize = 256;
        static constexpr GrPixelConfig kConfig = kRGBA_8888_GrPixelConfig;
        SkAutoTMalloc<uint32_t> data(kSize * kSize * 3);
        uint32_t* srcData = data.get();
        uint32_t* firstRead = data.get() + kSize * kSize;
        uint32_t* secondRead = data.get() + 2 * kSize * kSize;

        // Fill with every possible premultiplied A, color channel value. There will be 256-y
        // duplicate values in row y. We set r, g, and b to the same value since they are handled
        // identically.
        for (int y = 0; y < kSize; ++y) {
            for (int x = 0; x < kSize; ++x) {
                uint8_t* color = reinterpret_cast<uint8_t*>(&srcData[kSize*y + x]);
                color[3] = y;
                color[2] = SkTMin(x, y);
                color[1] = SkTMin(x, y);
                color[0] = SkTMin(x, y);
            }
        }
        memset(firstRead, 0, kSize * kSize * sizeof(uint32_t));
        memset(secondRead, 0, kSize * kSize * sizeof(uint32_t));

        const SkImageInfo ii = SkImageInfo::Make(kSize, kSize,
                                                 kRGBA_8888_SkColorType, kPremul_SkAlphaType);

        sk_sp<GrRenderTargetContext> readRTC(
                context->contextPriv().makeDeferredRenderTargetContext(SkBackingFit::kExact,
                                                                       kSize, kSize,
                                                                       kConfig, nullptr));
        sk_sp<GrRenderTargetContext> tempRTC(
                context->contextPriv().makeDeferredRenderTargetContext(SkBackingFit::kExact,
                                                                       kSize, kSize,
                                                                       kConfig, nullptr));
        if (!readRTC || !readRTC->asTextureProxy() || !tempRTC) {
            return false;
        }
        // Adding discard to appease vulkan validation warning about loading uninitialized data on
        // draw
        readRTC->discard();

        GrProxyProvider* proxyProvider = context->contextPriv().proxyProvider();

        SkPixmap pixmap(ii, srcData, 4 * kSize);

        // This function is only ever called if we are in a GrContext that has a GrGpu since we are
        // calling read pixels here. Thus the pixel data will be uploaded immediately and we don't
        // need to keep the pixel data alive in the proxy. Therefore the ReleaseProc is nullptr.
        sk_sp<SkImage> image = SkImage::MakeFromRaster(pixmap, nullptr, nullptr);

        sk_sp<GrTextureProxy> dataProxy = proxyProvider->createTextureProxy(std::move(image),
                                                                            kNone_GrSurfaceFlags,
                                                                            1,
                                                                            SkBudgeted::kYes,
                                                                            SkBackingFit::kExact);
        if (!dataProxy) {
            return false;
        }

        static const SkRect kRect = SkRect::MakeIWH(kSize, kSize);

        // We do a PM->UPM draw from dataTex to readTex and read the data. Then we do a UPM->PM draw
        // from readTex to tempTex followed by a PM->UPM draw to readTex and finally read the data.
        // We then verify that two reads produced the same values.

        GrPaint paint1;
        GrPaint paint2;
        GrPaint paint3;
        std::unique_ptr<GrFragmentProcessor> pmToUPM(
                new GrConfigConversionEffect(PMConversion::kToUnpremul));
        std::unique_ptr<GrFragmentProcessor> upmToPM(
                new GrConfigConversionEffect(PMConversion::kToPremul));

        paint1.addColorTextureProcessor(dataProxy, SkMatrix::I());
        paint1.addColorFragmentProcessor(pmToUPM->clone());
        paint1.setPorterDuffXPFactory(SkBlendMode::kSrc);

        readRTC->fillRectToRect(GrNoClip(), std::move(paint1), GrAA::kNo, SkMatrix::I(), kRect,
                                kRect);
        if (!readRTC->readPixels(ii, firstRead, 0, 0, 0)) {
            return false;
        }

        // Adding discard to appease vulkan validation warning about loading uninitialized data on
        // draw
        tempRTC->discard();

        paint2.addColorTextureProcessor(readRTC->asTextureProxyRef(), SkMatrix::I());
        paint2.addColorFragmentProcessor(std::move(upmToPM));
        paint2.setPorterDuffXPFactory(SkBlendMode::kSrc);

        tempRTC->fillRectToRect(GrNoClip(), std::move(paint2), GrAA::kNo, SkMatrix::I(), kRect,
                                kRect);

        paint3.addColorTextureProcessor(tempRTC->asTextureProxyRef(), SkMatrix::I());
        paint3.addColorFragmentProcessor(std::move(pmToUPM));
        paint3.setPorterDuffXPFactory(SkBlendMode::kSrc);

        readRTC->fillRectToRect(GrNoClip(), std::move(paint3), GrAA::kNo, SkMatrix::I(), kRect,
                                kRect);

        if (!readRTC->readPixels(ii, secondRead, 0, 0, 0)) {
            return false;
        }

        for (int y = 0; y < kSize; ++y) {
            for (int x = 0; x <= y; ++x) {
                if (firstRead[kSize * y + x] != secondRead[kSize * y + x]) {
                    return false;
                }
            }
        }

        return true;
    }
}

@make {
    static std::unique_ptr<GrFragmentProcessor> Make(std::unique_ptr<GrFragmentProcessor> fp,
                                                     PMConversion pmConversion) {
        if (!fp) {
            return nullptr;
        }
        std::unique_ptr<GrFragmentProcessor> ccFP(new GrConfigConversionEffect(pmConversion));
        std::unique_ptr<GrFragmentProcessor> fpPipeline[] = { std::move(fp), std::move(ccFP) };
        return GrFragmentProcessor::RunInSeries(fpPipeline, 2);
    }
}

layout(key) in PMConversion pmConversion;

@emitCode {
    fragBuilder->forceHighPrecision();
}

void main() {
    // Aggressively round to the nearest exact (N / 255) floating point value. This lets us find a
    // round-trip preserving pair on some GPUs that do odd byte to float conversion.
    sk_OutColor = floor(sk_InColor * 255 + 0.5) / 255;

    @switch (pmConversion) {
        case PMConversion::kToPremul:
            sk_OutColor.rgb = floor(sk_OutColor.rgb * sk_OutColor.a * 255 + 0.5) / 255;
            break;

        case PMConversion::kToUnpremul:
            sk_OutColor.rgb = sk_OutColor.a <= 0.0 ?
                                          half3(0) :
                                          floor(sk_OutColor.rgb / sk_OutColor.a * 255 + 0.5) / 255;
            break;
    }
}

@test(data) {
    PMConversion pmConv = static_cast<PMConversion>(data->fRandom->nextULessThan(
                                                             (int) PMConversion::kPMConversionCnt));
    return std::unique_ptr<GrFragmentProcessor>(new GrConfigConversionEffect(pmConv));
}