1/*
2 * Copyright 2014 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 "SkBitmap.h"
9#include "SkData.h"
10#include "SkEndian.h"
11#include "SkImageInfo.h"
12#include "SkTextureCompressor.h"
13#include "Test.h"
14
15static const int kLATCBlockDimension = 4;
16static const int kLATCEncodedBlockSize = 8;
17
18/**
19 * Make sure that we properly fail when we don't have multiple of four image dimensions.
20 */
21DEF_TEST(CompressLATCFailDimensions, reporter) {
22    SkBitmap bitmap;
23    static const int kWidth = 63;
24    static const int kHeight = 63;
25    SkImageInfo info = SkImageInfo::MakeA8(kWidth, kHeight);
26    REPORTER_ASSERT(reporter, kWidth % kLATCBlockDimension != 0);
27    REPORTER_ASSERT(reporter, kHeight % kLATCBlockDimension != 0);
28
29    bool setInfoSuccess = bitmap.setInfo(info);
30    REPORTER_ASSERT(reporter, setInfoSuccess);
31
32    bool allocPixelsSuccess = bitmap.allocPixels(info);
33    REPORTER_ASSERT(reporter, allocPixelsSuccess);
34    bitmap.unlockPixels();
35
36    const SkTextureCompressor::Format kLATCFormat = SkTextureCompressor::kLATC_Format;
37    SkAutoDataUnref latcData(SkTextureCompressor::CompressBitmapToFormat(bitmap, kLATCFormat));
38    REPORTER_ASSERT(reporter, NULL == latcData);
39}
40
41/**
42 * Make sure that we properly fail when we don't have the correct bitmap type.
43 * LATC compressed textures can only be created from A8 bitmaps.
44 */
45DEF_TEST(CompressLATCFailColorType, reporter) {
46    SkBitmap bitmap;
47    static const int kWidth = 64;
48    static const int kHeight = 64;
49    SkImageInfo info = SkImageInfo::MakeN32Premul(kWidth, kHeight);
50    REPORTER_ASSERT(reporter, kWidth % kLATCBlockDimension == 0);
51    REPORTER_ASSERT(reporter, kHeight % kLATCBlockDimension == 0);
52
53    bool setInfoSuccess = bitmap.setInfo(info);
54    REPORTER_ASSERT(reporter, setInfoSuccess);
55
56    bool allocPixelsSuccess = bitmap.allocPixels(info);
57    REPORTER_ASSERT(reporter, allocPixelsSuccess);
58    bitmap.unlockPixels();
59
60    const SkTextureCompressor::Format kLATCFormat = SkTextureCompressor::kLATC_Format;
61    SkAutoDataUnref latcData(SkTextureCompressor::CompressBitmapToFormat(bitmap, kLATCFormat));
62    REPORTER_ASSERT(reporter, NULL == latcData);
63}
64
65/**
66 * Make sure that if we pass in a solid color bitmap that we get the appropriate results
67 */
68DEF_TEST(CompressLATC, reporter) {
69    SkBitmap bitmap;
70    static const int kWidth = 8;
71    static const int kHeight = 8;
72    SkImageInfo info = SkImageInfo::MakeA8(kWidth, kHeight);
73
74    bool setInfoSuccess = bitmap.setInfo(info);
75    REPORTER_ASSERT(reporter, setInfoSuccess);
76
77    bool allocPixelsSuccess = bitmap.allocPixels(info);
78    REPORTER_ASSERT(reporter, allocPixelsSuccess);
79    bitmap.unlockPixels();
80
81    REPORTER_ASSERT(reporter, kWidth % kLATCBlockDimension == 0);
82    REPORTER_ASSERT(reporter, kHeight % kLATCBlockDimension == 0);
83    const int numBlocks = (kWidth / kLATCBlockDimension) * (kHeight / kLATCBlockDimension);
84    const size_t kSizeToBe = static_cast<size_t>(kLATCEncodedBlockSize * numBlocks);
85
86    for (int lum = 0; lum < 256; ++lum) {
87        bitmap.lockPixels();
88        uint8_t* pixels = reinterpret_cast<uint8_t*>(bitmap.getPixels());
89        REPORTER_ASSERT(reporter, NULL != pixels);
90
91        for (int i = 0; i < kWidth*kHeight; ++i) {
92            pixels[i] = lum;
93        }
94        bitmap.unlockPixels();
95
96        const SkTextureCompressor::Format kLATCFormat = SkTextureCompressor::kLATC_Format;
97        SkAutoDataUnref latcData(
98            SkTextureCompressor::CompressBitmapToFormat(bitmap, kLATCFormat));
99        REPORTER_ASSERT(reporter, NULL != latcData);
100        REPORTER_ASSERT(reporter, kSizeToBe == latcData->size());
101
102        // Make sure that it all matches a given block encoding. If the entire bitmap
103        // is a single value, then the lower two bytes of the encoded data should be that
104        // value. The remaining indices can be any value, and since we try to match the pixels
105        // in the chosen palette in increasing index order, each one should be zero. Hence,
106        // the correct encoding should be just the two luminance values in the bottom two
107        // bytes of the block encoding.
108        const uint64_t kConstColorEncoding = SkEndian_SwapLE64(lum | (lum << 8));
109        const uint64_t* blockPtr = reinterpret_cast<const uint64_t*>(latcData->data());
110        for (int i = 0; i < numBlocks; ++i) {
111            REPORTER_ASSERT(reporter, blockPtr[i] == kConstColorEncoding);
112        }
113    }
114}
115