Add initial pipeline for decompressors

tests/TextureCompressionTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkData.h"
 #include "SkEndian.h"
@@ skipping 57 matching lines @@
     bitmap.unlockPixels();
 
     for (int i = 0; i < SkTextureCompressor::kFormatCnt; ++i) {
         const SkTextureCompressor::Format fmt = static_cast<SkTextureCompressor::Format>(i);
         SkAutoDataUnref data(SkTextureCompressor::CompressBitmapToFormat(bitmap, fmt));
         REPORTER_ASSERT(reporter, NULL == data);
     }
 }
 
 /**
+ * Make sure that if you compress a texture with alternating black/white pixels, and
+ * then decompress it, you get what you started with.
+ */
+DEF_TEST(CompressCheckerboard, reporter) {
+    SkBitmap bitmap;
+    static const int kWidth = 12;
+    static const int kHeight = 12;
+    SkImageInfo info = SkImageInfo::MakeA8(kWidth, kHeight);
+
+    // ASTC is at most 12x12, and any dimension divisible by 12 is also divisible
+    // by 4, which is the dimensions of R11_EAC and LATC. In the future, we might
+    // support additional variants of ASTC, such as 5x6 and 8x8, in which case this would
+    // need to be updated.
+    REPORTER_ASSERT(reporter, kWidth % 12 == 0);
+    REPORTER_ASSERT(reporter, kHeight % 12 == 0);
+
+    bool setInfoSuccess = bitmap.setInfo(info);
+    REPORTER_ASSERT(reporter, setInfoSuccess);
+
+    bool allocPixelsSuccess = bitmap.allocPixels(info);
+    REPORTER_ASSERT(reporter, allocPixelsSuccess);
+
+    bitmap.lockPixels();
+    uint8_t* pixels = reinterpret_cast<uint8_t*>(bitmap.getPixels());
+    REPORTER_ASSERT(reporter, NULL != pixels);
+
+    for (int y = 0; y < kHeight; ++y) {
+        for (int x = 0; x < kWidth; ++x) {
+            if ((x ^ y) & 1) {
+                pixels[x] = 0xFF;
+            } else {
+                pixels[x] = 0;
+            }
+        }
+        pixels += bitmap.rowBytes();
+    }
+    bitmap.unlockPixels();
+

[robertphillips, 2014/07/31 15:01:02]

SkAutoMalloc ?

[krajcevski, 2014/07/31 15:12:19]

Done.

+    uint8_t* decompBuffer = reinterpret_cast<uint8_t*>(sk_malloc_throw(kWidth*kHeight));
+    REPORTER_ASSERT(reporter, NULL != decompBuffer);
+    if (NULL == decompBuffer) {
+        return;
+    }
+
+    for (int i = 0; i < SkTextureCompressor::kFormatCnt; ++i) {
+        const SkTextureCompressor::Format fmt = static_cast<SkTextureCompressor::Format>(i);
+
+        // ASTC is for RGBA data, and doesn't fit the paradigm of this test.

[robertphillips, 2014/07/31 15:01:02]

// TODO: add ASTC decompression test (when ASTC decompression is added) ?

[krajcevski, 2014/07/31 15:12:19]

Done.

+        if (SkTextureCompressor::kASTC_12x12_Format == fmt) {
+            continue;
+        }
+
+        SkAutoDataUnref data(SkTextureCompressor::CompressBitmapToFormat(bitmap, fmt));
+        REPORTER_ASSERT(reporter, NULL != data);
+
+        bool decompResult = SkTextureCompressor::DecompressBufferFromFormat(

[robertphillips, 2014/07/31 15:01:02]

tab these guys over a bit (and maybe split across 2 lines) ?

[krajcevski, 2014/07/31 15:12:18]

Done.

+            decompBuffer, kWidth, data->bytes(), kWidth, kHeight, fmt);
+        REPORTER_ASSERT(reporter, decompResult);
+
+        bitmap.lockPixels();
+        pixels = reinterpret_cast<uint8_t*>(bitmap.getPixels());
+        REPORTER_ASSERT(reporter, NULL != pixels);
+
+        for (int y = 0; y < kHeight; ++y) {
+            for (int x = 0; x < kWidth; ++x) {
+                bool ok = pixels[y*bitmap.rowBytes() + x] == decompBuffer[y*kWidth + x];
+                REPORTER_ASSERT(reporter, ok);
+            }
+        }
+    }
+
+    sk_free(decompBuffer);
+}
+
+/**
  * Make sure that if we pass in a solid color bitmap that we get the appropriate results
  */
 DEF_TEST(CompressLATC, reporter) {
 
     const SkTextureCompressor::Format kLATCFormat = SkTextureCompressor::kLATC_Format;
     static const int kLATCEncodedBlockSize = 8;
 
     SkBitmap bitmap;
     static const int kWidth = 8;
     static const int kHeight = 8;
@@ skipping 46 matching lines @@
                 (kIndex << 28) | (kIndex << 31) | (kIndex << 34) | (kIndex << 37) |
                 (kIndex << 40) | (kIndex << 43) | (kIndex << 46) | (kIndex << 49) |
                 (kIndex << 52) | (kIndex << 55) | (kIndex << 58) | (kIndex << 61));
 
         const uint64_t* blockPtr = reinterpret_cast<const uint64_t*>(latcData->data());
         for (size_t i = 0; i < (kSizeToBe/8); ++i) {
             REPORTER_ASSERT(reporter, blockPtr[i] == kConstColorEncoding);
         }
     }
 }