Revert "Remove compressed (ETC1) texture support from Ganesh"

This reverts commit ee26363aaae62db2a851f2873e2405a9cf7f995a.

Reason for revert: Failing Google 3 roll.

Original change's description:
> Remove compressed (ETC1) texture support from Ganesh
> 
> Change-Id: If4cf286df87ea87338aba47001d90a5fcc4f2667
> Reviewed-on: https://skia-review.googlesource.com/17456
> Commit-Queue: Robert Phillips <robertphillips@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> 

TBR=bsalomon@google.com,robertphillips@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: Ie1a57187287e03600a69e374501478e93c41415c
Reviewed-on: https://skia-review.googlesource.com/17527
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>

2 files changed, 101 insertions, 1 deletions

diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index 4dc776734e..2fb367d66f 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -45,6 +45,7 @@ public:
     bool srgbWriteControl() const { return fSRGBWriteControl; }
     bool discardRenderTargetSupport() const { return fDiscardRenderTargetSupport; }
     bool gpuTracingSupport() const { return fGpuTracingSupport; }
+    bool compressedTexSubImageSupport() const { return fCompressedTexSubImageSupport; }
     bool oversizedStencilSupport() const { return fOversizedStencilSupport; }
     bool textureBarrierSupport() const { return fTextureBarrierSupport; }
     bool sampleLocationsSupport() const { return fSampleLocationsSupport; }
@@ -211,6 +212,7 @@ protected:
     bool fReuseScratchTextures                       : 1;
     bool fReuseScratchBuffers                        : 1;
     bool fGpuTracingSupport                          : 1;
+    bool fCompressedTexSubImageSupport               : 1;
     bool fOversizedStencilSupport                    : 1;
     bool fTextureBarrierSupport                      : 1;
     bool fSampleLocationsSupport                     : 1;
diff --git a/include/gpu/GrTypes.h b/include/gpu/GrTypes.h
index e9630270f6..1619b9afa4 100644
--- a/include/gpu/GrTypes.h
+++ b/include/gpu/GrTypes.h
@@ -298,7 +298,10 @@ enum GrPixelConfig {
      * 8 bit signed integers per-channel. Byte order is b,g,r,a.
      */
     kRGBA_8888_sint_GrPixelConfig,
-
+    /**
+     * ETC1 Compressed Data
+     */
+    kETC1_GrPixelConfig,
     /**
      * Byte order is r, g, b, a.  This color format is 32 bits per channel
      */
@@ -334,6 +337,58 @@ static const int kGrPixelConfigCnt = kLast_GrPixelConfig + 1;
     #error "SK_*32_SHIFT values must correspond to GL_BGRA or GL_RGBA format."
 #endif
 
+// Returns true if the pixel config is a GPU-specific compressed format
+// representation.
+static inline bool GrPixelConfigIsCompressed(GrPixelConfig config) {
+    switch (config) {
+        case kETC1_GrPixelConfig:
+            return true;
+        case kUnknown_GrPixelConfig:
+        case kAlpha_8_GrPixelConfig:
+        case kGray_8_GrPixelConfig:
+        case kRGB_565_GrPixelConfig:
+        case kRGBA_4444_GrPixelConfig:
+        case kRGBA_8888_GrPixelConfig:
+        case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
+        case kRGBA_8888_sint_GrPixelConfig:
+        case kRGBA_float_GrPixelConfig:
+        case kRG_float_GrPixelConfig:
+        case kAlpha_half_GrPixelConfig:
+        case kRGBA_half_GrPixelConfig:
+            return false;
+    }
+    SkFAIL("Invalid pixel config");
+    return false;
+}
+
+/** If the pixel config is compressed, return an equivalent uncompressed format. */
+static inline GrPixelConfig GrMakePixelConfigUncompressed(GrPixelConfig config) {
+    switch (config) {
+        case kETC1_GrPixelConfig:
+            return kRGBA_8888_GrPixelConfig;
+        case kUnknown_GrPixelConfig:
+        case kAlpha_8_GrPixelConfig:
+        case kGray_8_GrPixelConfig:
+        case kRGB_565_GrPixelConfig:
+        case kRGBA_4444_GrPixelConfig:
+        case kRGBA_8888_GrPixelConfig:
+        case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
+        case kRGBA_8888_sint_GrPixelConfig:
+        case kRGBA_float_GrPixelConfig:
+        case kRG_float_GrPixelConfig:
+        case kAlpha_half_GrPixelConfig:
+        case kRGBA_half_GrPixelConfig:
+            SkASSERT(!GrPixelConfigIsCompressed(config));
+            return config;
+    }
+    SkFAIL("Invalid pixel config");
+    return config;
+}
+
 // Returns true if the pixel config is 32 bits per pixel
 static inline bool GrPixelConfigIs8888Unorm(GrPixelConfig config) {
     switch (config) {
@@ -348,6 +403,7 @@ static inline bool GrPixelConfigIs8888Unorm(GrPixelConfig config) {
         case kRGB_565_GrPixelConfig:
         case kRGBA_4444_GrPixelConfig:
         case kRGBA_8888_sint_GrPixelConfig:
+        case kETC1_GrPixelConfig:
         case kRGBA_float_GrPixelConfig:
         case kRG_float_GrPixelConfig:
         case kAlpha_half_GrPixelConfig:
@@ -373,6 +429,7 @@ static inline bool GrPixelConfigIsSRGB(GrPixelConfig config) {
         case kRGBA_8888_GrPixelConfig:
         case kBGRA_8888_GrPixelConfig:
         case kRGBA_8888_sint_GrPixelConfig:
+        case kETC1_GrPixelConfig:
         case kRGBA_float_GrPixelConfig:
         case kRG_float_GrPixelConfig:
         case kAlpha_half_GrPixelConfig:
@@ -401,6 +458,7 @@ static inline GrPixelConfig GrPixelConfigSwapRAndB(GrPixelConfig config) {
         case kRGB_565_GrPixelConfig:
         case kRGBA_4444_GrPixelConfig:
         case kRGBA_8888_sint_GrPixelConfig:
+        case kETC1_GrPixelConfig:
         case kRGBA_float_GrPixelConfig:
         case kRG_float_GrPixelConfig:
         case kAlpha_half_GrPixelConfig:
@@ -412,6 +470,7 @@ static inline GrPixelConfig GrPixelConfigSwapRAndB(GrPixelConfig config) {
 }
 
 static inline size_t GrBytesPerPixel(GrPixelConfig config) {
+    SkASSERT(!GrPixelConfigIsCompressed(config));
     switch (config) {
         case kAlpha_8_GrPixelConfig:
         case kGray_8_GrPixelConfig:
@@ -433,6 +492,7 @@ static inline size_t GrBytesPerPixel(GrPixelConfig config) {
         case kRG_float_GrPixelConfig:
             return 8;
         case kUnknown_GrPixelConfig:
+        case kETC1_GrPixelConfig:
             return 0;
     }
     SkFAIL("Invalid pixel config");
@@ -441,6 +501,7 @@ static inline size_t GrBytesPerPixel(GrPixelConfig config) {
 
 static inline bool GrPixelConfigIsOpaque(GrPixelConfig config) {
     switch (config) {
+        case kETC1_GrPixelConfig:
         case kRGB_565_GrPixelConfig:
         case kGray_8_GrPixelConfig:
             return true;
@@ -476,6 +537,7 @@ static inline bool GrPixelConfigIsAlphaOnly(GrPixelConfig config) {
         case kSRGBA_8888_GrPixelConfig:
         case kSBGRA_8888_GrPixelConfig:
         case kRGBA_8888_sint_GrPixelConfig:
+        case kETC1_GrPixelConfig:
         case kRGBA_float_GrPixelConfig:
         case kRG_float_GrPixelConfig:
         case kRGBA_half_GrPixelConfig:
@@ -502,6 +564,7 @@ static inline bool GrPixelConfigIsFloatingPoint(GrPixelConfig config) {
         case kSRGBA_8888_GrPixelConfig:
         case kSBGRA_8888_GrPixelConfig:
         case kRGBA_8888_sint_GrPixelConfig:
+        case kETC1_GrPixelConfig:
             return false;
     }
     SkFAIL("Invalid pixel config");
@@ -717,6 +780,41 @@ enum GrGLBackendState {
 };
 
 /**
+ * Returns the data size for the given compressed pixel config
+ */
+static inline size_t GrCompressedFormatDataSize(GrPixelConfig config,
+                                                int width, int height) {
+    SkASSERT(GrPixelConfigIsCompressed(config));
+
+    switch (config) {
+        case kETC1_GrPixelConfig:
+            SkASSERT((width & 3) == 0);
+            SkASSERT((height & 3) == 0);
+            return (width >> 2) * (height >> 2) * 8;
+
+        case kUnknown_GrPixelConfig:
+        case kAlpha_8_GrPixelConfig:
+        case kGray_8_GrPixelConfig:
+        case kRGB_565_GrPixelConfig:
+        case kRGBA_4444_GrPixelConfig:
+        case kRGBA_8888_GrPixelConfig:
+        case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
+        case kRGBA_8888_sint_GrPixelConfig:
+        case kRGBA_float_GrPixelConfig:
+        case kRG_float_GrPixelConfig:
+        case kAlpha_half_GrPixelConfig:
+        case kRGBA_half_GrPixelConfig:
+            SkFAIL("Unknown compressed pixel config");
+            return 4 * width * height;
+    }
+
+    SkFAIL("Invalid pixel config");
+    return 4 * width * height;
+}
+
+/**
  * This value translates to reseting all the context state for any backend.
  */
 static const uint32_t kAll_GrBackendState = 0xffffffff;