Initial work to get ETC1 data up to the GPU

src/gpu/SkGr.cpp

Index: src/gpu/SkGr.cpp
diff --git a/src/gpu/SkGr.cpp b/src/gpu/SkGr.cpp
index 6bd04dec3a841ac8186b8644ab212aca6512fba8..4e18b3d2042ab4b9e6a567c5c4e6e1e362aff00e 100644
--- a/src/gpu/SkGr.cpp
+++ b/src/gpu/SkGr.cpp
@@ -8,9 +8,14 @@
 #include "SkGr.h"
 #include "SkColorFilter.h"
 #include "SkConfig8888.h"
+#include "SkData.h"
 #include "SkMessageBus.h"
 #include "SkPixelRef.h"
 #include "GrResourceCache.h"
+#include "GrGpu.h"
+#include "GrDrawTargetCaps.h"
+
+#include "etc1.h"
 
 /*  Fill out buffer with the compressed format Ganesh expects from a colortable
  based bitmap. [palette (colortable) + indices].
@@ -172,6 +177,46 @@ static GrTexture* sk_gr_create_bitmap_texture(GrContext* ctx,
             bitmap = &tmpBitmap;
             desc.fConfig = SkImageInfo2GrPixelConfig(bitmap->info());
         }
+    } else if (cache && ctx->getGpu()->caps()->isConfigTexturable(kETC1_GrPixelConfig)) {
+        SkData *data = bitmap->pixelRef()->refEncodedData();

[robertphillips, 2014/05/30 15:00:22]

What do you think about making this a static function (e.g.,
create_etc1_texture) and using it like:
   GrTexture* result = create_etc1_texture(desc, params, bitmap);
   if (NULL != result) {
       return result;
   }

?

[krajcevski, 2014/05/30 16:21:50]

Sounds good to me.

Done.

+        do {
+            // Is this even encoded data?
+            if (NULL == data) {
+                break;
+            }
+
+            // Is this a valid PKM encoded data?
+            const uint8_t *bytes = data->bytes();
+            if (!etc1_pkm_is_valid(bytes)) {
+                break;
+            }
+
+            uint32_t encodedWidth = etc1_pkm_get_width(bytes);
+            uint32_t encodedHeight = etc1_pkm_get_height(bytes);
+
+            // Does the data match the dimensions of the bitmap? If not,
+            // then we don't know how to scale the image to match it...
+            if (encodedWidth != static_cast<uint32_t>(bitmap->width()) ||
+                encodedHeight != static_cast<uint32_t>(bitmap->height())) {
+                break;
+            }
+
+            // Everything seems good... skip ahead to the data.
+            bytes += ETC_PKM_HEADER_SIZE;
+            desc.fConfig = kETC1_GrPixelConfig;
+
+            // This texture is likely to be used again so leave it in the cache
+            GrCacheID cacheID;
+            generate_bitmap_cache_id(origBitmap, &cacheID);
+
+            GrResourceKey key;
+            GrTexture* result = ctx->createTexture(params, desc, cacheID, bytes, 0, &key);
+            if (NULL != result) {
+                add_genID_listener(key, origBitmap.pixelRef());
+            }
+            return result;
+
+        } while(0);
     }
 
     SkAutoLockPixels alp(*bitmap);