Initial KTX file decoder

src/gpu/SkGr.cpp

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #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"
 
 #ifndef SK_IGNORE_ETC1_SUPPORT
+#  include "ktx.h"
 #  include "etc1.h"
 #endif
 
 /*  Fill out buffer with the compressed format Ganesh expects from a colortable
  based bitmap. [palette (colortable) + indices].
 
  At the moment Ganesh only supports 8bit version. If Ganesh allowed we others
  we could detect that the colortable.count is <= 16, and then repack the
  indices as nibbles to save RAM, but it would take more time (i.e. a lot
  slower than memcpy), so skipping that for now.
@@ skipping 99 matching lines @@
 
 static void add_genID_listener(GrResourceKey key, SkPixelRef* pixelRef) {
     SkASSERT(NULL != pixelRef);
     pixelRef->addGenIDChangeListener(SkNEW_ARGS(GrResourceInvalidator, (key)));
 }
 
 #ifndef SK_IGNORE_ETC1_SUPPORT
 static GrTexture *load_etc1_texture(GrContext* ctx,
                                     const GrTextureParams* params,
                                     const SkBitmap &bm, GrTextureDesc desc) {
-    SkData *data = bm.pixelRef()->refEncodedData();
+    SkAutoTUnref<SkData> data(bm.pixelRef()->refEncodedData());
 
     // Is this even encoded data?
     if (NULL == data) {
         return NULL;
     }
 
     // Is this a valid PKM encoded data?
     const uint8_t *bytes = data->bytes();
-    if (!etc1_pkm_is_valid(bytes)) {
+    if (etc1_pkm_is_valid(bytes)) {
+        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>(bm.width()) ||
+            encodedHeight != static_cast<uint32_t>(bm.height())) {
+            return NULL;
+        }
+
+        // Everything seems good... skip ahead to the data.
+        bytes += ETC_PKM_HEADER_SIZE;
+        desc.fConfig = kETC1_GrPixelConfig;
+    } else if (SkKTXFile::is_ktx(bytes)) {
+        SkKTXFile ktx(data);
+
+        // Is it actually an ETC1 texture?
+        if (!ktx.isETC1()) {
+            return NULL;
+        }
+
+        // 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 (ktx.width() != bm.width() || ktx.height() != bm.height()) {
+            return NULL;
+        }        
+
+        bytes = ktx.pixelData();
+        desc.fConfig = kETC1_GrPixelConfig;
+    } else {
         return NULL;
     }
 
-    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>(bm.width()) ||
-        encodedHeight != static_cast<uint32_t>(bm.height())) {
-        return NULL;
-    }
-
-    // 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(bm, &cacheID);
 
     GrResourceKey key;
     GrTexture* result = ctx->createTexture(params, desc, cacheID, bytes, 0, &key);
     if (NULL != result) {
         add_genID_listener(key, bm.pixelRef());
     }
     return result;
@@ skipping 318 matching lines @@
             copy.setShader(NULL);
             // modulate the paint alpha by the shader's solid color alpha
             U8CPU newA = SkMulDiv255Round(SkColorGetA(color), copy.getAlpha());
             copy.setColor(SkColorSetA(color, newA));
             SkPaint2GrPaintNoShader(context, copy, false, constantColor, grPaint);
         } else {
             SkPaint2GrPaintNoShader(context, skPaint, false, constantColor, grPaint);
         }
     }
 }