Add support for all compressed formats in KTX file format

R=robertphillips@google.com

Author: krajcevski@google.com

Review URL: https://codereview.chromium.org/440783004

2 files changed, 33 insertions, 3 deletions

diff --git a/third_party/ktx/ktx.cpp b/third_party/ktx/ktx.cpp
index a05498b7e..ebcc5eb18 100644
--- a/third_party/ktx/ktx.cpp
+++ b/third_party/ktx/ktx.cpp
@@ -12,9 +12,27 @@
 #include "SkEndian.h"
 
 #include "gl/GrGLDefines.h"
+#include "GrConfig.h"
 
 #include "etc1.h"
 
+static inline uint32_t compressed_fmt_to_gl_define(SkTextureCompressor::Format fmt) {
+    static const uint32_t kGLDefineMap[SkTextureCompressor::kFormatCnt] = {
+        GR_GL_COMPRESSED_LUMINANCE_LATC1,  // kLATC_Format
+        GR_GL_COMPRESSED_R11,  // kR11_EAC_Format
+        GR_GL_COMPRESSED_RGB8_ETC1,  // kETC1_Format
+        GR_GL_COMPRESSED_RGBA_ASTC_12x12,  // kASTC_12x12_Format
+    };
+
+    GR_STATIC_ASSERT(0 == SkTextureCompressor::kLATC_Format);
+    GR_STATIC_ASSERT(1 == SkTextureCompressor::kR11_EAC_Format);
+    GR_STATIC_ASSERT(2 == SkTextureCompressor::kETC1_Format);
+    GR_STATIC_ASSERT(3 == SkTextureCompressor::kASTC_12x12_Format);
+    GR_STATIC_ASSERT(SK_ARRAY_COUNT(kGLDefineMap) == SkTextureCompressor::kFormatCnt);
+
+    return kGLDefineMap[fmt];
+}
+
 #define KTX_FILE_IDENTIFIER_SIZE 12
 static const uint8_t KTX_FILE_IDENTIFIER[KTX_FILE_IDENTIFIER_SIZE] = {
     0xAB, 0x4B, 0x54, 0x58, 0x20, 0x31, 0x31, 0xBB, 0x0D, 0x0A, 0x1A, 0x0A
@@ -123,8 +141,19 @@ SkString SkKTXFile::getValueForKey(const SkString& key) const {
     return SkString();
 }
 
-bool SkKTXFile::isETC1() const {
-    return this->valid() && GR_GL_COMPRESSED_RGB8_ETC1 == fHeader.fGLInternalFormat;
+bool SkKTXFile::isCompressedFormat(SkTextureCompressor::Format fmt) const {
+    if (!this->valid()) {
+        return false;
+    }
+
+    // This has many aliases
+    bool isFmt = false;
+    if (fmt == SkTextureCompressor::kLATC_Format) {
+        isFmt = GR_GL_COMPRESSED_RED_RGTC1 == fHeader.fGLInternalFormat ||
+                GR_GL_COMPRESSED_3DC_X == fHeader.fGLInternalFormat;
+    }
+
+    return isFmt || compressed_fmt_to_gl_define(fmt) == fHeader.fGLInternalFormat;
 }
 
 bool SkKTXFile::isRGBA8() const {
diff --git a/third_party/ktx/ktx.h b/third_party/ktx/ktx.h
index 2f445a817..1114b49bf 100644
--- a/third_party/ktx/ktx.h
+++ b/third_party/ktx/ktx.h
@@ -11,6 +11,7 @@
 #define SkKTXFile_DEFINED
 
 #include "SkData.h"
+#include "SkTextureCompressor.h"
 #include "SkTypes.h"
 #include "SkTDArray.h"
 #include "SkString.h"
@@ -58,7 +59,7 @@ public:
 
     int numMipmaps() const { return static_cast<int>(fHeader.fNumberOfMipmapLevels); }
 
-    bool isETC1() const;
+    bool isCompressedFormat(SkTextureCompressor::Format fmt) const;
     bool isRGBA8() const;
     bool isRGB8() const;