Add texture compression interface and ETC1 encoder.

cc/resources/texture_compressor.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CC_RESOURCES_TEXTURE_COMPRESSOR_H_
+#define CC_RESOURCES_TEXTURE_COMPRESSOR_H_
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "cc/base/cc_export.h"
+
+namespace cc {
+
+class CC_EXPORT TextureCompressor {
+ public:
+  enum Format {
+    kFormatETC1,
+  };
+
+  enum Quality {
+    kQualityLow,
+    kQualityMedium,
+    kQualityHigh,
+  };
+
+  static scoped_ptr<TextureCompressor> Create(Format format);
+  virtual ~TextureCompressor() {}
+
+  virtual void Compress(const uint8_t* src,
+                        uint8_t* dst,
+                        int width,
+                        int height,
+                        Quality quality) = 0;
+
+ protected:
+  TextureCompressor() {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TextureCompressor);
+};
+
+}  // namespace cc
+
+#endif  // CC_RESOURCES_TEXTURE_COMPRESSOR_H_