#ifndef SkTextureCompressor_DEFINED
#define SkTextureCompressor_DEFINED
+#include "SkBitmapProcShader.h"
+#include "SkImageInfo.h"
+
class SkBitmap;
+class SkBlitter;
class SkData;
namespace SkTextureCompressor {
// Various texture compression formats that we support.
enum Format {
- // Alpha only format.
- kLATC_Format,
+ // Alpha only formats.
+ kLATC_Format, // 4x4 blocks, (de)compresses A8
+ kR11_EAC_Format, // 4x4 blocks, (de)compresses A8
+
+ // RGB only formats
+ kETC1_Format, // 4x4 blocks, compresses RGB 565, decompresses 8-bit RGB
+ // NOTE: ETC1 supports 8-bit RGB compression, but we
+ // currently don't have any RGB8 SkColorTypes. We could
+ // support 8-bit RGBA but we would have to preprocess the
+ // bitmap to insert alphas.
+
+ // Multi-purpose formats
+ kASTC_4x4_Format, // 4x4 blocks, no compression, decompresses RGBA
+ kASTC_5x4_Format, // 5x4 blocks, no compression, decompresses RGBA
+ kASTC_5x5_Format, // 5x5 blocks, no compression, decompresses RGBA
+ kASTC_6x5_Format, // 6x5 blocks, no compression, decompresses RGBA
+ kASTC_6x6_Format, // 6x6 blocks, no compression, decompresses RGBA
+ kASTC_8x5_Format, // 8x5 blocks, no compression, decompresses RGBA
+ kASTC_8x6_Format, // 8x6 blocks, no compression, decompresses RGBA
+ kASTC_8x8_Format, // 8x8 blocks, no compression, decompresses RGBA
+ kASTC_10x5_Format, // 10x5 blocks, no compression, decompresses RGBA
+ kASTC_10x6_Format, // 10x6 blocks, no compression, decompresses RGBA
+ kASTC_10x8_Format, // 10x8 blocks, no compression, decompresses RGBA
+ kASTC_10x10_Format, // 10x10 blocks, no compression, decompresses RGBA
+ kASTC_12x10_Format, // 12x10 blocks, no compression, decompresses RGBA
+ kASTC_12x12_Format, // 12x12 blocks, compresses A8, decompresses RGBA
- kLast_Format = kLATC_Format
+ kLast_Format = kASTC_12x12_Format
};
static const int kFormatCnt = kLast_Format + 1;
+ // Returns the size of the compressed data given the width, height, and
+ // desired compression format. If the width and height are not an appropriate
+ // multiple of the block size, then this function returns an error (-1).
+ int GetCompressedDataSize(Format fmt, int width, int height);
+
// Returns an SkData holding a blob of compressed data that corresponds
// to the bitmap. If the bitmap colorType cannot be compressed using the
// associated format, then we return NULL. The caller is responsible for
// calling unref() on the returned data.
SkData* CompressBitmapToFormat(const SkBitmap& bitmap, Format format);
+
+ // Compresses the given src data into dst. The src data is assumed to be
+ // large enough to hold width*height pixels. The dst data is expected to
+ // be large enough to hold the compressed data according to the format.
+ bool CompressBufferToFormat(uint8_t* dst, const uint8_t* src, SkColorType srcColorType,
+ int width, int height, int rowBytes, Format format,
+ bool opt = true /* Use optimization if available */);
+
+ // Decompresses the given src data from the format specified into the
+ // destination buffer. The width and height of the data passed corresponds
+ // to the width and height of the uncompressed image. The destination buffer (dst)
+ // is assumed to be large enough to hold the entire decompressed image. The
+ // decompressed image colors are determined based on the passed format.
+ //
+ // Note, CompressBufferToFormat compresses A8 data into ASTC. However,
+ // general ASTC data encodes RGBA data, so that is what the decompressor
+ // operates on.
+ //
+ // Returns true if successfully decompresses the src data.
+ bool DecompressBufferFromFormat(uint8_t* dst, int dstRowBytes, const uint8_t* src,
+ int width, int height, Format format);
+
+ // This typedef defines what the nominal aspects of a compression function
+ // are. The typedef is not meant to be used by clients of the API, but rather
+ // allows SIMD optimized compression functions to be implemented.
+ typedef bool (*CompressionProc)(uint8_t* dst, const uint8_t* src,
+ int width, int height, int rowBytes);
+
+ // Returns true if there exists a blitter for the specified format.
+ inline bool ExistsBlitterForFormat(Format format) {
+ switch (format) {
+ case kLATC_Format:
+ case kR11_EAC_Format:
+ case kASTC_12x12_Format:
+ return true;
+
+ default:
+ return false;
+ }
+ }
+
+ // Returns the blitter for the given compression format. Note, the blitter
+ // is intended to be used with the proper input. I.e. if you try to blit
+ // RGB source data into an R11 EAC texture, you're gonna have a bad time.
+ SkBlitter* CreateBlitterForFormat(int width, int height, void* compressedBuffer,
+ SkTBlitterAllocator *allocator, Format format);
+
+ // Returns the desired dimensions of the block size for the given format. These dimensions
+ // don't necessarily correspond to the specification's dimensions, since there may
+ // be specialized algorithms that operate on multiple blocks at once. If the
+ // flag 'matchSpec' is true, then the actual dimensions from the specification are
+ // returned. If the flag is false, then these dimensions reflect the appropriate operable
+ // dimensions of the compression functions.
+ void GetBlockDimensions(Format format, int* dimX, int* dimY, bool matchSpec = false);
}
#endif
projects / platform / framework / web / crosswalk.git / blobdiff