Add preliminary ASTC encoder
R=robertphillips@google.com Author: krajcevski@google.com Review URL: https://codereview.chromium.org/417933005
This commit is contained in:
krajcevski
Commit bot
parent
c44be0e9e4
commit
b2ef181ed6
@ -85,6 +85,8 @@
|
||||
'<(skia_src_path)/utils/SkRTConf.cpp',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor.cpp',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor.h',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor_ASTC.cpp',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor_ASTC.h',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor_R11EAC.cpp',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor_R11EAC.h',
|
||||
'<(skia_src_path)/utils/SkTextureCompressor_LATC.cpp',
|
||||
|
||||
@ -6,8 +6,9 @@
|
||||
*/
|
||||
|
||||
#include "SkTextureCompressor.h"
|
||||
#include "SkTextureCompressor_R11EAC.h"
|
||||
#include "SkTextureCompressor_ASTC.h"
|
||||
#include "SkTextureCompressor_LATC.h"
|
||||
#include "SkTextureCompressor_R11EAC.h"
|
||||
|
||||
#include "SkBitmap.h"
|
||||
#include "SkData.h"
|
||||
@ -20,29 +21,36 @@
|
||||
namespace SkTextureCompressor {
|
||||
|
||||
int GetCompressedDataSize(Format fmt, int width, int height) {
|
||||
int blockDimension = 0;
|
||||
int encodedBlockSize = 0;
|
||||
|
||||
switch (fmt) {
|
||||
// These formats are 64 bits per 4x4 block.
|
||||
case kR11_EAC_Format:
|
||||
case kLATC_Format:
|
||||
{
|
||||
static const int kBlockDimension = 4;
|
||||
static const int kEncodedBlockSize = 8;
|
||||
blockDimension = 4;
|
||||
encodedBlockSize = 8;
|
||||
break;
|
||||
|
||||
if(((width % kBlockDimension) == 0) && ((height % kBlockDimension) == 0)) {
|
||||
|
||||
const int blocksX = width / kBlockDimension;
|
||||
const int blocksY = height / kBlockDimension;
|
||||
|
||||
return blocksX * blocksY * kEncodedBlockSize;
|
||||
}
|
||||
|
||||
return -1;
|
||||
}
|
||||
// This format is 12x12 blocks to 128 bits.
|
||||
case kASTC_12x12_Format:
|
||||
blockDimension = 12;
|
||||
encodedBlockSize = 16;
|
||||
break;
|
||||
|
||||
default:
|
||||
SkFAIL("Unknown compressed format!");
|
||||
return -1;
|
||||
}
|
||||
|
||||
if(((width % blockDimension) == 0) && ((height % blockDimension) == 0)) {
|
||||
const int blocksX = width / blockDimension;
|
||||
const int blocksY = height / blockDimension;
|
||||
|
||||
return blocksX * blocksY * encodedBlockSize;
|
||||
}
|
||||
|
||||
return -1;
|
||||
}
|
||||
|
||||
bool CompressBufferToFormat(uint8_t* dst, const uint8_t* src, SkColorType srcColorType,
|
||||
@ -63,6 +71,9 @@ bool CompressBufferToFormat(uint8_t* dst, const uint8_t* src, SkColorType srcCol
|
||||
case kR11_EAC_Format:
|
||||
proc = CompressA8ToR11EAC;
|
||||
break;
|
||||
case kASTC_12x12_Format:
|
||||
proc = CompressA8To12x12ASTC;
|
||||
break;
|
||||
default:
|
||||
// Do nothing...
|
||||
break;
|
||||
|
||||
@ -18,10 +18,11 @@ namespace SkTextureCompressor {
|
||||
// Various texture compression formats that we support.
|
||||
enum Format {
|
||||
// Alpha only formats.
|
||||
kLATC_Format, // 4x4 blocks, compresses A8
|
||||
kR11_EAC_Format, // 4x4 blocks, compresses A8
|
||||
kLATC_Format, // 4x4 blocks, compresses A8
|
||||
kR11_EAC_Format, // 4x4 blocks, compresses A8
|
||||
kASTC_12x12_Format, // 12x12 blocks, compresses A8
|
||||
|
||||
kLast_Format = kR11_EAC_Format
|
||||
kLast_Format = kASTC_12x12_Format
|
||||
};
|
||||
static const int kFormatCnt = kLast_Format + 1;
|
||||
|
||||
|
||||
271
src/utils/SkTextureCompressor_ASTC.cpp
Normal file
271
src/utils/SkTextureCompressor_ASTC.cpp
Normal file
@ -0,0 +1,271 @@
|
||||
/*
|
||||
* Copyright 2014 Google Inc.
|
||||
*
|
||||
* Use of this source code is governed by a BSD-style license that can be
|
||||
* found in the LICENSE file.
|
||||
*/
|
||||
|
||||
#include "SkTextureCompressor_ASTC.h"
|
||||
|
||||
#include "SkBlitter.h"
|
||||
#include "SkEndian.h"
|
||||
|
||||
// This table contains the weight values for each texel. This is used in determining
|
||||
// how to convert a 12x12 grid of alpha values into a 6x5 grid of index values. Since
|
||||
// we have a 6x5 grid, that gives 30 values that we have to compute. For each index,
|
||||
// we store up to 20 different triplets of values. In order the triplets are:
|
||||
// weight, texel-x, texel-y
|
||||
// The weight value corresponds to the amount that this index contributes to the final
|
||||
// index value of the given texel. Hence, we need to reconstruct the 6x5 index grid
|
||||
// from their relative contribution to the 12x12 texel grid.
|
||||
//
|
||||
// The algorithm is something like this:
|
||||
// foreach index i:
|
||||
// total-weight = 0;
|
||||
// total-alpha = 0;
|
||||
// for w = 1 to 20:
|
||||
// weight = table[i][w*3];
|
||||
// texel-x = table[i][w*3 + 1];
|
||||
// texel-y = table[i][w*3 + 2];
|
||||
// if weight >= 0:
|
||||
// total-weight += weight;
|
||||
// total-alpha += weight * alphas[texel-x][texel-y];
|
||||
//
|
||||
// total-alpha /= total-weight;
|
||||
// index = top three bits of total-alpha
|
||||
//
|
||||
// If the associated index does not contribute to 20 different texels (e.g. it's in
|
||||
// a corner), then the extra texels are stored with -1's in the table.
|
||||
|
||||
static const int k6x5To12x12Table[30][60] = {
|
||||
{ 16, 0, 0, 9, 1, 0, 1, 2, 0, 10, 0, 1, 6, 1, 1, 1, 2, 1, 4, 0, 2, 2,
|
||||
1, 2, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 7, 1, 0, 15, 2, 0, 10, 3, 0, 3, 4, 0, 4, 1, 1, 9, 2, 1, 6, 3, 1, 2,
|
||||
4, 1, 2, 1, 2, 4, 2, 2, 3, 3, 2, 1, 4, 2, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 6, 3, 0, 13, 4, 0, 12, 5, 0, 4, 6, 0, 4, 3, 1, 8, 4, 1, 8, 5, 1, 3,
|
||||
6, 1, 1, 3, 2, 3, 4, 2, 3, 5, 2, 1, 6, 2, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 4, 5, 0, 12, 6, 0, 13, 7, 0, 6, 8, 0, 2, 5, 1, 7, 6, 1, 8, 7, 1, 4,
|
||||
8, 1, 1, 5, 2, 3, 6, 2, 3, 7, 2, 2, 8, 2, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 3, 7, 0, 10, 8, 0, 15, 9, 0, 7, 10, 0, 2, 7, 1, 6, 8, 1, 9, 9, 1, 4,
|
||||
10, 1, 1, 7, 2, 2, 8, 2, 4, 9, 2, 2, 10, 2, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 1, 9, 0, 9, 10, 0, 16, 11, 0, 1, 9, 1, 6, 10, 1, 10, 11, 1, 2, 10, 2, 4,
|
||||
11, 2, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 6, 0, 1, 3, 1, 1, 12, 0, 2, 7, 1, 2, 1, 2, 2, 15, 0, 3, 8, 1, 3, 1,
|
||||
2, 3, 9, 0, 4, 5, 1, 4, 1, 2, 4, 3, 0, 5, 2, 1, 5, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 3, 1, 1, 6, 2, 1, 4, 3, 1, 1, 4, 1, 5, 1, 2, 11, 2, 2, 7, 3, 2, 2,
|
||||
4, 2, 7, 1, 3, 14, 2, 3, 9, 3, 3, 3, 4, 3, 4, 1, 4, 8, 2, 4, 6, 3,
|
||||
4, 2, 4, 4, 1, 1, 5, 3, 2, 5, 2, 3, 5, 1, 4, 5}, // n = 20
|
||||
{ 2, 3, 1, 5, 4, 1, 4, 5, 1, 1, 6, 1, 5, 3, 2, 10, 4, 2, 9, 5, 2, 3,
|
||||
6, 2, 6, 3, 3, 12, 4, 3, 11, 5, 3, 4, 6, 3, 3, 3, 4, 7, 4, 4, 7, 5,
|
||||
4, 2, 6, 4, 1, 3, 5, 2, 4, 5, 2, 5, 5, 1, 6, 5}, // n = 20
|
||||
{ 2, 5, 1, 5, 6, 1, 5, 7, 1, 2, 8, 1, 3, 5, 2, 9, 6, 2, 10, 7, 2, 4,
|
||||
8, 2, 4, 5, 3, 11, 6, 3, 12, 7, 3, 6, 8, 3, 2, 5, 4, 7, 6, 4, 7, 7,
|
||||
4, 3, 8, 4, 1, 5, 5, 2, 6, 5, 2, 7, 5, 1, 8, 5}, // n = 20
|
||||
{ 1, 7, 1, 4, 8, 1, 6, 9, 1, 3, 10, 1, 2, 7, 2, 8, 8, 2, 11, 9, 2, 5,
|
||||
10, 2, 3, 7, 3, 9, 8, 3, 14, 9, 3, 7, 10, 3, 2, 7, 4, 6, 8, 4, 8, 9,
|
||||
4, 4, 10, 4, 1, 7, 5, 2, 8, 5, 3, 9, 5, 1, 10, 5}, // n = 20
|
||||
{ 3, 10, 1, 6, 11, 1, 1, 9, 2, 7, 10, 2, 12, 11, 2, 1, 9, 3, 8, 10, 3, 15,
|
||||
11, 3, 1, 9, 4, 5, 10, 4, 9, 11, 4, 2, 10, 5, 3, 11, 5, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 1, 0, 3, 1, 1, 3, 7, 0, 4, 4, 1, 4, 13, 0, 5, 7, 1, 5, 1, 2, 5, 13,
|
||||
0, 6, 7, 1, 6, 1, 2, 6, 7, 0, 7, 4, 1, 7, 1, 0, 8, 1, 1, 8, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 1, 2, 3, 1, 3, 3, 3, 1, 4, 7, 2, 4, 4, 3, 4, 1, 4, 4, 6, 1, 5, 12,
|
||||
2, 5, 8, 3, 5, 2, 4, 5, 6, 1, 6, 12, 2, 6, 8, 3, 6, 2, 4, 6, 3, 1,
|
||||
7, 7, 2, 7, 4, 3, 7, 1, 4, 7, 1, 2, 8, 1, 3, 8}, // n = 20
|
||||
{ 1, 4, 3, 1, 5, 3, 3, 3, 4, 6, 4, 4, 5, 5, 4, 2, 6, 4, 5, 3, 5, 11,
|
||||
4, 5, 10, 5, 5, 3, 6, 5, 5, 3, 6, 11, 4, 6, 10, 5, 6, 3, 6, 6, 3, 3,
|
||||
7, 6, 4, 7, 5, 5, 7, 2, 6, 7, 1, 4, 8, 1, 5, 8}, // n = 20
|
||||
{ 1, 6, 3, 1, 7, 3, 2, 5, 4, 5, 6, 4, 6, 7, 4, 3, 8, 4, 3, 5, 5, 10,
|
||||
6, 5, 11, 7, 5, 5, 8, 5, 3, 5, 6, 10, 6, 6, 11, 7, 6, 5, 8, 6, 2, 5,
|
||||
7, 5, 6, 7, 6, 7, 7, 3, 8, 7, 1, 6, 8, 1, 7, 8}, // n = 20
|
||||
{ 1, 8, 3, 1, 9, 3, 1, 7, 4, 4, 8, 4, 7, 9, 4, 3, 10, 4, 2, 7, 5, 8,
|
||||
8, 5, 12, 9, 5, 6, 10, 5, 2, 7, 6, 8, 8, 6, 12, 9, 6, 6, 10, 6, 1, 7,
|
||||
7, 4, 8, 7, 7, 9, 7, 3, 10, 7, 1, 8, 8, 1, 9, 8}, // n = 20
|
||||
{ 1, 10, 3, 1, 11, 3, 4, 10, 4, 7, 11, 4, 1, 9, 5, 7, 10, 5, 13, 11, 5, 1,
|
||||
9, 6, 7, 10, 6, 13, 11, 6, 4, 10, 7, 7, 11, 7, 1, 10, 8, 1, 11, 8, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 3, 0, 6, 2, 1, 6, 9, 0, 7, 5, 1, 7, 1, 2, 7, 15, 0, 8, 8, 1, 8, 1,
|
||||
2, 8, 12, 0, 9, 7, 1, 9, 1, 2, 9, 6, 0, 10, 3, 1, 10, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 1, 1, 6, 3, 2, 6, 2, 3, 6, 1, 4, 6, 4, 1, 7, 8, 2, 7, 6, 3, 7, 2,
|
||||
4, 7, 7, 1, 8, 14, 2, 8, 9, 3, 8, 3, 4, 8, 5, 1, 9, 11, 2, 9, 8, 3,
|
||||
9, 2, 4, 9, 3, 1, 10, 6, 2, 10, 4, 3, 10, 1, 4, 10}, // n = 20
|
||||
{ 1, 3, 6, 2, 4, 6, 2, 5, 6, 1, 6, 6, 3, 3, 7, 7, 4, 7, 7, 5, 7, 2,
|
||||
6, 7, 6, 3, 8, 12, 4, 8, 11, 5, 8, 4, 6, 8, 4, 3, 9, 10, 4, 9, 9, 5,
|
||||
9, 3, 6, 9, 2, 3, 10, 5, 4, 10, 5, 5, 10, 2, 6, 10}, // n = 20
|
||||
{ 1, 5, 6, 2, 6, 6, 2, 7, 6, 1, 8, 6, 2, 5, 7, 7, 6, 7, 7, 7, 7, 3,
|
||||
8, 7, 4, 5, 8, 11, 6, 8, 12, 7, 8, 6, 8, 8, 3, 5, 9, 9, 6, 9, 10, 7,
|
||||
9, 5, 8, 9, 1, 5, 10, 4, 6, 10, 5, 7, 10, 2, 8, 10}, // n = 20
|
||||
{ 1, 7, 6, 2, 8, 6, 3, 9, 6, 1, 10, 6, 2, 7, 7, 6, 8, 7, 8, 9, 7, 4,
|
||||
10, 7, 3, 7, 8, 9, 8, 8, 14, 9, 8, 7, 10, 8, 2, 7, 9, 7, 8, 9, 11, 9,
|
||||
9, 5, 10, 9, 1, 7, 10, 4, 8, 10, 6, 9, 10, 3, 10, 10}, // n = 20
|
||||
{ 2, 10, 6, 3, 11, 6, 1, 9, 7, 5, 10, 7, 9, 11, 7, 1, 9, 8, 8, 10, 8, 15,
|
||||
11, 8, 1, 9, 9, 7, 10, 9, 12, 11, 9, 3, 10, 10, 6, 11, 10, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 4, 0, 9, 2, 1, 9, 10, 0, 10, 6, 1, 10, 1, 2, 10, 16, 0, 11, 9, 1, 11, 1,
|
||||
2, 11, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 2, 1, 9, 4, 2, 9, 2, 3, 9, 1, 4, 9, 4, 1, 10, 9, 2, 10, 6, 3, 10, 2,
|
||||
4, 10, 7, 1, 11, 15, 2, 11, 10, 3, 11, 3, 4, 11, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 2, 3, 9, 3, 4, 9, 3, 5, 9, 1, 6, 9, 4, 3, 10, 8, 4, 10, 7, 5, 10, 2,
|
||||
6, 10, 6, 3, 11, 13, 4, 11, 12, 5, 11, 4, 6, 11, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 1, 5, 9, 3, 6, 9, 3, 7, 9, 1, 8, 9, 3, 5, 10, 8, 6, 10, 8, 7, 10, 4,
|
||||
8, 10, 4, 5, 11, 12, 6, 11, 13, 7, 11, 6, 8, 11, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 1, 7, 9, 3, 8, 9, 4, 9, 9, 2, 10, 9, 2, 7, 10, 6, 8, 10, 9, 9, 10, 4,
|
||||
10, 10, 3, 7, 11, 10, 8, 11, 15, 9, 11, 7, 10, 11, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0}, // n = 20
|
||||
{ 2, 10, 9, 4, 11, 9, 1, 9, 10, 6, 10, 10, 10, 11, 10, 1, 9, 11, 9, 10, 11, 16,
|
||||
11, 11, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0,
|
||||
0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0} // n = 20
|
||||
};
|
||||
|
||||
// Returns the alpha value of a texel at position (x, y) from src.
|
||||
// (x, y) are assumed to be in the range [0, 12).
|
||||
uint8_t get_alpha(const uint8_t *src, int rowBytes, int x, int y) {
|
||||
SkASSERT(x >= 0 && x < 12);
|
||||
SkASSERT(y >= 0 && y < 12);
|
||||
SkASSERT(rowBytes >= 12);
|
||||
return *(src + y*rowBytes + x);
|
||||
}
|
||||
|
||||
// Output the 16 bytes stored in top and bottom and advance the pointer. The bytes
|
||||
// are stored as the integers are represented in memory, so they should be swapped
|
||||
// if necessary.
|
||||
static inline void send_packing(uint8_t** dst, const uint64_t top, const uint64_t bottom) {
|
||||
uint64_t* dst64 = reinterpret_cast<uint64_t*>(*dst);
|
||||
dst64[0] = top;
|
||||
dst64[1] = bottom;
|
||||
*dst += 16;
|
||||
}
|
||||
|
||||
// Compresses an ASTC block, by looking up the proper contributions from
|
||||
// k6x5To12x12Table and computing an index from the associated values.
|
||||
static void compress_a8_astc_block(uint8_t** dst, const uint8_t* src, int rowBytes) {
|
||||
// Check for single color
|
||||
bool constant = true;
|
||||
const uint32_t firstInt = *(reinterpret_cast<const uint32_t*>(src));
|
||||
for (int i = 0; i < 12; ++i) {
|
||||
const uint32_t *rowInt = reinterpret_cast<const uint32_t *>(src + i*rowBytes);
|
||||
constant = constant && (rowInt[0] == firstInt);
|
||||
constant = constant && (rowInt[1] == firstInt);
|
||||
constant = constant && (rowInt[2] == firstInt);
|
||||
}
|
||||
|
||||
if (constant) {
|
||||
if (0 == firstInt) {
|
||||
// All of the indices are set to zero, and the colors are
|
||||
// v0 = 0, v1 = 255, so everything will be transparent.
|
||||
send_packing(dst, SkTEndian_SwapLE64(0x0000000001FE000173ULL), 0);
|
||||
return;
|
||||
} else if (0xFFFFFFFF == firstInt) {
|
||||
// All of the indices are set to zero, and the colors are
|
||||
// v0 = 255, v1 = 0, so everything will be opaque.
|
||||
send_packing(dst, SkTEndian_SwapLE64(0x000000000001FE0173ULL), 0);
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
uint8_t indices[30]; // 6x5 index grid
|
||||
for (int idx = 0; idx < 30; ++idx) {
|
||||
int weightTot = 0;
|
||||
int alphaTot = 0;
|
||||
|
||||
for (int w = 0; w < 20; ++w) {
|
||||
const int weight = k6x5To12x12Table[idx][w*3];
|
||||
if (weight > 0) {
|
||||
const int x = k6x5To12x12Table[idx][w*3 + 1];
|
||||
const int y = k6x5To12x12Table[idx][w*3 + 2];
|
||||
weightTot += weight;
|
||||
alphaTot += weight * get_alpha(src, rowBytes, x, y);
|
||||
}
|
||||
}
|
||||
|
||||
indices[idx] = (alphaTot + (weightTot/2)) / weightTot;
|
||||
}
|
||||
|
||||
// Pack indices... The ASTC block layout is fairly complicated. An extensive
|
||||
// description can be found here:
|
||||
// https://www.opengl.org/registry/specs/KHR/texture_compression_astc_hdr.txt
|
||||
//
|
||||
// Here is a summary of the options that we've chosen:
|
||||
// 1. Block mode: 0b00101110011
|
||||
// - 6x5 texel grid
|
||||
// - Single plane
|
||||
// - Low-precision index values
|
||||
// - Index range 0-7 (three bits per index)
|
||||
// 2. Partitions: 0b00
|
||||
// - One partition
|
||||
// 3. Color Endpoint Mode: 0b0000
|
||||
// - Direct luminance -- e0=(v0,v0,v0,0xFF); e1=(v1,v1,v1,0xFF);
|
||||
// 4. 8-bit endpoints:
|
||||
// v0 = 0, v1 = 255
|
||||
//
|
||||
// The rest of the block contains the 30 index values from before, which
|
||||
// are currently stored in the indices variable.
|
||||
|
||||
uint64_t top = 0x0000000001FE000173ULL;
|
||||
uint64_t bottom = 0;
|
||||
|
||||
for (int idx = 0; idx <= 20; ++idx) {
|
||||
const uint8_t index = (indices[idx] & 0xE0) >> 5;
|
||||
bottom |= static_cast<uint64_t>(index) << (61-(idx*3));
|
||||
}
|
||||
|
||||
// index 21 straddles top and bottom
|
||||
{
|
||||
const uint8_t index = (indices[21] & 0xE0) >> 5;
|
||||
bottom |= index & 1;
|
||||
top |= static_cast<uint64_t>((index >> 2) | (index & 2)) << 62;
|
||||
}
|
||||
|
||||
for (int idx = 22; idx < 30; ++idx) {
|
||||
const uint8_t index = (indices[idx] & 0xE0) >> 5;
|
||||
top |= static_cast<uint64_t>(index) << (59-(idx-22)*3);
|
||||
}
|
||||
|
||||
// Reverse each 3-bit index since indices are read in reverse order...
|
||||
uint64_t t = (bottom ^ (bottom >> 2)) & 0x2492492492492492ULL;
|
||||
bottom = bottom ^ t ^ (t << 2);
|
||||
|
||||
t = (top ^ (top >> 2)) & 0x0924924000000000ULL;
|
||||
top = top ^ t ^ (t << 2);
|
||||
|
||||
send_packing(dst, SkEndian_SwapLE64(top), SkEndian_SwapLE64(bottom));
|
||||
}
|
||||
|
||||
////////////////////////////////////////////////////////////////////////////////
|
||||
|
||||
namespace SkTextureCompressor {
|
||||
|
||||
bool CompressA8To12x12ASTC(uint8_t* dst, const uint8_t* src, int width, int height, int rowBytes) {
|
||||
if (width < 0 || ((width % 12) != 0) || height < 0 || ((height % 12) != 0)) {
|
||||
return false;
|
||||
}
|
||||
|
||||
uint8_t** dstPtr = &dst;
|
||||
for (int y = 0; y < height; y+=12) {
|
||||
for (int x = 0; x < width; x+=12) {
|
||||
compress_a8_astc_block(dstPtr, src + y*rowBytes + x, rowBytes);
|
||||
}
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
SkBlitter* CreateASTCBlitter(int width, int height, void* outputBuffer) {
|
||||
// TODO (krajcevski)
|
||||
return NULL;
|
||||
}
|
||||
|
||||
} // SkTextureCompressor
|
||||
24
src/utils/SkTextureCompressor_ASTC.h
Normal file
24
src/utils/SkTextureCompressor_ASTC.h
Normal file
@ -0,0 +1,24 @@
|
||||
/*
|
||||
* Copyright 2014 Google Inc.
|
||||
*
|
||||
* Use of this source code is governed by a BSD-style license that can be
|
||||
* found in the LICENSE file.
|
||||
*/
|
||||
|
||||
#ifndef SkTextureCompressor_ASTC_DEFINED
|
||||
#define SkTextureCompressor_ASTC_DEFINED
|
||||
|
||||
#include <stdint.h>
|
||||
|
||||
// Forward declare
|
||||
class SkBlitter;
|
||||
|
||||
namespace SkTextureCompressor {
|
||||
|
||||
bool CompressA8To12x12ASTC(uint8_t* dst, const uint8_t* src,
|
||||
int width, int height, int rowBytes);
|
||||
|
||||
SkBlitter* CreateASTCBlitter(int width, int height, void* outputBuffer);
|
||||
}
|
||||
|
||||
#endif // SkTextureCompressor_ASTC_DEFINED
|
||||
Loading…
Reference in New Issue
Block a user