Index: cc/resources/texture_compressor_etc1.cc |
diff --git a/cc/resources/texture_compressor_etc1.cc b/cc/resources/texture_compressor_etc1.cc |
index 61c4438c21862342f8cf0ca10b19a375364a581c..83c3f9fb034806a29bd86c669f405cae7256ddde 100644 |
--- a/cc/resources/texture_compressor_etc1.cc |
+++ b/cc/resources/texture_compressor_etc1.cc |
@@ -18,180 +18,11 @@ |
// performance hit. |
// #define USE_PERCEIVED_ERROR_METRIC |
-namespace { |
- |
-template <typename T> |
-inline T clamp(T val, T min, T max) { |
- return val < min ? min : (val > max ? max : val); |
-} |
- |
-inline uint8_t round_to_5_bits(float val) { |
- return clamp<uint8_t>(val * 31.0f / 255.0f + 0.5f, 0, 31); |
-} |
- |
-inline uint8_t round_to_4_bits(float val) { |
- return clamp<uint8_t>(val * 15.0f / 255.0f + 0.5f, 0, 15); |
-} |
- |
-union Color { |
- struct BgraColorType { |
- uint8_t b; |
- uint8_t g; |
- uint8_t r; |
- uint8_t a; |
- } channels; |
- uint8_t components[4]; |
- uint32_t bits; |
-}; |
- |
-/* |
- * Codeword tables. |
- * See: Table 3.17.2 |
- */ |
-static const int16_t g_codeword_tables[8][4] = {{-8, -2, 2, 8}, |
- {-17, -5, 5, 17}, |
- {-29, -9, 9, 29}, |
- {-42, -13, 13, 42}, |
- {-60, -18, 18, 60}, |
- {-80, -24, 24, 80}, |
- {-106, -33, 33, 106}, |
- {-183, -47, 47, 183}}; |
- |
-/* |
- * Maps modifier indices to pixel index values. |
- * See: Table 3.17.3 |
- */ |
-static const uint8_t g_mod_to_pix[4] = {3, 2, 0, 1}; |
- |
-/* |
- * The ETC1 specification index texels as follows: |
- * |
- * [a][e][i][m] [ 0][ 4][ 8][12] |
- * [b][f][j][n] <-> [ 1][ 5][ 9][13] |
- * [c][g][k][o] [ 2][ 6][10][14] |
- * [d][h][l][p] [ 3][ 7][11][15] |
- * |
- * However, when extracting sub blocks from BGRA data the natural array |
- * indexing order ends up different: |
- * |
- * vertical0: [a][e][b][f] horizontal0: [a][e][i][m] |
- * [c][g][d][h] [b][f][j][n] |
- * vertical1: [i][m][j][n] horizontal1: [c][g][k][o] |
- * [k][o][l][p] [d][h][l][p] |
- * |
- * In order to translate from the natural array indices in a sub block to the |
- * indices (number) used by specification and hardware we use this table. |
- */ |
-static const uint8_t g_idx_to_num[4][8] = { |
- {0, 4, 1, 5, 2, 6, 3, 7}, // Vertical block 0. |
- {8, 12, 9, 13, 10, 14, 11, 15}, // Vertical block 1. |
- {0, 4, 8, 12, 1, 5, 9, 13}, // Horizontal block 0. |
- {2, 6, 10, 14, 3, 7, 11, 15} // Horizontal block 1. |
-}; |
- |
-inline void WriteColors444(uint8_t* block, |
- const Color& color0, |
- const Color& color1) { |
- block[0] = (color0.channels.r & 0xf0) | (color1.channels.r >> 4); |
- block[1] = (color0.channels.g & 0xf0) | (color1.channels.g >> 4); |
- block[2] = (color0.channels.b & 0xf0) | (color1.channels.b >> 4); |
-} |
- |
-inline void WriteColors555(uint8_t* block, |
- const Color& color0, |
- const Color& color1) { |
- // Table for conversion to 3-bit two complement format. |
- static const uint8_t two_compl_trans_table[8] = { |
- 4, // -4 (100b) |
- 5, // -3 (101b) |
- 6, // -2 (110b) |
- 7, // -1 (111b) |
- 0, // 0 (000b) |
- 1, // 1 (001b) |
- 2, // 2 (010b) |
- 3, // 3 (011b) |
- }; |
- |
- int16_t delta_r = |
- static_cast<int16_t>(color1.channels.r >> 3) - (color0.channels.r >> 3); |
- int16_t delta_g = |
- static_cast<int16_t>(color1.channels.g >> 3) - (color0.channels.g >> 3); |
- int16_t delta_b = |
- static_cast<int16_t>(color1.channels.b >> 3) - (color0.channels.b >> 3); |
- DCHECK(delta_r >= -4 && delta_r <= 3); |
- DCHECK(delta_g >= -4 && delta_g <= 3); |
- DCHECK(delta_b >= -4 && delta_b <= 3); |
- |
- block[0] = (color0.channels.r & 0xf8) | two_compl_trans_table[delta_r + 4]; |
- block[1] = (color0.channels.g & 0xf8) | two_compl_trans_table[delta_g + 4]; |
- block[2] = (color0.channels.b & 0xf8) | two_compl_trans_table[delta_b + 4]; |
-} |
- |
-inline void WriteCodewordTable(uint8_t* block, |
- uint8_t sub_block_id, |
- uint8_t table) { |
- DCHECK_LT(sub_block_id, 2); |
- DCHECK_LT(table, 8); |
- |
- uint8_t shift = (2 + (3 - sub_block_id * 3)); |
- block[3] &= ~(0x07 << shift); |
- block[3] |= table << shift; |
-} |
- |
-inline void WritePixelData(uint8_t* block, uint32_t pixel_data) { |
- block[4] |= pixel_data >> 24; |
- block[5] |= (pixel_data >> 16) & 0xff; |
- block[6] |= (pixel_data >> 8) & 0xff; |
- block[7] |= pixel_data & 0xff; |
-} |
- |
-inline void WriteFlip(uint8_t* block, bool flip) { |
- block[3] &= ~0x01; |
- block[3] |= static_cast<uint8_t>(flip); |
-} |
- |
-inline void WriteDiff(uint8_t* block, bool diff) { |
- block[3] &= ~0x02; |
- block[3] |= static_cast<uint8_t>(diff) << 1; |
-} |
- |
-/** |
- * Compress and rounds BGR888 into BGR444. The resulting BGR444 color is |
- * expanded to BGR888 as it would be in hardware after decompression. The |
- * actual 444-bit data is available in the four most significant bits of each |
- * channel. |
- */ |
-inline Color MakeColor444(const float* bgr) { |
- uint8_t b4 = round_to_4_bits(bgr[0]); |
- uint8_t g4 = round_to_4_bits(bgr[1]); |
- uint8_t r4 = round_to_4_bits(bgr[2]); |
- Color bgr444; |
- bgr444.channels.b = (b4 << 4) | b4; |
- bgr444.channels.g = (g4 << 4) | g4; |
- bgr444.channels.r = (r4 << 4) | r4; |
- return bgr444; |
-} |
+namespace cc { |
-/** |
- * Compress and rounds BGR888 into BGR555. The resulting BGR555 color is |
- * expanded to BGR888 as it would be in hardware after decompression. The |
- * actual 555-bit data is available in the five most significant bits of each |
- * channel. |
- */ |
-inline Color MakeColor555(const float* bgr) { |
- uint8_t b5 = round_to_5_bits(bgr[0]); |
- uint8_t g5 = round_to_5_bits(bgr[1]); |
- uint8_t r5 = round_to_5_bits(bgr[2]); |
- Color bgr555; |
- bgr555.channels.b = (b5 << 3) | (b5 >> 2); |
- bgr555.channels.g = (g5 << 3) | (g5 >> 2); |
- bgr555.channels.r = (r5 << 3) | (r5 >> 2); |
- return bgr555; |
-} |
+namespace { |
-/** |
- * Constructs a color from a given base color and luminance value. |
- */ |
+// Constructs a color from a given base color and luminance value. |
inline Color MakeColor(const Color& base, int16_t lum) { |
int b = static_cast<int>(base.channels.b) + lum; |
int g = static_cast<int>(base.channels.g) + lum; |
@@ -203,10 +34,8 @@ inline Color MakeColor(const Color& base, int16_t lum) { |
return color; |
} |
-/** |
- * Calculates the error metric for two colors. A small error signals that the |
- * colors are similar to each other, a large error the signals the opposite. |
- */ |
+// Calculates the error metric for two colors. A small error signals that the |
+// colors are similar to each other, a large error the signals the opposite. |
inline uint32_t GetColorError(const Color& u, const Color& v) { |
#ifdef USE_PERCEIVED_ERROR_METRIC |
float delta_b = static_cast<float>(u.channels.b) - v.channels.b; |
@@ -461,15 +290,15 @@ void CompressBlock(uint8_t* dst, const Color* ver_src, const Color* hor_src) { |
} // namespace |
-namespace cc { |
- |
void TextureCompressorETC1::Compress(const uint8_t* src, |
uint8_t* dst, |
int width, |
int height, |
Quality quality) { |
- DCHECK(width >= 4 && (width & 3) == 0); |
- DCHECK(height >= 4 && (height & 3) == 0); |
+ DCHECK_GE(width, 4); |
+ DCHECK_EQ((width & 3), 0); |
+ DCHECK_GE(height, 4); |
+ DCHECK_EQ((height & 3), 0); |
Color ver_blocks[16]; |
Color hor_blocks[16]; |