* Supported ETC2 texture formats are:
* GL_COMPRESSED_RGB8_ETC2
* GL_COMPRESSED_SRGB8_ETC2
+ * GL_COMPRESSED_RGBA8_ETC2_EAC
*/
#include <stdbool.h>
struct etc2_block {
int distance;
- uint32_t pixel_indices;
+ uint64_t pixel_indices[2];
const int *modifier_tables[2];
bool flipped;
bool is_ind_mode;
bool is_planar_mode;
uint8_t base_colors[3][3];
uint8_t paint_colors[4][3];
+ uint8_t base_codeword;
+ uint8_t multiplier;
+ uint8_t table_index;
};
static const int etc2_distance_table[8] = {
3, 6, 11, 16, 23, 32, 41, 64 };
+static const int etc2_modifier_tables[16][8] = {
+ { -3, -6, -9, -15, 2, 5, 8, 14},
+ { -3, -7, -10, -13, 2, 6, 9, 12},
+ { -2, -5, -8, -13, 1, 4, 7, 12},
+ { -2, -4, -6, -13, 1, 3, 5, 12},
+ { -3, -6, -8, -12, 2, 5, 7, 11},
+ { -3, -7, -9, -11, 2, 6, 8, 10},
+ { -4, -7, -8, -11, 3, 6, 7, 10},
+ { -3, -5, -8, -11, 2, 4, 7, 10},
+ { -2, -6, -8, -10, 1, 5, 7, 9},
+ { -2, -5, -8, -10, 1, 4, 7, 9},
+ { -2, -4, -8, -10, 1, 3, 7, 9},
+ { -2, -5, -7, -10, 1, 4, 6, 9},
+ { -3, -4, -7, -10, 2, 3, 6, 9},
+ { -1, -2, -3, -10, 0, 1, 2, 9},
+ { -4, -6, -8, -9, 3, 5, 7, 8},
+ { -3, -5, -7, -9, 2, 4, 6, 8},
+};
+
/* define etc1_parse_block and etc. */
#define UINT8_TYPE GLubyte
#define TAG(x) x
block->flipped = (src[3] & 0x1);
}
- block->pixel_indices =
+ block->pixel_indices[0] =
(src[4] << 24) | (src[5] << 16) | (src[6] << 8) | src[7];
}
/* get pixel index */
bit = y + x * 4;
- idx = ((block->pixel_indices >> (15 + bit)) & 0x2) |
- ((block->pixel_indices >> (bit)) & 0x1);
+ idx = ((block->pixel_indices[0] >> (15 + bit)) & 0x2) |
+ ((block->pixel_indices[0] >> (bit)) & 0x1);
if (block->is_ind_mode || block->is_diff_mode) {
/* Use pixel index and subblock to get the modifier */
}
}
+static void
+etc2_alpha8_fetch_texel(const struct etc2_block *block,
+ int x, int y, uint8_t *dst)
+{
+ int modifier, alpha, bit, idx;
+ /* get pixel index */
+ bit = ((3 - y) + (3 - x) * 4) * 3;
+ idx = (block->pixel_indices[1] >> bit) & 0x7;
+ modifier = etc2_modifier_tables[block->table_index][idx];
+ alpha = block->base_codeword + modifier * block->multiplier;
+ dst[3] = etc2_clamp(alpha);
+}
+
+static void
+etc2_alpha8_parse_block(struct etc2_block *block, const uint8_t *src)
+{
+ block->base_codeword = src[0];
+ block->multiplier = (src[1] >> 4) & 0xf;
+ block->table_index = src[1] & 0xf;
+ block->pixel_indices[1] = (((uint64_t)src[2] << 40) |
+ ((uint64_t)src[3] << 32) |
+ ((uint64_t)src[4] << 24) |
+ ((uint64_t)src[5] << 16) |
+ ((uint64_t)src[6] << 8) |
+ ((uint64_t)src[7]));
+}
+
+static void
+etc2_rgba8_parse_block(struct etc2_block *block, const uint8_t *src)
+{
+ /* RGB component is parsed the same way as for MESA_FORMAT_ETC2_RGB8 */
+ etc2_rgb8_parse_block(block, src + 8);
+
+ /* Parse Alpha component */
+ etc2_alpha8_parse_block(block, src);
+}
+
+static void
+etc2_rgba8_fetch_texel(const struct etc2_block *block,
+ int x, int y, uint8_t *dst)
+{
+ etc2_rgb8_fetch_texel(block, x, y, dst);
+ etc2_alpha8_fetch_texel(block, x, y, dst);
+}
+
static void
etc2_unpack_rgb8(uint8_t *dst_row,
unsigned dst_stride,
}
}
+static void
+etc2_unpack_rgba8(uint8_t *dst_row,
+ unsigned dst_stride,
+ const uint8_t *src_row,
+ unsigned src_stride,
+ unsigned width,
+ unsigned height)
+{
+ /* If internalformat is COMPRESSED_RGBA8_ETC2_EAC, each 4 × 4 block of
+ * RGBA8888 information is compressed to 128 bits. To decode a block, the
+ * two 64-bit integers int64bitAlpha and int64bitColor are calculated.
+ */
+ const unsigned bw = 4, bh = 4, bs = 16, comps = 4;
+ struct etc2_block block;
+ unsigned x, y, i, j;
+
+ for (y = 0; y < height; y += bh) {
+ const uint8_t *src = src_row;
+
+ for (x = 0; x < width; x+= bw) {
+ etc2_rgba8_parse_block(&block, src);
+
+ for (j = 0; j < bh; j++) {
+ uint8_t *dst = dst_row + (y + j) * dst_stride + x * comps;
+ for (i = 0; i < bw; i++) {
+ etc2_rgba8_fetch_texel(&block, i, j, dst);
+ dst += comps;
+ }
+ }
+ src += bs;
+ }
+
+ src_row += src_stride;
+ }
+}
+
/* ETC2 texture formats are valid in glCompressedTexImage2D and
* glCompressedTexSubImage2D functions */
GLboolean
return GL_FALSE;
}
+GLboolean
+_mesa_texstore_etc2_rgba8_eac(TEXSTORE_PARAMS)
+{
+ ASSERT(0);
+
+ return GL_FALSE;
+}
+
void
_mesa_fetch_texel_2d_f_etc2_rgb8(const struct swrast_texture_image *texImage,
GLint i, GLint j, GLint k, GLfloat *texel)
texel[ACOMP] = 1.0f;
}
+void
+_mesa_fetch_texel_2d_f_etc2_rgba8_eac(const struct swrast_texture_image *texImage,
+ GLint i, GLint j, GLint k, GLfloat *texel)
+{
+ struct etc2_block block;
+ uint8_t dst[4];
+ const uint8_t *src;
+
+ src = texImage->Map +
+ (((texImage->RowStride + 3) / 4) * (j / 4) + (i / 4)) * 16;
+
+ etc2_rgba8_parse_block(&block, src);
+ etc2_rgba8_fetch_texel(&block, i % 4, j % 4, dst);
+
+ texel[RCOMP] = UBYTE_TO_FLOAT(dst[0]);
+ texel[GCOMP] = UBYTE_TO_FLOAT(dst[1]);
+ texel[BCOMP] = UBYTE_TO_FLOAT(dst[2]);
+ texel[ACOMP] = UBYTE_TO_FLOAT(dst[3]);
+}
+
/**
* Decode texture data in any one of following formats:
* `MESA_FORMAT_ETC2_RGB8`
* `MESA_FORMAT_ETC2_SRGB8`
+ * `MESA_FORMAT_ETC2_RGBA8_EAC`
*
* The size of the source data must be a multiple of the ETC2 block size
* even if the texture image's dimensions are not aligned to 4.
etc2_unpack_srgb8(dst_row, dst_stride,
src_row, src_stride,
src_width, src_height);
+ else if (format == MESA_FORMAT_ETC2_RGBA8_EAC)
+ etc2_unpack_rgba8(dst_row, dst_stride,
+ src_row, src_stride,
+ src_width, src_height);
}