[Mesa-dev] [PATCH 07/13] mesa: Add decoding functions for GL_COMPRESSED_R11_EAC
Anuj Phogat
anuj.phogat at gmail.com
Mon Nov 12 19:48:51 PST 2012
Data in GL_COMPRESSED_R11_EAC format is decoded and stored in
MESA_FORMAT_R16.
Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
---
src/mesa/main/texcompress_etc.c | 122 ++++++++++++++++++++++++++++++++++++++-
src/mesa/main/texcompress_etc.h | 6 ++
2 files changed, 125 insertions(+), 3 deletions(-)
diff --git a/src/mesa/main/texcompress_etc.c b/src/mesa/main/texcompress_etc.c
index 8cb40a8..889ac48 100644
--- a/src/mesa/main/texcompress_etc.c
+++ b/src/mesa/main/texcompress_etc.c
@@ -29,6 +29,7 @@
* GL_COMPRESSED_SRGB8_ETC2
* GL_COMPRESSED_RGBA8_ETC2_EAC
* GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC
+ * GL_COMPRESSED_R11_EAC
*/
#include <stdbool.h>
@@ -304,6 +305,14 @@ etc2_base_color_v_planar(const uint8_t *in, GLuint index)
}
}
+static GLint
+etc2_get_pixel_index(const struct etc2_block *block, int x, int y)
+{
+ int bit = ((3 - y) + (3 - x) * 4) * 3;
+ int idx = (block->pixel_indices[1] >> bit) & 0x7;
+ return idx;
+}
+
static uint8_t
etc2_clamp(int color)
{
@@ -311,6 +320,13 @@ etc2_clamp(int color)
return (uint8_t) CLAMP(color, 0, 255);
}
+static GLushort
+etc2_clamp2(int color)
+{
+ /* CLAMP(color, 0, 2047) */
+ return (GLushort) CLAMP(color, 0, 2047);
+}
+
static void
etc2_rgb8_parse_block(struct etc2_block *block, const uint8_t *src)
{
@@ -486,16 +502,41 @@ static void
etc2_alpha8_fetch_texel(const struct etc2_block *block,
int x, int y, uint8_t *dst)
{
- int modifier, alpha, bit, idx;
+ int modifier, alpha, idx;
/* get pixel index */
- bit = ((3 - y) + (3 - x) * 4) * 3;
- idx = (block->pixel_indices[1] >> bit) & 0x7;
+ idx = etc2_get_pixel_index(block, x, y);
modifier = etc2_modifier_tables[block->table_index][idx];
alpha = block->base_codeword + modifier * block->multiplier;
dst[3] = etc2_clamp(alpha);
}
static void
+etc2_r11_fetch_texel(const struct etc2_block *block,
+ int x, int y, uint8_t *dst)
+{
+ GLint modifier, idx;
+ GLshort color;
+ /* Get pixel index */
+ idx = etc2_get_pixel_index(block, x, y);
+ modifier = etc2_modifier_tables[block->table_index][idx];
+
+ if (block->multiplier != 0)
+ /* clamp2(base codeword × 8 + 4 + modifier × multiplier × 8) */
+ color = etc2_clamp2(((block->base_codeword << 3) | 0x4) +
+ ((modifier * block->multiplier) << 3));
+ else
+ color = etc2_clamp2(((block->base_codeword << 3) | 0x4) + modifier);
+
+ /* Extend 11 bits color value to 16 bits. OpenGL ES 3.0 specification
+ * allows extending the color value to any number of bits. But, an
+ * implementation is not allowed to truncate the 11-bit value to less than
+ * 11 bits."
+ */
+ color = (color << 5) | (color >> 6);
+ ((GLushort *)dst)[0] = color;
+}
+
+static void
etc2_alpha8_parse_block(struct etc2_block *block, const uint8_t *src)
{
block->base_codeword = src[0];
@@ -510,6 +551,13 @@ etc2_alpha8_parse_block(struct etc2_block *block, const uint8_t *src)
}
static void
+etc2_r11_parse_block(struct etc2_block *block, const uint8_t *src)
+{
+ /* Parsing logic remains same as for etc2_alpha8_parse_block */
+ etc2_alpha8_parse_block(block, src);
+}
+
+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 */
@@ -681,6 +729,41 @@ etc2_unpack_srgb8_alpha8(uint8_t *dst_row,
}
}
+static void
+etc2_unpack_r11(uint8_t *dst_row,
+ unsigned dst_stride,
+ const uint8_t *src_row,
+ unsigned src_stride,
+ unsigned width,
+ unsigned height)
+{
+ /* If internalformat is COMPRESSED_R11_EAC, each 4 × 4 block of
+ color information is compressed to 64 bits.
+ */
+ const unsigned bw = 4, bh = 4, bs = 8, comps = 1, comp_size = 2;
+ 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_r11_parse_block(&block, src);
+
+ for (j = 0; j < bh; j++) {
+ uint8_t *dst = dst_row + (y + j) * dst_stride + x * comps * comp_size;
+ for (i = 0; i < bw; i++) {
+ etc2_r11_fetch_texel(&block, i, j, dst);
+ dst += comps * comp_size;
+ }
+ }
+ src += bs;
+ }
+
+ src_row += src_stride;
+ }
+}
+
/* ETC2 texture formats are valid in glCompressedTexImage2D and
* glCompressedTexSubImage2D functions */
GLboolean
@@ -715,6 +798,14 @@ _mesa_texstore_etc2_srgb8_alpha8_eac(TEXSTORE_PARAMS)
return GL_FALSE;
}
+GLboolean
+_mesa_texstore_etc2_r11_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)
@@ -797,12 +888,33 @@ _mesa_fetch_texel_2d_f_etc2_srgb8_alpha8_eac(const struct
texel[ACOMP] = UBYTE_TO_FLOAT(dst[3]);
}
+void
+_mesa_fetch_texel_2d_f_etc2_r11_eac(const struct swrast_texture_image *texImage,
+ GLint i, GLint j, GLint k, GLfloat *texel)
+{
+ struct etc2_block block;
+ GLushort dst;
+ const uint8_t *src;
+
+ src = texImage->Map +
+ (((texImage->RowStride + 3) / 4) * (j / 4) + (i / 4)) * 8;
+
+ etc2_r11_parse_block(&block, src);
+ etc2_r11_fetch_texel(&block, i % 4, j % 4, (uint8_t *)&dst);
+
+ texel[RCOMP] = USHORT_TO_FLOAT(dst);
+ texel[GCOMP] = 0.0f;
+ texel[BCOMP] = 0.0f;
+ texel[ACOMP] = 1.0f;
+}
+
/**
* Decode texture data in any one of following formats:
* `MESA_FORMAT_ETC2_RGB8`
* `MESA_FORMAT_ETC2_SRGB8`
* `MESA_FORMAT_ETC2_RGBA8_EAC`
* `MESA_FORMAT_ETC2_SRGB8_ALPHA8_EAC`
+ * `MESA_FORMAT_ETC2_R11_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.
@@ -837,4 +949,8 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
etc2_unpack_srgb8_alpha8(dst_row, dst_stride,
src_row, src_stride,
src_width, src_height);
+ else if (format == MESA_FORMAT_ETC2_R11_EAC)
+ etc2_unpack_r11(dst_row, dst_stride,
+ src_row, src_stride,
+ src_width, src_height);
}
diff --git a/src/mesa/main/texcompress_etc.h b/src/mesa/main/texcompress_etc.h
index cfe8da3..85c474c 100644
--- a/src/mesa/main/texcompress_etc.h
+++ b/src/mesa/main/texcompress_etc.h
@@ -46,6 +46,9 @@ _mesa_texstore_etc2_rgba8_eac(TEXSTORE_PARAMS);
GLboolean
_mesa_texstore_etc2_srgb8_alpha8_eac(TEXSTORE_PARAMS);
+GLboolean
+_mesa_texstore_etc2_r11_eac(TEXSTORE_PARAMS);
+
void
_mesa_fetch_texel_2d_f_etc1_rgb8(const struct swrast_texture_image *texImage,
GLint i, GLint j, GLint k, GLfloat *texel);
@@ -64,6 +67,9 @@ _mesa_fetch_texel_2d_f_etc2_srgb8_alpha8_eac(const struct
swrast_texture_image *texImage,
GLint i, GLint j,
GLint k, GLfloat *texel);
+void
+_mesa_fetch_texel_2d_f_etc2_r11_eac(const struct swrast_texture_image *texImage,
+ GLint i, GLint j, GLint k, GLfloat *texel);
void
_mesa_etc1_unpack_rgba8888(uint8_t *dst_row,
--
1.7.7.6
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