From 8ec721264c7ae0f73a520362963b2691bf098b9b Mon Sep 17 00:00:00 2001 From: Chad Versace Date: Tue, 10 Jul 2012 16:34:27 -0700 Subject: [PATCH] mesa: Add function for decoding ETC1 textures Add function _mesa_etc1_unpack_rgba8888. It is intended to be used by glCompressedTexSubImage2D to decode ETC1 textures into RGBA. CC: Chia-I Reviewed-by: Kenneth Graunke Signed-off-by: Chad Versace --- src/mesa/main/texcompress_etc.c | 32 ++++++++++++++++++++++++++++++++ src/mesa/main/texcompress_etc.h | 8 ++++++++ 2 files changed, 40 insertions(+) diff --git a/src/mesa/main/texcompress_etc.c b/src/mesa/main/texcompress_etc.c index 5b331a92a14..c645f52b9e1 100644 --- a/src/mesa/main/texcompress_etc.c +++ b/src/mesa/main/texcompress_etc.c @@ -69,3 +69,35 @@ _mesa_fetch_texel_2d_f_etc1_rgb8(const struct swrast_texture_image *texImage, texel[BCOMP] = UBYTE_TO_FLOAT(dst[2]); texel[ACOMP] = 1.0f; } + +/** + * Decode texture data in format `MESA_FORMAT_ETC1_RGB8` to + * `MESA_FORMAT_ABGR8888`. + * + * The size of the source data must be a multiple of the ETC1 block size, + * which is 8, even if the texture image's dimensions are not aligned to 4. + * From the GL_OES_compressed_ETC1_RGB8_texture spec: + * The texture is described as a number of 4x4 pixel blocks. If the + * texture (or a particular mip-level) is smaller than 4 pixels in + * any dimension (such as a 2x2 or a 8x1 texture), the texture is + * found in the upper left part of the block(s), and the rest of the + * pixels are not used. For instance, a texture of size 4x2 will be + * placed in the upper half of a 4x4 block, and the lower half of the + * pixels in the block will not be accessed. + * + * \param src_width in pixels + * \param src_height in pixels + * \param dst_stride in bytes + */ +void +_mesa_etc1_unpack_rgba8888(uint8_t *dst_row, + unsigned dst_stride, + const uint8_t *src_row, + unsigned src_stride, + unsigned src_width, + unsigned src_height) +{ + etc1_unpack_rgba8888(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 8e8427f8fd4..bfba4ff85e9 100644 --- a/src/mesa/main/texcompress_etc.h +++ b/src/mesa/main/texcompress_etc.h @@ -37,4 +37,12 @@ void _mesa_fetch_texel_2d_f_etc1_rgb8(const struct swrast_texture_image *texImage, GLint i, GLint j, GLint k, GLfloat *texel); +void +_mesa_etc1_unpack_rgba8888(uint8_t *dst_row, + unsigned dst_stride, + const uint8_t *src_row, + unsigned src_stride, + unsigned src_width, + unsigned src_height); + #endif -- 2.30.2