diff options
Diffstat (limited to 'src/mesa/main/glformats.c')
| -rw-r--r-- | src/mesa/main/glformats.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/src/mesa/main/glformats.c b/src/mesa/main/glformats.c index 00478f989a6..6bd6c70af46 100644 --- a/src/mesa/main/glformats.c +++ b/src/mesa/main/glformats.c @@ -27,7 +27,204 @@ #include "context.h" #include "glformats.h" +#include "enums.h" + +enum { + ZERO = 4, + ONE = 5 +}; + +enum { + IDX_LUMINANCE = 0, + IDX_ALPHA, + IDX_INTENSITY, + IDX_LUMINANCE_ALPHA, + IDX_RGB, + IDX_RGBA, + IDX_RED, + IDX_GREEN, + IDX_BLUE, + IDX_BGR, + IDX_BGRA, + IDX_ABGR, + IDX_RG, + MAX_IDX +}; + +#define MAP1(x) MAP4(x, ZERO, ZERO, ZERO) +#define MAP2(x,y) MAP4(x, y, ZERO, ZERO) +#define MAP3(x,y,z) MAP4(x, y, z, ZERO) +#define MAP4(x,y,z,w) { x, y, z, w, ZERO, ONE } + +static const struct { + GLubyte format_idx; + GLubyte to_rgba[6]; + GLubyte from_rgba[6]; +} mappings[MAX_IDX] = +{ + { + IDX_LUMINANCE, + MAP4(0,0,0,ONE), + MAP1(0) + }, + + { + IDX_ALPHA, + MAP4(ZERO, ZERO, ZERO, 0), + MAP1(3) + }, + + { + IDX_INTENSITY, + MAP4(0, 0, 0, 0), + MAP1(0), + }, + + { + IDX_LUMINANCE_ALPHA, + MAP4(0,0,0,1), + MAP2(0,3) + }, + + { + IDX_RGB, + MAP4(0,1,2,ONE), + MAP3(0,1,2) + }, + + { + IDX_RGBA, + MAP4(0,1,2,3), + MAP4(0,1,2,3), + }, + + { + IDX_RED, + MAP4(0, ZERO, ZERO, ONE), + MAP1(0), + }, + + { + IDX_GREEN, + MAP4(ZERO, 0, ZERO, ONE), + MAP1(1), + }, + + { + IDX_BLUE, + MAP4(ZERO, ZERO, 0, ONE), + MAP1(2), + }, + + { + IDX_BGR, + MAP4(2,1,0,ONE), + MAP3(2,1,0) + }, + + { + IDX_BGRA, + MAP4(2,1,0,3), + MAP4(2,1,0,3) + }, + + { + IDX_ABGR, + MAP4(3,2,1,0), + MAP4(3,2,1,0) + }, + + { + IDX_RG, + MAP4(0, 1, ZERO, ONE), + MAP2(0, 1) + }, +}; + +/** + * Convert a GL image format enum to an IDX_* value (see above). + */ +static int +get_map_idx(GLenum value) +{ + switch (value) { + case GL_LUMINANCE: + case GL_LUMINANCE_INTEGER_EXT: + return IDX_LUMINANCE; + case GL_ALPHA: + case GL_ALPHA_INTEGER: + return IDX_ALPHA; + case GL_INTENSITY: + return IDX_INTENSITY; + case GL_LUMINANCE_ALPHA: + case GL_LUMINANCE_ALPHA_INTEGER_EXT: + return IDX_LUMINANCE_ALPHA; + case GL_RGB: + case GL_RGB_INTEGER: + return IDX_RGB; + case GL_RGBA: + case GL_RGBA_INTEGER: + return IDX_RGBA; + case GL_RED: + case GL_RED_INTEGER: + return IDX_RED; + case GL_GREEN: + return IDX_GREEN; + case GL_BLUE: + return IDX_BLUE; + case GL_BGR: + case GL_BGR_INTEGER: + return IDX_BGR; + case GL_BGRA: + case GL_BGRA_INTEGER: + return IDX_BGRA; + case GL_ABGR_EXT: + return IDX_ABGR; + case GL_RG: + case GL_RG_INTEGER: + return IDX_RG; + default: + _mesa_problem(NULL, "Unexpected inFormat %s", + _mesa_lookup_enum_by_nr(value)); + return 0; + } +} +/** + * When promoting texture formats (see below) we need to compute the + * mapping of dest components back to source components. + * This function does that. + * \param inFormat the incoming format of the texture + * \param outFormat the final texture format + * \return map[6] a full 6-component map + */ +void +_mesa_compute_component_mapping(GLenum inFormat, GLenum outFormat, GLubyte *map) +{ + const int inFmt = get_map_idx(inFormat); + const int outFmt = get_map_idx(outFormat); + const GLubyte *in2rgba = mappings[inFmt].to_rgba; + const GLubyte *rgba2out = mappings[outFmt].from_rgba; + int i; + + for (i = 0; i < 4; i++) + map[i] = in2rgba[rgba2out[i]]; + + map[ZERO] = ZERO; + map[ONE] = ONE; + +#if 0 + printf("from %x/%s to %x/%s map %d %d %d %d %d %d\n", + inFormat, _mesa_lookup_enum_by_nr(inFormat), + outFormat, _mesa_lookup_enum_by_nr(outFormat), + map[0], + map[1], + map[2], + map[3], + map[4], + map[5]); +#endif +} /** * \return GL_TRUE if type is packed pixel type, GL_FALSE otherwise. |