diff options
Diffstat (limited to 'src/mesa')
| -rw-r--r-- | src/mesa/main/uniforms.c | 61 | ||||
| -rw-r--r-- | src/mesa/main/uniforms.h | 51 |
2 files changed, 57 insertions, 55 deletions
diff --git a/src/mesa/main/uniforms.c b/src/mesa/main/uniforms.c index 3170cc80a58..041e0db2203 100644 --- a/src/mesa/main/uniforms.c +++ b/src/mesa/main/uniforms.c @@ -318,55 +318,6 @@ get_uniform_rows_cols(const struct gl_program_parameter *p, } } - -/** - * GLSL uniform arrays and structs require special handling. - * - * The GL_ARB_shader_objects spec says that if you use - * glGetUniformLocation to get the location of an array, you CANNOT - * access other elements of the array by adding an offset to the - * returned location. For example, you must call - * glGetUniformLocation("foo[16]") if you want to set the 16th element - * of the array with glUniform(). - * - * HOWEVER, some other OpenGL drivers allow accessing array elements - * by adding an offset to the returned array location. And some apps - * seem to depend on that behaviour. - * - * Mesa's gl_uniform_list doesn't directly support this since each - * entry in the list describes one uniform variable, not one uniform - * element. We could insert dummy entries in the list for each array - * element after [0] but that causes complications elsewhere. - * - * We solve this problem by encoding two values in the location that's - * returned by glGetUniformLocation(): - * a) index into gl_uniform_list::Uniforms[] for the uniform - * b) an array/field offset (0 for simple types) - * - * These two values are encoded in the high and low halves of a GLint. - * By putting the uniform number in the high part and the offset in the - * low part, we can support the unofficial ability to index into arrays - * by adding offsets to the location value. - */ -static void -merge_location_offset(GLint *location, GLint offset) -{ - *location = (*location << 16) | offset; -} - - -/** - * Separate the uniform location and parameter offset. See above. - */ -static void -split_location_offset(GLint *location, GLint *offset) -{ - *offset = *location & 0xffff; - *location = *location >> 16; -} - - - /** * Called via glGetUniform[fiui]v() to get the current value of a uniform. */ @@ -382,7 +333,7 @@ _mesa_get_uniform(struct gl_context *ctx, GLuint program, GLint location, if (!shProg) return; - split_location_offset(&location, &offset); + _mesa_uniform_split_location_offset(location, &location, &offset); if (!find_uniform_parameter_pos(shProg, location, &prog, ¶mPos)) { _mesa_error(ctx, GL_INVALID_OPERATION, "glGetUniformfv(location)"); @@ -538,11 +489,11 @@ _mesa_get_uniform_location(struct gl_context *ctx, location = _mesa_lookup_uniform(shProg->Uniforms, name); } - if (location >= 0) { - merge_location_offset(&location, offset); + if (location < 0) { + return -1; } - return location; + return _mesa_uniform_merge_location_offset(location, offset); } @@ -811,7 +762,7 @@ _mesa_uniform(struct gl_context *ctx, struct gl_shader_program *shProg, return; } - split_location_offset(&location, &offset); + _mesa_uniform_split_location_offset(location, &location, &offset); if (location < 0 || location >= (GLint) shProg->Uniforms->NumUniforms) { _mesa_error(ctx, GL_INVALID_VALUE, "glUniform(location=%d)", location); @@ -992,7 +943,7 @@ _mesa_uniform_matrix(struct gl_context *ctx, struct gl_shader_program *shProg, return; } - split_location_offset(&location, &offset); + _mesa_uniform_split_location_offset(location, &location, &offset); if (location < 0 || location >= (GLint) shProg->Uniforms->NumUniforms) { _mesa_error(ctx, GL_INVALID_VALUE, "glUniformMatrix(location)"); diff --git a/src/mesa/main/uniforms.h b/src/mesa/main/uniforms.h index 5c1ddedf7a4..3630ad0eeb7 100644 --- a/src/mesa/main/uniforms.h +++ b/src/mesa/main/uniforms.h @@ -212,4 +212,55 @@ struct gl_builtin_uniform_desc { extern const struct gl_builtin_uniform_desc _mesa_builtin_uniform_desc[]; +/** + * \name GLSL uniform arrays and structs require special handling. + * + * The GL_ARB_shader_objects spec says that if you use + * glGetUniformLocation to get the location of an array, you CANNOT + * access other elements of the array by adding an offset to the + * returned location. For example, you must call + * glGetUniformLocation("foo[16]") if you want to set the 16th element + * of the array with glUniform(). + * + * HOWEVER, some other OpenGL drivers allow accessing array elements + * by adding an offset to the returned array location. And some apps + * seem to depend on that behaviour. + * + * Mesa's gl_uniform_list doesn't directly support this since each + * entry in the list describes one uniform variable, not one uniform + * element. We could insert dummy entries in the list for each array + * element after [0] but that causes complications elsewhere. + * + * We solve this problem by encoding two values in the location that's + * returned by glGetUniformLocation(): + * a) index into gl_uniform_list::Uniforms[] for the uniform + * b) an array/field offset (0 for simple types) + * + * These two values are encoded in the high and low halves of a GLint. + * By putting the uniform number in the high part and the offset in the + * low part, we can support the unofficial ability to index into arrays + * by adding offsets to the location value. + */ +/*@{*/ +/** + * Combine the uniform's base location and the offset + */ +static inline GLint +_mesa_uniform_merge_location_offset(unsigned base_location, unsigned offset) +{ + return (base_location << 16) | offset; +} + +/** + * Separate the uniform base location and parameter offset + */ +static inline void +_mesa_uniform_split_location_offset(GLint location, unsigned *base_location, + unsigned *offset) +{ + *offset = location & 0xffff; + *base_location = location >> 16; +} +/*@}*/ + #endif /* UNIFORMS_H */ |