diff options
| -rw-r--r-- | src/mesa/main/format_pack.c | 75 | ||||
| -rw-r--r-- | src/mesa/main/format_pack.h | 3 |
2 files changed, 78 insertions, 0 deletions
diff --git a/src/mesa/main/format_pack.c b/src/mesa/main/format_pack.c index 390b494c009..840559bac5e 100644 --- a/src/mesa/main/format_pack.c +++ b/src/mesa/main/format_pack.c @@ -2494,3 +2494,78 @@ _mesa_pack_uint_24_8_depth_stencil_row(gl_format format, GLuint n, return; } } + + + +/** + * Convert a boolean color mask to a packed color where each channel of + * the packed value at dst will be 0 or ~0 depending on the colorMask. + */ +void +_mesa_pack_colormask(gl_format format, const GLubyte colorMask[4], void *dst) +{ + GLfloat maskColor[4]; + + switch (_mesa_get_format_datatype(format)) { + case GL_UNSIGNED_NORMALIZED: + /* simple: 1.0 will convert to ~0 in the right bit positions */ + maskColor[0] = colorMask[0] ? 1.0 : 0.0; + maskColor[1] = colorMask[1] ? 1.0 : 0.0; + maskColor[2] = colorMask[2] ? 1.0 : 0.0; + maskColor[3] = colorMask[3] ? 1.0 : 0.0; + _mesa_pack_float_rgba_row(format, 1, + (const GLfloat (*)[4]) maskColor, dst); + break; + case GL_SIGNED_NORMALIZED: + case GL_FLOAT: + /* These formats are harder because it's hard to know the floating + * point values that will convert to ~0 for each color channel's bits. + * This solution just generates a non-zero value for each color channel + * then fixes up the non-zero values to be ~0. + * Note: we'll need to add special case code if we ever have to deal + * with formats with unequal color channel sizes, like R11_G11_B10. + * We issue a warning below for channel sizes other than 8,16,32. + */ + { + GLuint bits = _mesa_get_format_max_bits(format); /* bits per chan */ + GLuint bytes = _mesa_get_format_bytes(format); + GLuint i; + + /* this should put non-zero values into the channels of dst */ + maskColor[0] = colorMask[0] ? -1.0 : 0.0; + maskColor[1] = colorMask[1] ? -1.0 : 0.0; + maskColor[2] = colorMask[2] ? -1.0 : 0.0; + maskColor[3] = colorMask[3] ? -1.0 : 0.0; + _mesa_pack_float_rgba_row(format, 1, + (const GLfloat (*)[4]) maskColor, dst); + + /* fix-up the dst channels by converting non-zero values to ~0 */ + if (bits == 8) { + GLubyte *d = (GLubyte *) dst; + for (i = 0; i < bytes; i++) { + d[i] = d[i] ? 0xffff : 0x0; + } + } + else if (bits == 16) { + GLushort *d = (GLushort *) dst; + for (i = 0; i < bytes / 2; i++) { + d[i] = d[i] ? 0xffff : 0x0; + } + } + else if (bits == 32) { + GLuint *d = (GLuint *) dst; + for (i = 0; i < bytes / 4; i++) { + d[i] = d[i] ? 0xffffffffU : 0x0; + } + } + else { + _mesa_problem(NULL, "unexpected size in _mesa_pack_colormask()"); + return; + } + } + break; + default: + _mesa_problem(NULL, "unexpected format data type in gen_color_mask()"); + return; + } +} diff --git a/src/mesa/main/format_pack.h b/src/mesa/main/format_pack.h index 7df1356321c..f1b48051065 100644 --- a/src/mesa/main/format_pack.h +++ b/src/mesa/main/format_pack.h @@ -95,4 +95,7 @@ _mesa_pack_uint_24_8_depth_stencil_row(gl_format format, GLuint n, const GLuint *src, void *dst); +extern void +_mesa_pack_colormask(gl_format format, const GLubyte colorMask[4], void *dst); + #endif |