1 /* 2 * Mesa 3-D graphics library 3 * 4 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included 14 * in all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 22 * OTHER DEALINGS IN THE SOFTWARE. 23 */ 24 25 26 /* 27 * Implement the effect of glColorMask and glIndexMask in software. 28 */ 29 30 31 #include "main/glheader.h" 32 #include "main/macros.h" 33 34 #include "s_context.h" 35 #include "s_masking.h" 36 #include "s_span.h" 37 38 39 /** 40 * Apply the color mask to a span of rgba values. 41 */ 42 void 43 _swrast_mask_rgba_span(struct gl_context *ctx, struct gl_renderbuffer *rb, 44 SWspan *span, GLuint buf) 45 { 46 const GLuint n = span->end; 47 void *rbPixels; 48 49 assert(n < SWRAST_MAX_WIDTH); 50 assert(span->arrayMask & SPAN_RGBA); 51 52 rbPixels = _swrast_get_dest_rgba(ctx, rb, span); 53 54 /* 55 * Do component masking. 56 * Note that we're not using span->array->mask[] here. We could... 57 */ 58 if (span->array->ChanType == GL_UNSIGNED_BYTE) { 59 GLuint srcMask; 60 memcpy(&srcMask, ctx->Color.ColorMask[buf], sizeof(srcMask)); 61 const GLuint dstMask = ~srcMask; 62 const GLuint *dst = (const GLuint *) rbPixels; 63 GLuint *src = (GLuint *) span->array->rgba8; 64 GLuint i; 65 for (i = 0; i < n; i++) { 66 src[i] = (src[i] & srcMask) | (dst[i] & dstMask); 67 } 68 } 69 else if (span->array->ChanType == GL_UNSIGNED_SHORT) { 70 /* 2-byte components */ 71 /* XXX try to use 64-bit arithmetic someday */ 72 const GLushort rMask = ctx->Color.ColorMask[buf][RCOMP] ? 0xffff : 0x0; 73 const GLushort gMask = ctx->Color.ColorMask[buf][GCOMP] ? 0xffff : 0x0; 74 const GLushort bMask = ctx->Color.ColorMask[buf][BCOMP] ? 0xffff : 0x0; 75 const GLushort aMask = ctx->Color.ColorMask[buf][ACOMP] ? 0xffff : 0x0; 76 const GLushort (*dst)[4] = (const GLushort (*)[4]) rbPixels; 77 GLushort (*src)[4] = span->array->rgba16; 78 GLuint i; 79 for (i = 0; i < n; i++) { 80 src[i][RCOMP] = (src[i][RCOMP] & rMask) | (dst[i][RCOMP] & ~rMask); 81 src[i][GCOMP] = (src[i][GCOMP] & gMask) | (dst[i][GCOMP] & ~gMask); 82 src[i][BCOMP] = (src[i][BCOMP] & bMask) | (dst[i][BCOMP] & ~bMask); 83 src[i][ACOMP] = (src[i][ACOMP] & aMask) | (dst[i][ACOMP] & ~aMask); 84 } 85 } 86 else { 87 /* 4-byte components */ 88 const GLuint rMask = ctx->Color.ColorMask[buf][RCOMP] ? ~0x0 : 0x0; 89 const GLuint gMask = ctx->Color.ColorMask[buf][GCOMP] ? ~0x0 : 0x0; 90 const GLuint bMask = ctx->Color.ColorMask[buf][BCOMP] ? ~0x0 : 0x0; 91 const GLuint aMask = ctx->Color.ColorMask[buf][ACOMP] ? ~0x0 : 0x0; 92 const GLuint (*dst)[4] = (const GLuint (*)[4]) rbPixels; 93 GLuint (*src)[4] = (GLuint (*)[4]) span->array->attribs[VARYING_SLOT_COL0]; 94 GLuint i; 95 for (i = 0; i < n; i++) { 96 src[i][RCOMP] = (src[i][RCOMP] & rMask) | (dst[i][RCOMP] & ~rMask); 97 src[i][GCOMP] = (src[i][GCOMP] & gMask) | (dst[i][GCOMP] & ~gMask); 98 src[i][BCOMP] = (src[i][BCOMP] & bMask) | (dst[i][BCOMP] & ~bMask); 99 src[i][ACOMP] = (src[i][ACOMP] & aMask) | (dst[i][ACOMP] & ~aMask); 100 } 101 } 102 } 103