reactos/dll/opengl/mesa/src/mesa/swrast/s_masking.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.2
   4  *
   5  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR 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 < 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       /* treat 4xGLubyte as 1xGLuint */
  60       const GLuint srcMask = *((GLuint *) ctx->Color.ColorMask[buf]);
  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[FRAG_ATTRIB_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 }