src/mesa/main/accum.c

   1 /* $Id: accum.c,v 1.33 2000/12/26 05:09:27 keithw Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2000  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28 #ifdef PC_HEADER
  29 #include "all.h"
  30 #else
  31 #include "glheader.h"
  32 #include "accum.h"
  33 #include "context.h"
  34 #include "macros.h"
  35 #include "mem.h"
  36 #include "state.h"
  37 #include "mtypes.h"
  38 #include "swrast/swrast.h"
  39 #endif
  40
  41
  42
  43
  44 void
  45 _mesa_ClearAccum( GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha )
  46 {
  47    GLfloat tmp[4];
  48    GET_CURRENT_CONTEXT(ctx);
  49    ASSERT_OUTSIDE_BEGIN_END(ctx);
  50
  51    tmp[0] = CLAMP( red, -1.0, 1.0 );
  52    tmp[1] = CLAMP( green, -1.0, 1.0 );
  53    tmp[2] = CLAMP( blue, -1.0, 1.0 );
  54    tmp[3] = CLAMP( alpha, -1.0, 1.0 );
  55
  56    if (TEST_EQ_4V(tmp, ctx->Accum.ClearColor))
  57       return;
  58
  59    FLUSH_VERTICES(ctx, _NEW_ACCUM);
  60    COPY_4FV( ctx->Accum.ClearColor, tmp );
  61 }
  62
  63 /* Should really be a driver-supplied function?
  64  */
  65 void
  66 _mesa_Accum( GLenum op, GLfloat value )
  67 {
  68    GET_CURRENT_CONTEXT(ctx);
  69    GLuint xpos, ypos, width, height;
  70    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
  71
  72    if (ctx->Visual.AccumRedBits == 0 || ctx->DrawBuffer != ctx->ReadBuffer) {
  73       gl_error(ctx, GL_INVALID_OPERATION, "glAccum");
  74       return;
  75    }
  76
  77    if (ctx->NewState)
  78       gl_update_state( ctx );
  79
  80    /* Determine region to operate upon. */
  81    if (ctx->Scissor.Enabled) {
  82       xpos = ctx->Scissor.X;
  83       ypos = ctx->Scissor.Y;
  84       width = ctx->Scissor.Width;
  85       height = ctx->Scissor.Height;
  86    }
  87    else {
  88       /* whole window */
  89       xpos = 0;
  90       ypos = 0;
  91       width = ctx->DrawBuffer->Width;
  92       height = ctx->DrawBuffer->Height;
  93    }
  94
  95    if (!ctx->Driver.Accum ||
  96        !ctx->Driver.Accum( ctx, op, value, xpos, ypos, width, height ))
  97       _swrast_Accum( ctx, op, value, xpos, ypos, width, height );
  98 }