src/mesa/main/accum.c

   1 /* $Id: accum.c,v 1.31 2000/10/31 18:09:44 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 "types.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    GET_CURRENT_CONTEXT(ctx);
  48    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glAccum");
  49
  50    ctx->Accum.ClearColor[0] = CLAMP( red, -1.0, 1.0 );
  51    ctx->Accum.ClearColor[1] = CLAMP( green, -1.0, 1.0 );
  52    ctx->Accum.ClearColor[2] = CLAMP( blue, -1.0, 1.0 );
  53    ctx->Accum.ClearColor[3] = CLAMP( alpha, -1.0, 1.0 );
  54    ctx->NewState |= _NEW_ACCUM;
  55 }
  56
  57
  58 void
  59 _mesa_Accum( GLenum op, GLfloat value )
  60 {
  61    GET_CURRENT_CONTEXT(ctx);
  62    GLuint xpos, ypos, width, height;
  63
  64    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glAccum");
  65
  66    if (ctx->Visual.AccumRedBits == 0 || ctx->DrawBuffer != ctx->ReadBuffer) {
  67       gl_error(ctx, GL_INVALID_OPERATION, "glAccum");
  68       return;
  69    }
  70
  71    if (ctx->NewState)
  72       gl_update_state( ctx );
  73
  74    /* Determine region to operate upon. */
  75    if (ctx->Scissor.Enabled) {
  76       xpos = ctx->Scissor.X;
  77       ypos = ctx->Scissor.Y;
  78       width = ctx->Scissor.Width;
  79       height = ctx->Scissor.Height;
  80    }
  81    else {
  82       /* whole window */
  83       xpos = 0;
  84       ypos = 0;
  85       width = ctx->DrawBuffer->Width;
  86       height = ctx->DrawBuffer->Height;
  87    }
  88
  89    if (!ctx->Driver.Accum ||
  90        !ctx->Driver.Accum( ctx, op, value, xpos, ypos, width, height ))
  91       _swrast_Accum( ctx, op, value, xpos, ypos, width, height );
  92 }