src/mesa/main/accum.c

   1
   2 /*
   3  * Mesa 3-D graphics library
   4  * Version:  4.1
   5  *
   6  * Copyright (C) 1999-2002  Brian Paul   All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 #include "glheader.h"
  27 #include "accum.h"
  28 #include "context.h"
  29 #include "imports.h"
  30 #include "macros.h"
  31 #include "state.h"
  32 #include "mtypes.h"
  33
  34
  35 void GLAPIENTRY
  36 _mesa_ClearAccum( GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha )
  37 {
  38    GLfloat tmp[4];
  39    GET_CURRENT_CONTEXT(ctx);
  40    ASSERT_OUTSIDE_BEGIN_END(ctx);
  41
  42    tmp[0] = CLAMP( red,   -1.0F, 1.0F );
  43    tmp[1] = CLAMP( green, -1.0F, 1.0F );
  44    tmp[2] = CLAMP( blue,  -1.0F, 1.0F );
  45    tmp[3] = CLAMP( alpha, -1.0F, 1.0F );
  46
  47    if (TEST_EQ_4V(tmp, ctx->Accum.ClearColor))
  48       return;
  49
  50    FLUSH_VERTICES(ctx, _NEW_ACCUM);
  51    COPY_4FV( ctx->Accum.ClearColor, tmp );
  52 }
  53
  54 /* Should really be a driver-supplied function?
  55  */
  56 void GLAPIENTRY
  57 _mesa_Accum( GLenum op, GLfloat value )
  58 {
  59    GET_CURRENT_CONTEXT(ctx);
  60    GLuint xpos, ypos, width, height;
  61    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
  62
  63    if (ctx->Visual.accumRedBits == 0 || ctx->DrawBuffer != ctx->ReadBuffer) {
  64       _mesa_error(ctx, GL_INVALID_OPERATION, "glAccum");
  65       return;
  66    }
  67
  68    if (ctx->NewState)
  69       _mesa_update_state( ctx );
  70
  71    /* Determine region to operate upon. */
  72    if (ctx->Scissor.Enabled) {
  73       xpos = ctx->Scissor.X;
  74       ypos = ctx->Scissor.Y;
  75       width = ctx->Scissor.Width;
  76       height = ctx->Scissor.Height;
  77    }
  78    else {
  79       /* whole window */
  80       xpos = 0;
  81       ypos = 0;
  82       width = ctx->DrawBuffer->Width;
  83       height = ctx->DrawBuffer->Height;
  84    }
  85
  86    ctx->Driver.Accum( ctx, op, value, xpos, ypos, width, height );
  87 }
  88
  89 void
  90 _mesa_init_accum( GLcontext *ctx )
  91 {
  92    /* Accumulate buffer group */
  93    ASSIGN_4V( ctx->Accum.ClearColor, 0.0, 0.0, 0.0, 0.0 );
  94 }