src/mesa/main/readpix.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.1
   4  *
   5  * Copyright (C) 1999-2008  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 #include "glheader.h"
  26 #include "imports.h"
  27 #include "bufferobj.h"
  28 #include "context.h"
  29 #include "readpix.h"
  30 #include "framebuffer.h"
  31 #include "image.h"
  32 #include "state.h"
  33
  34
  35 /**
  36  * Do error checking of the format/type parameters to glReadPixels and
  37  * glDrawPixels.
  38  * \param drawing if GL_TRUE do checking for DrawPixels, else do checking
  39  *                for ReadPixels.
  40  * \return GL_TRUE if error detected, GL_FALSE if no errors
  41  */
  42 GLboolean
  43 _mesa_error_check_format_type(GLcontext *ctx, GLenum format, GLenum type,
  44                               GLboolean drawing)
  45 {
  46    const char *readDraw = drawing ? "Draw" : "Read";
  47    const GLboolean reading = !drawing;
  48
  49    /* state validation should have already been done */
  50    ASSERT(ctx->NewState == 0x0);
  51
  52    if (ctx->Extensions.EXT_packed_depth_stencil
  53        && type == GL_UNSIGNED_INT_24_8_EXT
  54        && format != GL_DEPTH_STENCIL_EXT) {
  55       _mesa_error(ctx, GL_INVALID_OPERATION,
  56                   "gl%sPixels(format is not GL_DEPTH_STENCIL_EXT)", readDraw);
  57       return GL_TRUE;
  58    }
  59
  60    /* basic combinations test */
  61    if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
  62       _mesa_error(ctx, GL_INVALID_ENUM,
  63                   "gl%sPixels(format or type)", readDraw);
  64       return GL_TRUE;
  65    }
  66
  67    /* additional checks */
  68    switch (format) {
  69    case GL_RED:
  70    case GL_GREEN:
  71    case GL_BLUE:
  72    case GL_ALPHA:
  73    case GL_LUMINANCE:
  74    case GL_LUMINANCE_ALPHA:
  75    case GL_RGB:
  76    case GL_BGR:
  77    case GL_RGBA:
  78    case GL_BGRA:
  79    case GL_ABGR_EXT:
  80       if (!drawing) {
  81          /* reading */
  82          if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
  83             _mesa_error(ctx, GL_INVALID_OPERATION,
  84                         "glReadPixels(no color buffer)");
  85             return GL_TRUE;
  86          }
  87       }
  88       break;
  89    case GL_COLOR_INDEX:
  90       if (drawing) {
  91          if (ctx->PixelMaps.ItoR.Size == 0 ||
  92              ctx->PixelMaps.ItoG.Size == 0 ||
  93              ctx->PixelMaps.ItoB.Size == 0) {
  94             _mesa_error(ctx, GL_INVALID_OPERATION,
  95                    "glDrawPixels(drawing color index pixels into RGB buffer)");
  96             return GL_TRUE;
  97          }
  98       }
  99       else {
 100          /* reading */
 101          if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
 102             _mesa_error(ctx, GL_INVALID_OPERATION,
 103                         "glReadPixels(no color buffer)");
 104             return GL_TRUE;
 105          }
 106          /* We no longer support CI-mode color buffers so trying to read
 107           * GL_COLOR_INDEX pixels is always an error.
 108           */
 109          _mesa_error(ctx, GL_INVALID_OPERATION,
 110                      "glReadPixels(color buffer is RGB)");
 111          return GL_TRUE;
 112       }
 113       break;
 114    case GL_STENCIL_INDEX:
 115       if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
 116           (reading && !_mesa_source_buffer_exists(ctx, format))) {
 117          _mesa_error(ctx, GL_INVALID_OPERATION,
 118                      "gl%sPixels(no stencil buffer)", readDraw);
 119          return GL_TRUE;
 120       }
 121       break;
 122    case GL_DEPTH_COMPONENT:
 123       if ((drawing && !_mesa_dest_buffer_exists(ctx, format))) {
 124          _mesa_error(ctx, GL_INVALID_OPERATION,
 125                      "gl%sPixels(no depth buffer)", readDraw);
 126          return GL_TRUE;
 127       }
 128       break;
 129    case GL_DEPTH_STENCIL_EXT:
 130       if (!ctx->Extensions.EXT_packed_depth_stencil ||
 131           type != GL_UNSIGNED_INT_24_8_EXT) {
 132          _mesa_error(ctx, GL_INVALID_ENUM, "gl%sPixels(type)", readDraw);
 133          return GL_TRUE;
 134       }
 135       if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
 136           (reading && !_mesa_source_buffer_exists(ctx, format))) {
 137          _mesa_error(ctx, GL_INVALID_OPERATION,
 138                      "gl%sPixels(no depth or stencil buffer)", readDraw);
 139          return GL_TRUE;
 140       }
 141       break;
 142    default:
 143       /* this should have been caught in _mesa_is_legal_format_type() */
 144       _mesa_problem(ctx, "unexpected format in _mesa_%sPixels", readDraw);
 145       return GL_TRUE;
 146    }
 147
 148    /* no errors */
 149    return GL_FALSE;
 150 }
 151
 152
 153
 154 void GLAPIENTRY
 155 _mesa_ReadPixels( GLint x, GLint y, GLsizei width, GLsizei height,
 156                   GLenum format, GLenum type, GLvoid *pixels )
 157 {
 158    GET_CURRENT_CONTEXT(ctx);
 159    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 160
 161    FLUSH_CURRENT(ctx, 0);
 162
 163    if (width < 0 || height < 0) {
 164       _mesa_error( ctx, GL_INVALID_VALUE,
 165                    "glReadPixels(width=%d height=%d)", width, height );
 166       return;
 167    }
 168
 169    if (ctx->NewState)
 170       _mesa_update_state(ctx);
 171
 172    if (_mesa_error_check_format_type(ctx, format, type, GL_FALSE)) {
 173       /* found an error */
 174       return;
 175    }
 176
 177    if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 178       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
 179                   "glReadPixels(incomplete framebuffer)" );
 180       return;
 181    }
 182
 183    if (!_mesa_source_buffer_exists(ctx, format)) {
 184       _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(no readbuffer)");
 185       return;
 186    }
 187
 188    if (width == 0 || height == 0)
 189       return; /* nothing to do */
 190
 191    if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 192       if (!_mesa_validate_pbo_access(2, &ctx->Pack, width, height, 1,
 193                                      format, type, pixels)) {
 194          _mesa_error(ctx, GL_INVALID_OPERATION,
 195                      "glReadPixels(invalid PBO access)");
 196          return;
 197       }
 198
 199       if (_mesa_bufferobj_mapped(ctx->Pack.BufferObj)) {
 200          /* buffer is mapped - that's an error */
 201          _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(PBO is mapped)");
 202          return;
 203       }
 204    }
 205
 206    ctx->Driver.ReadPixels(ctx, x, y, width, height,
 207                           format, type, &ctx->Pack, pixels);
 208 }