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 "formats.h"
  32 #include "image.h"
  33 #include "state.h"
  34
  35
  36 /**
  37  * Do error checking of the format/type parameters to glReadPixels and
  38  * glDrawPixels.
  39  * \param drawing if GL_TRUE do checking for DrawPixels, else do checking
  40  *                for ReadPixels.
  41  * \return GL_TRUE if error detected, GL_FALSE if no errors
  42  */
  43 GLboolean
  44 _mesa_error_check_format_type(struct gl_context *ctx, GLenum format, GLenum type,
  45                               GLboolean drawing)
  46 {
  47    const char *readDraw = drawing ? "Draw" : "Read";
  48    const GLboolean reading = !drawing;
  49
  50    /* state validation should have already been done */
  51    ASSERT(ctx->NewState == 0x0);
  52
  53    if (ctx->Extensions.EXT_packed_depth_stencil
  54        && type == GL_UNSIGNED_INT_24_8_EXT
  55        && format != GL_DEPTH_STENCIL_EXT) {
  56       _mesa_error(ctx, GL_INVALID_OPERATION,
  57                   "gl%sPixels(format is not GL_DEPTH_STENCIL_EXT)", readDraw);
  58       return GL_TRUE;
  59    }
  60
  61    /* basic combinations test */
  62    if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
  63       _mesa_error(ctx, GL_INVALID_ENUM,
  64                   "gl%sPixels(format or type)", readDraw);
  65       return GL_TRUE;
  66    }
  67
  68    /* additional checks */
  69    switch (format) {
  70    case GL_RG:
  71    case GL_RED:
  72    case GL_GREEN:
  73    case GL_BLUE:
  74    case GL_ALPHA:
  75    case GL_LUMINANCE:
  76    case GL_LUMINANCE_ALPHA:
  77    case GL_RGB:
  78    case GL_BGR:
  79    case GL_RGBA:
  80    case GL_BGRA:
  81    case GL_ABGR_EXT:
  82    case GL_RED_INTEGER_EXT:
  83    case GL_GREEN_INTEGER_EXT:
  84    case GL_BLUE_INTEGER_EXT:
  85    case GL_ALPHA_INTEGER_EXT:
  86    case GL_RGB_INTEGER_EXT:
  87    case GL_RGBA_INTEGER_EXT:
  88    case GL_BGR_INTEGER_EXT:
  89    case GL_BGRA_INTEGER_EXT:
  90    case GL_LUMINANCE_INTEGER_EXT:
  91    case GL_LUMINANCE_ALPHA_INTEGER_EXT:
  92       if (!drawing) {
  93          /* reading */
  94          if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
  95             _mesa_error(ctx, GL_INVALID_OPERATION,
  96                         "glReadPixels(no color buffer)");
  97             return GL_TRUE;
  98          }
  99       }
 100       break;
 101    case GL_COLOR_INDEX:
 102       if (drawing) {
 103          if (ctx->PixelMaps.ItoR.Size == 0 ||
 104              ctx->PixelMaps.ItoG.Size == 0 ||
 105              ctx->PixelMaps.ItoB.Size == 0) {
 106             _mesa_error(ctx, GL_INVALID_OPERATION,
 107                    "glDrawPixels(drawing color index pixels into RGB buffer)");
 108             return GL_TRUE;
 109          }
 110       }
 111       else {
 112          /* reading */
 113          if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
 114             _mesa_error(ctx, GL_INVALID_OPERATION,
 115                         "glReadPixels(no color buffer)");
 116             return GL_TRUE;
 117          }
 118          /* We no longer support CI-mode color buffers so trying to read
 119           * GL_COLOR_INDEX pixels is always an error.
 120           */
 121          _mesa_error(ctx, GL_INVALID_OPERATION,
 122                      "glReadPixels(color buffer is RGB)");
 123          return GL_TRUE;
 124       }
 125       break;
 126    case GL_STENCIL_INDEX:
 127       if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
 128           (reading && !_mesa_source_buffer_exists(ctx, format))) {
 129          _mesa_error(ctx, GL_INVALID_OPERATION,
 130                      "gl%sPixels(no stencil buffer)", readDraw);
 131          return GL_TRUE;
 132       }
 133       break;
 134    case GL_DEPTH_COMPONENT:
 135       if ((drawing && !_mesa_dest_buffer_exists(ctx, format))) {
 136          _mesa_error(ctx, GL_INVALID_OPERATION,
 137                      "gl%sPixels(no depth buffer)", readDraw);
 138          return GL_TRUE;
 139       }
 140       break;
 141    case GL_DEPTH_STENCIL_EXT:
 142       if (!ctx->Extensions.EXT_packed_depth_stencil ||
 143           type != GL_UNSIGNED_INT_24_8_EXT) {
 144          _mesa_error(ctx, GL_INVALID_ENUM, "gl%sPixels(type)", readDraw);
 145          return GL_TRUE;
 146       }
 147       if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
 148           (reading && !_mesa_source_buffer_exists(ctx, format))) {
 149          _mesa_error(ctx, GL_INVALID_OPERATION,
 150                      "gl%sPixels(no depth or stencil buffer)", readDraw);
 151          return GL_TRUE;
 152       }
 153       break;
 154    default:
 155       /* this should have been caught in _mesa_is_legal_format_type() */
 156       _mesa_problem(ctx, "unexpected format in _mesa_%sPixels", readDraw);
 157       return GL_TRUE;
 158    }
 159
 160    /* no errors */
 161    return GL_FALSE;
 162 }
 163
 164
 165
 166 void GLAPIENTRY
 167 _mesa_ReadPixels( GLint x, GLint y, GLsizei width, GLsizei height,
 168                   GLenum format, GLenum type, GLvoid *pixels )
 169 {
 170    GET_CURRENT_CONTEXT(ctx);
 171    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 172
 173    FLUSH_CURRENT(ctx, 0);
 174
 175    if (width < 0 || height < 0) {
 176       _mesa_error( ctx, GL_INVALID_VALUE,
 177                    "glReadPixels(width=%d height=%d)", width, height );
 178       return;
 179    }
 180
 181    if (ctx->NewState)
 182       _mesa_update_state(ctx);
 183
 184    if (_mesa_error_check_format_type(ctx, format, type, GL_FALSE)) {
 185       /* found an error */
 186       return;
 187    }
 188
 189    /* Check that the destination format and source buffer are both
 190     * integer-valued or both non-integer-valued.
 191     */
 192    if (ctx->Extensions.EXT_texture_integer && _mesa_is_color_format(format)) {
 193       const struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
 194       const GLboolean srcInteger = _mesa_is_format_integer_color(rb->Format);
 195       const GLboolean dstInteger = _mesa_is_integer_format(format);
 196       if (dstInteger != srcInteger) {
 197          _mesa_error(ctx, GL_INVALID_OPERATION,
 198                      "glReadPixels(integer / non-integer format mismatch");
 199          return;
 200       }
 201    }
 202
 203    if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 204       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
 205                   "glReadPixels(incomplete framebuffer)" );
 206       return;
 207    }
 208
 209    if (!_mesa_source_buffer_exists(ctx, format)) {
 210       _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(no readbuffer)");
 211       return;
 212    }
 213
 214    if (width == 0 || height == 0)
 215       return; /* nothing to do */
 216
 217    if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 218       if (!_mesa_validate_pbo_access(2, &ctx->Pack, width, height, 1,
 219                                      format, type, pixels)) {
 220          _mesa_error(ctx, GL_INVALID_OPERATION,
 221                      "glReadPixels(invalid PBO access)");
 222          return;
 223       }
 224
 225       if (_mesa_bufferobj_mapped(ctx->Pack.BufferObj)) {
 226          /* buffer is mapped - that's an error */
 227          _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(PBO is mapped)");
 228          return;
 229       }
 230    }
 231
 232    ctx->Driver.ReadPixels(ctx, x, y, width, height,
 233                           format, type, &ctx->Pack, pixels);
 234 }