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 "mtypes.h"
  34 #include "state.h"
  35
  36
  37 /**
  38  * Do error checking of the format/type parameters to glReadPixels and
  39  * glDrawPixels.
  40  * \param drawing if GL_TRUE do checking for DrawPixels, else do checking
  41  *                for ReadPixels.
  42  * \return GL_TRUE if error detected, GL_FALSE if no errors
  43  */
  44 GLboolean
  45 _mesa_error_check_format_type(struct gl_context *ctx, GLenum format, GLenum type,
  46                               GLboolean drawing)
  47 {
  48    const char *readDraw = drawing ? "Draw" : "Read";
  49    const GLboolean reading = !drawing;
  50
  51    /* state validation should have already been done */
  52    ASSERT(ctx->NewState == 0x0);
  53
  54    if (ctx->Extensions.EXT_packed_depth_stencil
  55        && type == GL_UNSIGNED_INT_24_8_EXT
  56        && format != GL_DEPTH_STENCIL_EXT) {
  57       _mesa_error(ctx, GL_INVALID_OPERATION,
  58                   "gl%sPixels(format is not GL_DEPTH_STENCIL_EXT)", readDraw);
  59       return GL_TRUE;
  60    }
  61
  62    /* basic combinations test */
  63    if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
  64       _mesa_error(ctx, GL_INVALID_ENUM,
  65                   "gl%sPixels(format or type)", readDraw);
  66       return GL_TRUE;
  67    }
  68
  69    /* additional checks */
  70    switch (format) {
  71    case GL_RG:
  72    case GL_RED:
  73    case GL_GREEN:
  74    case GL_BLUE:
  75    case GL_ALPHA:
  76    case GL_LUMINANCE:
  77    case GL_LUMINANCE_ALPHA:
  78    case GL_RGB:
  79    case GL_BGR:
  80    case GL_RGBA:
  81    case GL_BGRA:
  82    case GL_ABGR_EXT:
  83    case GL_RED_INTEGER_EXT:
  84    case GL_GREEN_INTEGER_EXT:
  85    case GL_BLUE_INTEGER_EXT:
  86    case GL_ALPHA_INTEGER_EXT:
  87    case GL_RGB_INTEGER_EXT:
  88    case GL_RGBA_INTEGER_EXT:
  89    case GL_BGR_INTEGER_EXT:
  90    case GL_BGRA_INTEGER_EXT:
  91    case GL_LUMINANCE_INTEGER_EXT:
  92    case GL_LUMINANCE_ALPHA_INTEGER_EXT:
  93       if (!drawing) {
  94          /* reading */
  95          if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
  96             _mesa_error(ctx, GL_INVALID_OPERATION,
  97                         "glReadPixels(no color buffer)");
  98             return GL_TRUE;
  99          }
 100       }
 101       break;
 102    case GL_COLOR_INDEX:
 103       if (drawing) {
 104          if (ctx->PixelMaps.ItoR.Size == 0 ||
 105              ctx->PixelMaps.ItoG.Size == 0 ||
 106              ctx->PixelMaps.ItoB.Size == 0) {
 107             _mesa_error(ctx, GL_INVALID_OPERATION,
 108                    "glDrawPixels(drawing color index pixels into RGB buffer)");
 109             return GL_TRUE;
 110          }
 111       }
 112       else {
 113          /* reading */
 114          if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
 115             _mesa_error(ctx, GL_INVALID_OPERATION,
 116                         "glReadPixels(no color buffer)");
 117             return GL_TRUE;
 118          }
 119          /* We no longer support CI-mode color buffers so trying to read
 120           * GL_COLOR_INDEX pixels is always an error.
 121           */
 122          _mesa_error(ctx, GL_INVALID_OPERATION,
 123                      "glReadPixels(color buffer is RGB)");
 124          return GL_TRUE;
 125       }
 126       break;
 127    case GL_STENCIL_INDEX:
 128       if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
 129           (reading && !_mesa_source_buffer_exists(ctx, format))) {
 130          _mesa_error(ctx, GL_INVALID_OPERATION,
 131                      "gl%sPixels(no stencil buffer)", readDraw);
 132          return GL_TRUE;
 133       }
 134       break;
 135    case GL_DEPTH_COMPONENT:
 136       if ((drawing && !_mesa_dest_buffer_exists(ctx, format))) {
 137          _mesa_error(ctx, GL_INVALID_OPERATION,
 138                      "gl%sPixels(no depth buffer)", readDraw);
 139          return GL_TRUE;
 140       }
 141       break;
 142    case GL_DEPTH_STENCIL_EXT:
 143       if (!ctx->Extensions.EXT_packed_depth_stencil ||
 144           type != GL_UNSIGNED_INT_24_8_EXT) {
 145          _mesa_error(ctx, GL_INVALID_ENUM, "gl%sPixels(type)", readDraw);
 146          return GL_TRUE;
 147       }
 148       if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
 149           (reading && !_mesa_source_buffer_exists(ctx, format))) {
 150          _mesa_error(ctx, GL_INVALID_OPERATION,
 151                      "gl%sPixels(no depth or stencil buffer)", readDraw);
 152          return GL_TRUE;
 153       }
 154       break;
 155    default:
 156       /* this should have been caught in _mesa_is_legal_format_type() */
 157       _mesa_problem(ctx, "unexpected format in _mesa_%sPixels", readDraw);
 158       return GL_TRUE;
 159    }
 160
 161    /* no errors */
 162    return GL_FALSE;
 163 }
 164
 165
 166
 167 void GLAPIENTRY
 168 _mesa_ReadPixels( GLint x, GLint y, GLsizei width, GLsizei height,
 169                   GLenum format, GLenum type, GLvoid *pixels )
 170 {
 171    GET_CURRENT_CONTEXT(ctx);
 172    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
 173
 174    FLUSH_CURRENT(ctx, 0);
 175
 176    if (width < 0 || height < 0) {
 177       _mesa_error( ctx, GL_INVALID_VALUE,
 178                    "glReadPixels(width=%d height=%d)", width, height );
 179       return;
 180    }
 181
 182    if (ctx->NewState)
 183       _mesa_update_state(ctx);
 184
 185    if (_mesa_error_check_format_type(ctx, format, type, GL_FALSE)) {
 186       /* found an error */
 187       return;
 188    }
 189
 190    /* Check that the destination format and source buffer are both
 191     * integer-valued or both non-integer-valued.
 192     */
 193    if (ctx->Extensions.EXT_texture_integer && _mesa_is_color_format(format)) {
 194       const struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
 195       const GLboolean srcInteger = _mesa_is_format_integer_color(rb->Format);
 196       const GLboolean dstInteger = _mesa_is_integer_format(format);
 197       if (dstInteger != srcInteger) {
 198          _mesa_error(ctx, GL_INVALID_OPERATION,
 199                      "glReadPixels(integer / non-integer format mismatch");
 200          return;
 201       }
 202    }
 203
 204    if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
 205       _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
 206                   "glReadPixels(incomplete framebuffer)" );
 207       return;
 208    }
 209
 210    if (!_mesa_source_buffer_exists(ctx, format)) {
 211       _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(no readbuffer)");
 212       return;
 213    }
 214
 215    if (width == 0 || height == 0)
 216       return; /* nothing to do */
 217
 218    if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
 219       if (!_mesa_validate_pbo_access(2, &ctx->Pack, width, height, 1,
 220                                      format, type, pixels)) {
 221          _mesa_error(ctx, GL_INVALID_OPERATION,
 222                      "glReadPixels(invalid PBO access)");
 223          return;
 224       }
 225
 226       if (_mesa_bufferobj_mapped(ctx->Pack.BufferObj)) {
 227          /* buffer is mapped - that's an error */
 228          _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(PBO is mapped)");
 229          return;
 230       }
 231    }
 232
 233    ctx->Driver.ReadPixels(ctx, x, y, width, height,
 234                           format, type, &ctx->Pack, pixels);
 235 }