readpix.c revision 3464ebd5 
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 "enums.h"
30#include "readpix.h"
31#include "framebuffer.h"
32#include "formats.h"
33#include "image.h"
34#include "mtypes.h"
35#include "pbo.h"
36#include "state.h"
37
38
39/**
40 * Do error checking of the format/type parameters to glReadPixels and
41 * glDrawPixels.
42 * \param drawing if GL_TRUE do checking for DrawPixels, else do checking
43 *                for ReadPixels.
44 * \return GL_TRUE if error detected, GL_FALSE if no errors
45 */
46GLboolean
47_mesa_error_check_format_type(struct gl_context *ctx, GLenum format,
48                              GLenum type, GLboolean drawing)
49{
50   const char *readDraw = drawing ? "Draw" : "Read";
51   const GLboolean reading = !drawing;
52
53   /* state validation should have already been done */
54   ASSERT(ctx->NewState == 0x0);
55
56   if (ctx->Extensions.EXT_packed_depth_stencil
57       && type == GL_UNSIGNED_INT_24_8_EXT
58       && format != GL_DEPTH_STENCIL_EXT) {
59      _mesa_error(ctx, GL_INVALID_OPERATION,
60                  "gl%sPixels(format is not GL_DEPTH_STENCIL_EXT)", readDraw);
61      return GL_TRUE;
62   }
63
64   /* basic combinations test */
65   if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
66      _mesa_error(ctx, GL_INVALID_ENUM,
67                  "gl%sPixels(format or type)", readDraw);
68      return GL_TRUE;
69   }
70
71   /* additional checks */
72   switch (format) {
73   case GL_RG:
74   case GL_RED:
75   case GL_GREEN:
76   case GL_BLUE:
77   case GL_ALPHA:
78   case GL_LUMINANCE:
79   case GL_LUMINANCE_ALPHA:
80   case GL_RGB:
81   case GL_BGR:
82   case GL_RGBA:
83   case GL_BGRA:
84   case GL_ABGR_EXT:
85   case GL_RED_INTEGER_EXT:
86   case GL_GREEN_INTEGER_EXT:
87   case GL_BLUE_INTEGER_EXT:
88   case GL_ALPHA_INTEGER_EXT:
89   case GL_RGB_INTEGER_EXT:
90   case GL_RGBA_INTEGER_EXT:
91   case GL_BGR_INTEGER_EXT:
92   case GL_BGRA_INTEGER_EXT:
93   case GL_LUMINANCE_INTEGER_EXT:
94   case GL_LUMINANCE_ALPHA_INTEGER_EXT:
95      if (!drawing) {
96         /* reading */
97         if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
98            _mesa_error(ctx, GL_INVALID_OPERATION,
99                        "glReadPixels(no color buffer)");
100            return GL_TRUE;
101         }
102      }
103      break;
104   case GL_COLOR_INDEX:
105      if (drawing) {
106         if (ctx->PixelMaps.ItoR.Size == 0 ||
107	     ctx->PixelMaps.ItoG.Size == 0 ||
108	     ctx->PixelMaps.ItoB.Size == 0) {
109            _mesa_error(ctx, GL_INVALID_OPERATION,
110                   "glDrawPixels(drawing color index pixels into RGB buffer)");
111            return GL_TRUE;
112         }
113      }
114      else {
115         /* reading */
116         if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
117            _mesa_error(ctx, GL_INVALID_OPERATION,
118                        "glReadPixels(no color buffer)");
119            return GL_TRUE;
120         }
121         /* We no longer support CI-mode color buffers so trying to read
122          * GL_COLOR_INDEX pixels is always an error.
123          */
124         _mesa_error(ctx, GL_INVALID_OPERATION,
125                     "glReadPixels(color buffer is RGB)");
126         return GL_TRUE;
127      }
128      break;
129   case GL_STENCIL_INDEX:
130      if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
131          (reading && !_mesa_source_buffer_exists(ctx, format))) {
132         _mesa_error(ctx, GL_INVALID_OPERATION,
133                     "gl%sPixels(no stencil buffer)", readDraw);
134         return GL_TRUE;
135      }
136      break;
137   case GL_DEPTH_COMPONENT:
138      if ((drawing && !_mesa_dest_buffer_exists(ctx, format))) {
139         _mesa_error(ctx, GL_INVALID_OPERATION,
140                     "gl%sPixels(no depth buffer)", readDraw);
141         return GL_TRUE;
142      }
143      break;
144   case GL_DEPTH_STENCIL_EXT:
145      if (!ctx->Extensions.EXT_packed_depth_stencil ||
146          type != GL_UNSIGNED_INT_24_8_EXT) {
147         _mesa_error(ctx, GL_INVALID_ENUM, "gl%sPixels(type)", readDraw);
148         return GL_TRUE;
149      }
150      if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
151          (reading && !_mesa_source_buffer_exists(ctx, format))) {
152         _mesa_error(ctx, GL_INVALID_OPERATION,
153                     "gl%sPixels(no depth or stencil buffer)", readDraw);
154         return GL_TRUE;
155      }
156      break;
157   default:
158      /* this should have been caught in _mesa_is_legal_format_type() */
159      _mesa_problem(ctx, "unexpected format in _mesa_%sPixels", readDraw);
160      return GL_TRUE;
161   }
162
163   /* no errors */
164   return GL_FALSE;
165}
166
167
168
169void GLAPIENTRY
170_mesa_ReadnPixelsARB( GLint x, GLint y, GLsizei width, GLsizei height,
171		      GLenum format, GLenum type, GLsizei bufSize,
172                      GLvoid *pixels )
173{
174   GET_CURRENT_CONTEXT(ctx);
175   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
176
177   FLUSH_CURRENT(ctx, 0);
178
179   if (MESA_VERBOSE & VERBOSE_API)
180      _mesa_debug(ctx, "glReadPixels(%d, %d, %s, %s, %p)\n",
181                  width, height,
182                  _mesa_lookup_enum_by_nr(format),
183                  _mesa_lookup_enum_by_nr(type),
184                  pixels);
185
186   if (width < 0 || height < 0) {
187      _mesa_error( ctx, GL_INVALID_VALUE,
188                   "glReadPixels(width=%d height=%d)", width, height );
189      return;
190   }
191
192   if (ctx->NewState)
193      _mesa_update_state(ctx);
194
195   if (_mesa_error_check_format_type(ctx, format, type, GL_FALSE)) {
196      /* found an error */
197      return;
198   }
199
200   /* Check that the destination format and source buffer are both
201    * integer-valued or both non-integer-valued.
202    */
203   if (ctx->Extensions.EXT_texture_integer && _mesa_is_color_format(format)) {
204      const struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
205      const GLboolean srcInteger = _mesa_is_format_integer_color(rb->Format);
206      const GLboolean dstInteger = _mesa_is_integer_format(format);
207      if (dstInteger != srcInteger) {
208         _mesa_error(ctx, GL_INVALID_OPERATION,
209                     "glReadPixels(integer / non-integer format mismatch");
210         return;
211      }
212   }
213
214   if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
215      _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
216                  "glReadPixels(incomplete framebuffer)" );
217      return;
218   }
219
220   if (!_mesa_source_buffer_exists(ctx, format)) {
221      _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(no readbuffer)");
222      return;
223   }
224
225   if (width == 0 || height == 0)
226      return; /* nothing to do */
227
228   if (!_mesa_validate_pbo_access(2, &ctx->Pack, width, height, 1,
229                                  format, type, bufSize, pixels)) {
230      if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
231         _mesa_error(ctx, GL_INVALID_OPERATION,
232                     "glReadPixels(out of bounds PBO access)");
233      } else {
234         _mesa_error(ctx, GL_INVALID_OPERATION,
235                     "glReadnPixelsARB(out of bounds access:"
236                     " bufSize (%d) is too small)", bufSize);
237      }
238      return;
239   }
240
241   if (_mesa_is_bufferobj(ctx->Pack.BufferObj) &&
242       _mesa_bufferobj_mapped(ctx->Pack.BufferObj)) {
243      /* buffer is mapped - that's an error */
244      _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(PBO is mapped)");
245      return;
246   }
247
248   ctx->Driver.ReadPixels(ctx, x, y, width, height,
249			  format, type, &ctx->Pack, pixels);
250}
251
252void GLAPIENTRY
253_mesa_ReadPixels( GLint x, GLint y, GLsizei width, GLsizei height,
254		  GLenum format, GLenum type, GLvoid *pixels )
255{
256   _mesa_ReadnPixelsARB(x, y, width, height, format, type, INT_MAX, pixels);
257}
258