summaryrefslogtreecommitdiff
path: root/src/mesa/main/readpix.c
blob: 0043c8adc412a50007910eb719419bd16754b956 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/*
 * Mesa 3-D graphics library
 * Version:  7.1
 *
 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "glheader.h"
#include "imports.h"
#include "bufferobj.h"
#include "context.h"
#include "readpix.h"
#include "framebuffer.h"
#include "image.h"
#include "state.h"


/**
 * Do error checking of the format/type parameters to glReadPixels and
 * glDrawPixels.
 * \param drawing if GL_TRUE do checking for DrawPixels, else do checking
 *                for ReadPixels.
 * \return GL_TRUE if error detected, GL_FALSE if no errors
 */
GLboolean
_mesa_error_check_format_type(struct gl_context *ctx, GLenum format, GLenum type,
                              GLboolean drawing)
{
   const char *readDraw = drawing ? "Draw" : "Read";
   const GLboolean reading = !drawing;

   /* state validation should have already been done */
   ASSERT(ctx->NewState == 0x0);

   if (ctx->Extensions.EXT_packed_depth_stencil
       && type == GL_UNSIGNED_INT_24_8_EXT
       && format != GL_DEPTH_STENCIL_EXT) {
      _mesa_error(ctx, GL_INVALID_OPERATION,
                  "gl%sPixels(format is not GL_DEPTH_STENCIL_EXT)", readDraw);
      return GL_TRUE;
   }

   /* basic combinations test */
   if (!_mesa_is_legal_format_and_type(ctx, format, type)) {
      _mesa_error(ctx, GL_INVALID_ENUM,
                  "gl%sPixels(format or type)", readDraw);
      return GL_TRUE;
   }

   /* additional checks */
   switch (format) {
   case GL_RG:
   case GL_RED:
   case GL_GREEN:
   case GL_BLUE:
   case GL_ALPHA:
   case GL_LUMINANCE:
   case GL_LUMINANCE_ALPHA:
   case GL_RGB:
   case GL_BGR:
   case GL_RGBA:
   case GL_BGRA:
   case GL_ABGR_EXT:
      if (!drawing) {
         /* reading */
         if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
            _mesa_error(ctx, GL_INVALID_OPERATION,
                        "glReadPixels(no color buffer)");
            return GL_TRUE;
         }
      }
      break;
   case GL_COLOR_INDEX:
      if (drawing) {
         if (ctx->PixelMaps.ItoR.Size == 0 ||
	     ctx->PixelMaps.ItoG.Size == 0 ||
	     ctx->PixelMaps.ItoB.Size == 0) {
            _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glDrawPixels(drawing color index pixels into RGB buffer)");
            return GL_TRUE;
         }
      }
      else {
         /* reading */
         if (!_mesa_source_buffer_exists(ctx, GL_COLOR)) {
            _mesa_error(ctx, GL_INVALID_OPERATION,
                        "glReadPixels(no color buffer)");
            return GL_TRUE;
         }
         /* We no longer support CI-mode color buffers so trying to read
          * GL_COLOR_INDEX pixels is always an error.
          */
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glReadPixels(color buffer is RGB)");
         return GL_TRUE;
      }
      break;
   case GL_STENCIL_INDEX:
      if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
          (reading && !_mesa_source_buffer_exists(ctx, format))) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "gl%sPixels(no stencil buffer)", readDraw);
         return GL_TRUE;
      }
      break;
   case GL_DEPTH_COMPONENT:
      if ((drawing && !_mesa_dest_buffer_exists(ctx, format))) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "gl%sPixels(no depth buffer)", readDraw);
         return GL_TRUE;
      }
      break;
   case GL_DEPTH_STENCIL_EXT:
      if (!ctx->Extensions.EXT_packed_depth_stencil ||
          type != GL_UNSIGNED_INT_24_8_EXT) {
         _mesa_error(ctx, GL_INVALID_ENUM, "gl%sPixels(type)", readDraw);
         return GL_TRUE;
      }
      if ((drawing && !_mesa_dest_buffer_exists(ctx, format)) ||
          (reading && !_mesa_source_buffer_exists(ctx, format))) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "gl%sPixels(no depth or stencil buffer)", readDraw);
         return GL_TRUE;
      }
      break;
   default:
      /* this should have been caught in _mesa_is_legal_format_type() */
      _mesa_problem(ctx, "unexpected format in _mesa_%sPixels", readDraw);
      return GL_TRUE;
   }

   /* no errors */
   return GL_FALSE;
}
      


void GLAPIENTRY
_mesa_ReadPixels( GLint x, GLint y, GLsizei width, GLsizei height,
		  GLenum format, GLenum type, GLvoid *pixels )
{
   GET_CURRENT_CONTEXT(ctx);
   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);

   FLUSH_CURRENT(ctx, 0);

   if (width < 0 || height < 0) {
      _mesa_error( ctx, GL_INVALID_VALUE,
                   "glReadPixels(width=%d height=%d)", width, height );
      return;
   }

   if (ctx->NewState)
      _mesa_update_state(ctx);

   if (_mesa_error_check_format_type(ctx, format, type, GL_FALSE)) {
      /* found an error */
      return;
   }

   if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
      _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
                  "glReadPixels(incomplete framebuffer)" );
      return;
   }

   if (!_mesa_source_buffer_exists(ctx, format)) {
      _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(no readbuffer)");
      return;
   }

   if (width == 0 || height == 0)
      return; /* nothing to do */

   if (_mesa_is_bufferobj(ctx->Pack.BufferObj)) {
      if (!_mesa_validate_pbo_access(2, &ctx->Pack, width, height, 1,
                                     format, type, pixels)) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glReadPixels(invalid PBO access)");
         return;
      }

      if (_mesa_bufferobj_mapped(ctx->Pack.BufferObj)) {
         /* buffer is mapped - that's an error */
         _mesa_error(ctx, GL_INVALID_OPERATION, "glReadPixels(PBO is mapped)");
         return;
      }
   }

   ctx->Driver.ReadPixels(ctx, x, y, width, height,
			  format, type, &ctx->Pack, pixels);
}