api_validate.c revision 434ec3ada841915a00ffc23f699401eb3e7b37ee 
1/*
2 * Mesa 3-D graphics library
3 * Version:  7.1
4 *
5 * Copyright (C) 1999-2007  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 "api_validate.h"
27#include "bufferobj.h"
28#include "context.h"
29#include "imports.h"
30#include "mtypes.h"
31#include "state.h"
32
33
34
35/**
36 * \return  number of bytes in array [count] of type.
37 */
38static GLsizei
39index_bytes(GLenum type, GLsizei count)
40{
41   if (type == GL_UNSIGNED_INT) {
42      return count * sizeof(GLuint);
43   }
44   else if (type == GL_UNSIGNED_BYTE) {
45      return count * sizeof(GLubyte);
46   }
47   else {
48      ASSERT(type == GL_UNSIGNED_SHORT);
49      return count * sizeof(GLushort);
50   }
51}
52
53
54/**
55 * Find the max index in the given element/index buffer
56 */
57static GLuint
58max_buffer_index(GLcontext *ctx, GLuint count, GLenum type,
59                 const void *indices,
60                 struct gl_buffer_object *elementBuf)
61{
62   const GLubyte *map = NULL;
63   GLuint max = 0;
64   GLuint i;
65
66   if (_mesa_is_bufferobj(elementBuf)) {
67      /* elements are in a user-defined buffer object.  need to map it */
68      map = ctx->Driver.MapBuffer(ctx, GL_ELEMENT_ARRAY_BUFFER,
69                                  GL_READ_ONLY, elementBuf);
70      /* Actual address is the sum of pointers */
71      indices = (const GLvoid *) ADD_POINTERS(map, (const GLubyte *) indices);
72   }
73
74   if (type == GL_UNSIGNED_INT) {
75      for (i = 0; i < count; i++)
76         if (((GLuint *) indices)[i] > max)
77            max = ((GLuint *) indices)[i];
78   }
79   else if (type == GL_UNSIGNED_SHORT) {
80      for (i = 0; i < count; i++)
81         if (((GLushort *) indices)[i] > max)
82            max = ((GLushort *) indices)[i];
83   }
84   else {
85      ASSERT(type == GL_UNSIGNED_BYTE);
86      for (i = 0; i < count; i++)
87         if (((GLubyte *) indices)[i] > max)
88            max = ((GLubyte *) indices)[i];
89   }
90
91   if (map) {
92      ctx->Driver.UnmapBuffer(ctx, GL_ELEMENT_ARRAY_BUFFER_ARB, elementBuf);
93   }
94
95   return max;
96}
97
98
99/**
100 * Check if OK to render by examining framebuffer status and vertex arrays.
101 */
102static GLboolean
103check_valid_to_render(GLcontext *ctx, char *function)
104{
105   if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
106      _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
107                  "glDraw%s(incomplete framebuffer)", function);
108      return GL_FALSE;
109   }
110
111#if FEATURE_es2_glsl
112   /* For ES2, we can draw if any vertex array is enabled (and we should
113    * always have a vertex program/shader).
114    */
115   if (ctx->Array.ArrayObj->_Enabled == 0x0 || !ctx->VertexProgram._Current)
116      return GL_FALSE;
117#else
118   /* For regular OpenGL, only draw if we have vertex positions (regardless
119    * of whether or not we have a vertex program/shader).
120    */
121   if (!ctx->Array.ArrayObj->Vertex.Enabled &&
122       !ctx->Array.ArrayObj->VertexAttrib[0].Enabled)
123      return GL_FALSE;
124#endif
125
126   return GL_TRUE;
127}
128
129
130/**
131 * Error checking for glDrawElements().  Includes parameter checking
132 * and VBO bounds checking.
133 * \return GL_TRUE if OK to render, GL_FALSE if error found
134 */
135GLboolean
136_mesa_validate_DrawElements(GLcontext *ctx,
137			    GLenum mode, GLsizei count, GLenum type,
138			    const GLvoid *indices)
139{
140   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx,  GL_FALSE);
141
142   if (count <= 0) {
143      if (count < 0)
144	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawElements(count)" );
145      return GL_FALSE;
146   }
147
148   if (mode > GL_POLYGON) {
149      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(mode)" );
150      return GL_FALSE;
151   }
152
153   if (type != GL_UNSIGNED_INT &&
154       type != GL_UNSIGNED_BYTE &&
155       type != GL_UNSIGNED_SHORT)
156   {
157      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawElements(type)" );
158      return GL_FALSE;
159   }
160
161   if (ctx->NewState)
162      _mesa_update_state(ctx);
163
164   if (!check_valid_to_render(ctx, "Elements"))
165      return GL_FALSE;
166
167   /* Vertex buffer object tests */
168   if (_mesa_is_bufferobj(ctx->Array.ElementArrayBufferObj)) {
169      /* use indices in the buffer object */
170      /* make sure count doesn't go outside buffer bounds */
171      if (index_bytes(type, count) > ctx->Array.ElementArrayBufferObj->Size) {
172         _mesa_warning(ctx, "glDrawElements index out of buffer bounds");
173         return GL_FALSE;
174      }
175   }
176   else {
177      /* not using a VBO */
178      if (!indices)
179         return GL_FALSE;
180   }
181
182   if (ctx->Const.CheckArrayBounds) {
183      /* find max array index */
184      GLuint max = max_buffer_index(ctx, count, type, indices,
185                                    ctx->Array.ElementArrayBufferObj);
186      if (max >= ctx->Array.ArrayObj->_MaxElement) {
187         /* the max element is out of bounds of one or more enabled arrays */
188         _mesa_warning(ctx, "glDrawElements() index=%u is "
189                       "out of bounds (max=%u)", max, ctx->Array.ArrayObj->_MaxElement);
190         return GL_FALSE;
191      }
192   }
193
194   return GL_TRUE;
195}
196
197
198/**
199 * Error checking for glDrawRangeElements().  Includes parameter checking
200 * and VBO bounds checking.
201 * \return GL_TRUE if OK to render, GL_FALSE if error found
202 */
203GLboolean
204_mesa_validate_DrawRangeElements(GLcontext *ctx, GLenum mode,
205				 GLuint start, GLuint end,
206				 GLsizei count, GLenum type,
207				 const GLvoid *indices)
208{
209   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
210
211   if (count <= 0) {
212      if (count < 0)
213	 _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(count)" );
214      return GL_FALSE;
215   }
216
217   if (mode > GL_POLYGON) {
218      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(mode)" );
219      return GL_FALSE;
220   }
221
222   if (end < start) {
223      _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
224      return GL_FALSE;
225   }
226
227   if (type != GL_UNSIGNED_INT &&
228       type != GL_UNSIGNED_BYTE &&
229       type != GL_UNSIGNED_SHORT) {
230      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawRangeElements(type)" );
231      return GL_FALSE;
232   }
233
234   if (ctx->NewState)
235      _mesa_update_state(ctx);
236
237   if (!check_valid_to_render(ctx, "RangeElements"))
238      return GL_FALSE;
239
240   /* Vertex buffer object tests */
241   if (_mesa_is_bufferobj(ctx->Array.ElementArrayBufferObj)) {
242      /* use indices in the buffer object */
243      /* make sure count doesn't go outside buffer bounds */
244      if (index_bytes(type, count) > ctx->Array.ElementArrayBufferObj->Size) {
245         _mesa_warning(ctx, "glDrawRangeElements index out of buffer bounds");
246         return GL_FALSE;
247      }
248   }
249   else {
250      /* not using a VBO */
251      if (!indices)
252         return GL_FALSE;
253   }
254
255   if (ctx->Const.CheckArrayBounds) {
256      GLuint max = max_buffer_index(ctx, count, type, indices,
257                                    ctx->Array.ElementArrayBufferObj);
258      if (max >= ctx->Array.ArrayObj->_MaxElement) {
259         /* the max element is out of bounds of one or more enabled arrays */
260         return GL_FALSE;
261      }
262   }
263
264   return GL_TRUE;
265}
266
267
268/**
269 * Called from the tnl module to error check the function parameters and
270 * verify that we really can draw something.
271 * \return GL_TRUE if OK to render, GL_FALSE if error found
272 */
273GLboolean
274_mesa_validate_DrawArrays(GLcontext *ctx,
275			  GLenum mode, GLint start, GLsizei count)
276{
277   ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
278
279   if (count <= 0) {
280      if (count < 0)
281         _mesa_error(ctx, GL_INVALID_VALUE, "glDrawArrays(count)" );
282      return GL_FALSE;
283   }
284
285   if (mode > GL_POLYGON) {
286      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawArrays(mode)" );
287      return GL_FALSE;
288   }
289
290   if (ctx->NewState)
291      _mesa_update_state(ctx);
292
293   if (!check_valid_to_render(ctx, "Arrays"))
294      return GL_FALSE;
295
296   if (ctx->Const.CheckArrayBounds) {
297      if (start + count > (GLint) ctx->Array.ArrayObj->_MaxElement)
298         return GL_FALSE;
299   }
300
301   return GL_TRUE;
302}
303