formatquery.c revision 848b8605 
1/*
2 * Copyright © 2012 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 */
23
24#include "mtypes.h"
25#include "context.h"
26#include "glformats.h"
27#include "macros.h"
28#include "enums.h"
29#include "fbobject.h"
30#include "formatquery.h"
31
32/* default implementation of QuerySamplesForFormat driverfunc, for
33 * non-multisample-capable drivers. */
34size_t
35_mesa_query_samples_for_format(struct gl_context *ctx, GLenum target,
36                               GLenum internalFormat, int samples[16])
37{
38   (void) target;
39   (void) internalFormat;
40   (void) ctx;
41
42   samples[0] = 1;
43   return 1;
44}
45
46
47void GLAPIENTRY
48_mesa_GetInternalformativ(GLenum target, GLenum internalformat, GLenum pname,
49                          GLsizei bufSize, GLint *params)
50{
51   GLint buffer[16];
52   GLsizei count = 0;
53   GET_CURRENT_CONTEXT(ctx);
54
55   ASSERT_OUTSIDE_BEGIN_END(ctx);
56
57   if (!ctx->Extensions.ARB_internalformat_query) {
58      _mesa_error(ctx, GL_INVALID_OPERATION, "glGetInternalformativ");
59      return;
60   }
61
62   assert(ctx->Driver.QuerySamplesForFormat != NULL);
63
64   /* The ARB_internalformat_query spec says:
65    *
66    *     "If the <target> parameter to GetInternalformativ is not one of
67    *     TEXTURE_2D_MULTISAMPLE, TEXTURE_2D_MULTISAMPLE_ARRAY or RENDERBUFFER
68    *     then an INVALID_ENUM error is generated."
69    */
70   switch (target) {
71   case GL_RENDERBUFFER:
72      break;
73
74   case GL_TEXTURE_2D_MULTISAMPLE:
75   case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
76      /* These enums are only valid if ARB_texture_multisample is supported */
77      if (_mesa_is_desktop_gl(ctx) && ctx->Extensions.ARB_texture_multisample)
78         break;
79
80   default:
81      _mesa_error(ctx, GL_INVALID_ENUM,
82                  "glGetInternalformativ(target=%s)",
83                  _mesa_lookup_enum_by_nr(target));
84      return;
85   }
86
87   /* The ARB_internalformat_query spec says:
88    *
89    *     "If the <internalformat> parameter to GetInternalformativ is not
90    *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
91    *     generated."
92    */
93   if (_mesa_base_fbo_format(ctx, internalformat) == 0) {
94      _mesa_error(ctx, GL_INVALID_ENUM,
95                  "glGetInternalformativ(internalformat=%s)",
96                  _mesa_lookup_enum_by_nr(internalformat));
97      return;
98   }
99
100   /* The ARB_internalformat_query spec says:
101    *
102    *     "If the <bufSize> parameter to GetInternalformativ is negative, then
103    *     an INVALID_VALUE error is generated."
104    */
105   if (bufSize < 0) {
106      _mesa_error(ctx, GL_INVALID_VALUE,
107                  "glGetInternalformativ(target=%s)",
108                  _mesa_lookup_enum_by_nr(target));
109      return;
110   }
111
112   switch (pname) {
113   case GL_SAMPLES:
114      count = ctx->Driver.QuerySamplesForFormat(ctx, target,
115            internalformat, buffer);
116      break;
117   case GL_NUM_SAMPLE_COUNTS: {
118      /* The driver can return 0, and we should pass that along to the
119       * application.  The ARB decided that ARB_internalformat_query should
120       * behave as ARB_internalformat_query2 in this situation.
121       *
122       * The ARB_internalformat_query2 spec says:
123       *
124       *     "- NUM_SAMPLE_COUNTS: The number of sample counts that would be
125       *        returned by querying SAMPLES is returned in <params>.
126       *        * If <internalformat> is not color-renderable,
127       *          depth-renderable, or stencil-renderable (as defined in
128       *          section 4.4.4), or if <target> does not support multiple
129       *          samples (ie other than TEXTURE_2D_MULTISAMPLE,
130       *          TEXTURE_2D_MULTISAMPLE_ARRAY, or RENDERBUFFER), 0 is
131       *          returned."
132       */
133      const size_t num_samples =
134         ctx->Driver.QuerySamplesForFormat(ctx, target, internalformat, buffer);
135
136      /* QuerySamplesForFormat writes some stuff to buffer, so we have to
137       * separately over-write it with the requested value.
138       */
139      buffer[0] = (GLint) num_samples;
140      count = 1;
141      break;
142   }
143   default:
144      _mesa_error(ctx, GL_INVALID_ENUM,
145                  "glGetInternalformativ(pname=%s)",
146                  _mesa_lookup_enum_by_nr(pname));
147      return;
148   }
149
150   if (bufSize != 0 && params == NULL) {
151      /* Emit a warning to aid application debugging, but go ahead and do the
152       * memcpy (and probably crash) anyway.
153       */
154      _mesa_warning(ctx,
155                    "glGetInternalformativ(bufSize = %d, but params = NULL)",
156                    bufSize);
157   }
158
159   /* Copy the data from the temporary buffer to the buffer supplied by the
160    * application.  Clamp the size of the copy to the size supplied by the
161    * application.
162    */
163   memcpy(params, buffer, MIN2(count, bufSize) * sizeof(GLint));
164
165   return;
166}
167