polygon.c revision 7117f1b4 
1/**
2 * \file polygon.c
3 * Polygon operations.
4 */
5
6/*
7 * Mesa 3-D graphics library
8 * Version:  6.5.1
9 *
10 * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
11 *
12 * Permission is hereby granted, free of charge, to any person obtaining a
13 * copy of this software and associated documentation files (the "Software"),
14 * to deal in the Software without restriction, including without limitation
15 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
16 * and/or sell copies of the Software, and to permit persons to whom the
17 * Software is furnished to do so, subject to the following conditions:
18 *
19 * The above copyright notice and this permission notice shall be included
20 * in all copies or substantial portions of the Software.
21 *
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
23 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
25 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
26 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
27 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
28 */
29
30
31#include "glheader.h"
32#include "imports.h"
33#include "bufferobj.h"
34#include "context.h"
35#include "image.h"
36#include "enums.h"
37#include "macros.h"
38#include "polygon.h"
39#include "mtypes.h"
40
41
42/**
43 * Specify whether to cull front- or back-facing facets.
44 *
45 * \param mode culling mode.
46 *
47 * \sa glCullFace().
48 *
49 * Verifies the parameter and updates gl_polygon_attrib::CullFaceMode. On
50 * change, flushes the vertices and notifies the driver via
51 * the dd_function_table::CullFace callback.
52 */
53void GLAPIENTRY
54_mesa_CullFace( GLenum mode )
55{
56   GET_CURRENT_CONTEXT(ctx);
57   ASSERT_OUTSIDE_BEGIN_END(ctx);
58
59   if (MESA_VERBOSE&VERBOSE_API)
60      _mesa_debug(ctx, "glCullFace %s\n", _mesa_lookup_enum_by_nr(mode));
61
62   if (mode!=GL_FRONT && mode!=GL_BACK && mode!=GL_FRONT_AND_BACK) {
63      _mesa_error( ctx, GL_INVALID_ENUM, "glCullFace" );
64      return;
65   }
66
67   if (ctx->Polygon.CullFaceMode == mode)
68      return;
69
70   FLUSH_VERTICES(ctx, _NEW_POLYGON);
71   ctx->Polygon.CullFaceMode = mode;
72
73   if (ctx->Driver.CullFace)
74      ctx->Driver.CullFace( ctx, mode );
75}
76
77
78/**
79 * Define front- and back-facing
80 *
81 * \param mode orientation of front-facing polygons.
82 *
83 * \sa glFrontFace().
84 *
85 * Verifies the parameter and updates gl_polygon_attrib::FrontFace. On change
86 * flushes the vertices and notifies the driver via
87 * the dd_function_table::FrontFace callback.
88 */
89void GLAPIENTRY
90_mesa_FrontFace( GLenum mode )
91{
92   GET_CURRENT_CONTEXT(ctx);
93   ASSERT_OUTSIDE_BEGIN_END(ctx);
94
95   if (MESA_VERBOSE&VERBOSE_API)
96      _mesa_debug(ctx, "glFrontFace %s\n", _mesa_lookup_enum_by_nr(mode));
97
98   if (mode!=GL_CW && mode!=GL_CCW) {
99      _mesa_error( ctx, GL_INVALID_ENUM, "glFrontFace" );
100      return;
101   }
102
103   if (ctx->Polygon.FrontFace == mode)
104      return;
105
106   FLUSH_VERTICES(ctx, _NEW_POLYGON);
107   ctx->Polygon.FrontFace = mode;
108
109   ctx->Polygon._FrontBit = (GLboolean) (mode == GL_CW);
110
111   if (ctx->Driver.FrontFace)
112      ctx->Driver.FrontFace( ctx, mode );
113}
114
115
116/**
117 * Set the polygon rasterization mode.
118 *
119 * \param face the polygons which \p mode applies to.
120 * \param mode how polygons should be rasterized.
121 *
122 * \sa glPolygonMode().
123 *
124 * Verifies the parameters and updates gl_polygon_attrib::FrontMode and
125 * gl_polygon_attrib::BackMode. On change flushes the vertices and notifies the
126 * driver via the dd_function_table::PolygonMode callback.
127 */
128void GLAPIENTRY
129_mesa_PolygonMode( GLenum face, GLenum mode )
130{
131   GET_CURRENT_CONTEXT(ctx);
132   ASSERT_OUTSIDE_BEGIN_END(ctx);
133
134   if (MESA_VERBOSE&VERBOSE_API)
135      _mesa_debug(ctx, "glPolygonMode %s %s\n",
136                  _mesa_lookup_enum_by_nr(face),
137                  _mesa_lookup_enum_by_nr(mode));
138
139   if (mode!=GL_POINT && mode!=GL_LINE && mode!=GL_FILL) {
140      _mesa_error( ctx, GL_INVALID_ENUM, "glPolygonMode(mode)" );
141      return;
142   }
143
144   switch (face) {
145   case GL_FRONT:
146      if (ctx->Polygon.FrontMode == mode)
147	 return;
148      FLUSH_VERTICES(ctx, _NEW_POLYGON);
149      ctx->Polygon.FrontMode = mode;
150      break;
151   case GL_FRONT_AND_BACK:
152      if (ctx->Polygon.FrontMode == mode &&
153	  ctx->Polygon.BackMode == mode)
154	 return;
155      FLUSH_VERTICES(ctx, _NEW_POLYGON);
156      ctx->Polygon.FrontMode = mode;
157      ctx->Polygon.BackMode = mode;
158      break;
159   case GL_BACK:
160      if (ctx->Polygon.BackMode == mode)
161	 return;
162      FLUSH_VERTICES(ctx, _NEW_POLYGON);
163      ctx->Polygon.BackMode = mode;
164      break;
165   default:
166      _mesa_error( ctx, GL_INVALID_ENUM, "glPolygonMode(face)" );
167      return;
168   }
169
170   if (ctx->Polygon.FrontMode == GL_FILL && ctx->Polygon.BackMode == GL_FILL)
171      ctx->_TriangleCaps &= ~DD_TRI_UNFILLED;
172   else
173      ctx->_TriangleCaps |= DD_TRI_UNFILLED;
174
175   if (ctx->Driver.PolygonMode)
176      ctx->Driver.PolygonMode(ctx, face, mode);
177}
178
179#if _HAVE_FULL_GL
180
181
182/**
183 * This routine updates the ctx->Polygon.Stipple state.
184 * If we're getting the stipple data from a PBO, we map the buffer
185 * in order to access the data.
186 * In any case, we obey the current pixel unpacking parameters when fetching
187 * the stipple data.
188 *
189 * In the future, this routine should be used as a fallback, called via
190 * ctx->Driver.PolygonStipple().  We'll have to update all the DRI drivers
191 * too.
192 */
193void
194_mesa_polygon_stipple(GLcontext *ctx, const GLubyte *pattern)
195{
196   if (ctx->Unpack.BufferObj->Name) {
197      /* Get/unpack the stipple pattern from a PBO */
198      GLubyte *buf;
199      if (!_mesa_validate_pbo_access(2, &ctx->Unpack, 32, 32, 1,
200                                     GL_COLOR_INDEX, GL_BITMAP, pattern)) {
201         _mesa_error(ctx, GL_INVALID_OPERATION,
202                     "glPolygonStipple(bad PBO access)");
203         return;
204      }
205      buf = (GLubyte *) ctx->Driver.MapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
206                                              GL_READ_ONLY_ARB,
207                                              ctx->Unpack.BufferObj);
208      if (!buf) {
209         _mesa_error(ctx, GL_INVALID_OPERATION,
210                     "glPolygonStipple(PBO mapped)");
211         return;
212      }
213      buf = ADD_POINTERS(buf, pattern);
214      _mesa_unpack_polygon_stipple(buf, ctx->PolygonStipple, &ctx->Unpack);
215      ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_UNPACK_BUFFER_EXT,
216                              ctx->Unpack.BufferObj);
217   }
218   else {
219      /* Get/unpack the stipple pattern from user memory */
220      _mesa_unpack_polygon_stipple(pattern, ctx->PolygonStipple, &ctx->Unpack);
221   }
222}
223
224
225/**
226 * Called by glPolygonStipple.
227 */
228void GLAPIENTRY
229_mesa_PolygonStipple( const GLubyte *pattern )
230{
231   GET_CURRENT_CONTEXT(ctx);
232   ASSERT_OUTSIDE_BEGIN_END(ctx);
233
234   if (MESA_VERBOSE&VERBOSE_API)
235      _mesa_debug(ctx, "glPolygonStipple\n");
236
237   FLUSH_VERTICES(ctx, _NEW_POLYGONSTIPPLE);
238
239   _mesa_polygon_stipple(ctx, pattern);
240
241   if (ctx->Driver.PolygonStipple)
242      ctx->Driver.PolygonStipple(ctx, pattern);
243}
244
245
246/**
247 * Called by glPolygonStipple.
248 */
249void GLAPIENTRY
250_mesa_GetPolygonStipple( GLubyte *dest )
251{
252   GET_CURRENT_CONTEXT(ctx);
253   ASSERT_OUTSIDE_BEGIN_END(ctx);
254
255   if (MESA_VERBOSE&VERBOSE_API)
256      _mesa_debug(ctx, "glGetPolygonStipple\n");
257
258   /* XXX someday we may put this code into a separate function and call
259    * it with ctx->Driver.GetPolygonStipple().
260    */
261   if (ctx->Pack.BufferObj->Name) {
262      /* Put/pack the stipple pattern into a PBO */
263      GLubyte *buf;
264      if (!_mesa_validate_pbo_access(2, &ctx->Pack, 32, 32, 1,
265                                     GL_COLOR_INDEX, GL_BITMAP, dest)) {
266         _mesa_error(ctx, GL_INVALID_OPERATION,
267                     "glGetPolygonStipple(bad PBO access)");
268         return;
269      }
270      buf = (GLubyte *) ctx->Driver.MapBuffer(ctx, GL_PIXEL_PACK_BUFFER_EXT,
271                                              GL_WRITE_ONLY_ARB,
272                                              ctx->Pack.BufferObj);
273      if (!buf) {
274         _mesa_error(ctx, GL_INVALID_OPERATION,
275                     "glGetPolygonStipple(PBO mapped)");
276         return;
277      }
278      buf = ADD_POINTERS(buf, dest);
279      _mesa_pack_polygon_stipple(ctx->PolygonStipple, buf, &ctx->Pack);
280      ctx->Driver.UnmapBuffer(ctx, GL_PIXEL_PACK_BUFFER_EXT,
281                              ctx->Pack.BufferObj);
282   }
283   else {
284      /* Put/pack the stipple pattern into user memory */
285      _mesa_pack_polygon_stipple(ctx->PolygonStipple, dest, &ctx->Pack);
286   }
287}
288
289
290void GLAPIENTRY
291_mesa_PolygonOffset( GLfloat factor, GLfloat units )
292{
293   GET_CURRENT_CONTEXT(ctx);
294   ASSERT_OUTSIDE_BEGIN_END(ctx);
295
296   if (MESA_VERBOSE&VERBOSE_API)
297      _mesa_debug(ctx, "glPolygonOffset %f %f\n", factor, units);
298
299   if (ctx->Polygon.OffsetFactor == factor &&
300       ctx->Polygon.OffsetUnits == units)
301      return;
302
303   FLUSH_VERTICES(ctx, _NEW_POLYGON);
304   ctx->Polygon.OffsetFactor = factor;
305   ctx->Polygon.OffsetUnits = units;
306
307   if (ctx->Driver.PolygonOffset)
308      ctx->Driver.PolygonOffset( ctx, factor, units );
309}
310
311
312void GLAPIENTRY
313_mesa_PolygonOffsetEXT( GLfloat factor, GLfloat bias )
314{
315   GET_CURRENT_CONTEXT(ctx);
316   /* XXX mult by DepthMaxF here??? */
317   _mesa_PolygonOffset(factor, bias * ctx->DrawBuffer->_DepthMaxF );
318}
319
320#endif
321
322
323/**********************************************************************/
324/** \name Initialization */
325/*@{*/
326
327/**
328 * Initialize the context polygon state.
329 *
330 * \param ctx GL context.
331 *
332 * Initializes __GLcontextRec::Polygon and __GLcontextRec::PolygonStipple
333 * attribute groups.
334 */
335void _mesa_init_polygon( GLcontext * ctx )
336{
337   /* Polygon group */
338   ctx->Polygon.CullFlag = GL_FALSE;
339   ctx->Polygon.CullFaceMode = GL_BACK;
340   ctx->Polygon.FrontFace = GL_CCW;
341   ctx->Polygon._FrontBit = 0;
342   ctx->Polygon.FrontMode = GL_FILL;
343   ctx->Polygon.BackMode = GL_FILL;
344   ctx->Polygon.SmoothFlag = GL_FALSE;
345   ctx->Polygon.StippleFlag = GL_FALSE;
346   ctx->Polygon.OffsetFactor = 0.0F;
347   ctx->Polygon.OffsetUnits = 0.0F;
348   ctx->Polygon.OffsetPoint = GL_FALSE;
349   ctx->Polygon.OffsetLine = GL_FALSE;
350   ctx->Polygon.OffsetFill = GL_FALSE;
351
352
353   /* Polygon Stipple group */
354   MEMSET( ctx->PolygonStipple, 0xff, 32*sizeof(GLuint) );
355}
356
357/*@}*/
358