src/mesa/main/polygon.c

   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  */
  53 void 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  */
  89 void 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  */
 128 void 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  */
 193 void
 194 _mesa_polygon_stipple(GLcontext *ctx, const GLubyte *pattern)
 195 {
 196    pattern = _mesa_map_validate_pbo_source(ctx, 2,
 197                                            &ctx->Unpack, 32, 32, 1,
 198                                            GL_COLOR_INDEX, GL_BITMAP, pattern,
 199                                            "glPolygonStipple");
 200    if (!pattern)
 201       return;
 202
 203    _mesa_unpack_polygon_stipple(pattern, ctx->PolygonStipple, &ctx->Unpack);
 204
 205    _mesa_unmap_pbo_source(ctx, &ctx->Unpack);
 206 }
 207
 208
 209 /**
 210  * Called by glPolygonStipple.
 211  */
 212 void GLAPIENTRY
 213 _mesa_PolygonStipple( const GLubyte *pattern )
 214 {
 215    GET_CURRENT_CONTEXT(ctx);
 216    ASSERT_OUTSIDE_BEGIN_END(ctx);
 217
 218    if (MESA_VERBOSE&VERBOSE_API)
 219       _mesa_debug(ctx, "glPolygonStipple\n");
 220
 221    FLUSH_VERTICES(ctx, _NEW_POLYGONSTIPPLE);
 222
 223    _mesa_polygon_stipple(ctx, pattern);
 224
 225    if (ctx->Driver.PolygonStipple)
 226       ctx->Driver.PolygonStipple(ctx, pattern);
 227 }
 228
 229
 230 /**
 231  * Called by glPolygonStipple.
 232  */
 233 void GLAPIENTRY
 234 _mesa_GetPolygonStipple( GLubyte *dest )
 235 {
 236    GET_CURRENT_CONTEXT(ctx);
 237    ASSERT_OUTSIDE_BEGIN_END(ctx);
 238
 239    if (MESA_VERBOSE&VERBOSE_API)
 240       _mesa_debug(ctx, "glGetPolygonStipple\n");
 241
 242    dest = _mesa_map_validate_pbo_dest(ctx, 2,
 243                                       &ctx->Pack, 32, 32, 1,
 244                                       GL_COLOR_INDEX, GL_BITMAP, dest,
 245                                       "glGetPolygonStipple");
 246    if (!dest)
 247       return;
 248
 249    _mesa_pack_polygon_stipple(ctx->PolygonStipple, dest, &ctx->Pack);
 250
 251    _mesa_unmap_pbo_dest(ctx, &ctx->Pack);
 252 }
 253
 254
 255 void GLAPIENTRY
 256 _mesa_PolygonOffset( GLfloat factor, GLfloat units )
 257 {
 258    GET_CURRENT_CONTEXT(ctx);
 259    ASSERT_OUTSIDE_BEGIN_END(ctx);
 260
 261    if (MESA_VERBOSE&VERBOSE_API)
 262       _mesa_debug(ctx, "glPolygonOffset %f %f\n", factor, units);
 263
 264    if (ctx->Polygon.OffsetFactor == factor &&
 265        ctx->Polygon.OffsetUnits == units)
 266       return;
 267
 268    FLUSH_VERTICES(ctx, _NEW_POLYGON);
 269    ctx->Polygon.OffsetFactor = factor;
 270    ctx->Polygon.OffsetUnits = units;
 271
 272    if (ctx->Driver.PolygonOffset)
 273       ctx->Driver.PolygonOffset( ctx, factor, units );
 274 }
 275
 276
 277 void GLAPIENTRY
 278 _mesa_PolygonOffsetEXT( GLfloat factor, GLfloat bias )
 279 {
 280    GET_CURRENT_CONTEXT(ctx);
 281    /* XXX mult by DepthMaxF here??? */
 282    _mesa_PolygonOffset(factor, bias * ctx->DrawBuffer->_DepthMaxF );
 283 }
 284
 285 #endif
 286
 287
 288 /**********************************************************************/
 289 /** \name Initialization */
 290 /*@{*/
 291
 292 /**
 293  * Initialize the context polygon state.
 294  *
 295  * \param ctx GL context.
 296  *
 297  * Initializes __GLcontextRec::Polygon and __GLcontextRec::PolygonStipple
 298  * attribute groups.
 299  */
 300 void _mesa_init_polygon( GLcontext * ctx )
 301 {
 302    /* Polygon group */
 303    ctx->Polygon.CullFlag = GL_FALSE;
 304    ctx->Polygon.CullFaceMode = GL_BACK;
 305    ctx->Polygon.FrontFace = GL_CCW;
 306    ctx->Polygon._FrontBit = 0;
 307    ctx->Polygon.FrontMode = GL_FILL;
 308    ctx->Polygon.BackMode = GL_FILL;
 309    ctx->Polygon.SmoothFlag = GL_FALSE;
 310    ctx->Polygon.StippleFlag = GL_FALSE;
 311    ctx->Polygon.OffsetFactor = 0.0F;
 312    ctx->Polygon.OffsetUnits = 0.0F;
 313    ctx->Polygon.OffsetPoint = GL_FALSE;
 314    ctx->Polygon.OffsetLine = GL_FALSE;
 315    ctx->Polygon.OffsetFill = GL_FALSE;
 316
 317
 318    /* Polygon Stipple group */
 319    MEMSET( ctx->PolygonStipple, 0xff, 32*sizeof(GLuint) );
 320 }
 321
 322 /*@}*/