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 "polygon.h"
  38 #include "mtypes.h"
  39
  40
  41 /**
  42  * Specify whether to cull front- or back-facing facets.
  43  *
  44  * \param mode culling mode.
  45  *
  46  * \sa glCullFace().
  47  *
  48  * Verifies the parameter and updates gl_polygon_attrib::CullFaceMode. On
  49  * change, flushes the vertices and notifies the driver via
  50  * the dd_function_table::CullFace callback.
  51  */
  52 void GLAPIENTRY
  53 _mesa_CullFace( GLenum mode )
  54 {
  55    GET_CURRENT_CONTEXT(ctx);
  56    ASSERT_OUTSIDE_BEGIN_END(ctx);
  57
  58    if (MESA_VERBOSE&VERBOSE_API)
  59       _mesa_debug(ctx, "glCullFace %s\n", _mesa_lookup_enum_by_nr(mode));
  60
  61    if (mode!=GL_FRONT && mode!=GL_BACK && mode!=GL_FRONT_AND_BACK) {
  62       _mesa_error( ctx, GL_INVALID_ENUM, "glCullFace" );
  63       return;
  64    }
  65
  66    if (ctx->Polygon.CullFaceMode == mode)
  67       return;
  68
  69    FLUSH_VERTICES(ctx, _NEW_POLYGON);
  70    ctx->Polygon.CullFaceMode = mode;
  71
  72    if (ctx->Driver.CullFace)
  73       ctx->Driver.CullFace( ctx, mode );
  74 }
  75
  76
  77 /**
  78  * Define front- and back-facing
  79  *
  80  * \param mode orientation of front-facing polygons.
  81  *
  82  * \sa glFrontFace().
  83  *
  84  * Verifies the parameter and updates gl_polygon_attrib::FrontFace. On change
  85  * flushes the vertices and notifies the driver via
  86  * the dd_function_table::FrontFace callback.
  87  */
  88 void GLAPIENTRY
  89 _mesa_FrontFace( GLenum mode )
  90 {
  91    GET_CURRENT_CONTEXT(ctx);
  92    ASSERT_OUTSIDE_BEGIN_END(ctx);
  93
  94    if (MESA_VERBOSE&VERBOSE_API)
  95       _mesa_debug(ctx, "glFrontFace %s\n", _mesa_lookup_enum_by_nr(mode));
  96
  97    if (mode!=GL_CW && mode!=GL_CCW) {
  98       _mesa_error( ctx, GL_INVALID_ENUM, "glFrontFace" );
  99       return;
 100    }
 101
 102    if (ctx->Polygon.FrontFace == mode)
 103       return;
 104
 105    FLUSH_VERTICES(ctx, _NEW_POLYGON);
 106    ctx->Polygon.FrontFace = mode;
 107
 108    ctx->Polygon._FrontBit = (GLboolean) (mode == GL_CW);
 109
 110    if (ctx->Driver.FrontFace)
 111       ctx->Driver.FrontFace( ctx, mode );
 112 }
 113
 114
 115 /**
 116  * Set the polygon rasterization mode.
 117  *
 118  * \param face the polygons which \p mode applies to.
 119  * \param mode how polygons should be rasterized.
 120  *
 121  * \sa glPolygonMode().
 122  *
 123  * Verifies the parameters and updates gl_polygon_attrib::FrontMode and
 124  * gl_polygon_attrib::BackMode. On change flushes the vertices and notifies the
 125  * driver via the dd_function_table::PolygonMode callback.
 126  */
 127 void GLAPIENTRY
 128 _mesa_PolygonMode( GLenum face, GLenum mode )
 129 {
 130    GET_CURRENT_CONTEXT(ctx);
 131    ASSERT_OUTSIDE_BEGIN_END(ctx);
 132
 133    if (MESA_VERBOSE&VERBOSE_API)
 134       _mesa_debug(ctx, "glPolygonMode %s %s\n",
 135                   _mesa_lookup_enum_by_nr(face),
 136                   _mesa_lookup_enum_by_nr(mode));
 137
 138    if (mode!=GL_POINT && mode!=GL_LINE && mode!=GL_FILL) {
 139       _mesa_error( ctx, GL_INVALID_ENUM, "glPolygonMode(mode)" );
 140       return;
 141    }
 142
 143    switch (face) {
 144    case GL_FRONT:
 145       if (ctx->Polygon.FrontMode == mode)
 146          return;
 147       FLUSH_VERTICES(ctx, _NEW_POLYGON);
 148       ctx->Polygon.FrontMode = mode;
 149       break;
 150    case GL_FRONT_AND_BACK:
 151       if (ctx->Polygon.FrontMode == mode &&
 152           ctx->Polygon.BackMode == mode)
 153          return;
 154       FLUSH_VERTICES(ctx, _NEW_POLYGON);
 155       ctx->Polygon.FrontMode = mode;
 156       ctx->Polygon.BackMode = mode;
 157       break;
 158    case GL_BACK:
 159       if (ctx->Polygon.BackMode == mode)
 160          return;
 161       FLUSH_VERTICES(ctx, _NEW_POLYGON);
 162       ctx->Polygon.BackMode = mode;
 163       break;
 164    default:
 165       _mesa_error( ctx, GL_INVALID_ENUM, "glPolygonMode(face)" );
 166       return;
 167    }
 168
 169    if (ctx->Polygon.FrontMode == GL_FILL && ctx->Polygon.BackMode == GL_FILL)
 170       ctx->_TriangleCaps &= ~DD_TRI_UNFILLED;
 171    else
 172       ctx->_TriangleCaps |= DD_TRI_UNFILLED;
 173
 174    if (ctx->Driver.PolygonMode)
 175       ctx->Driver.PolygonMode(ctx, face, mode);
 176 }
 177
 178 #if _HAVE_FULL_GL
 179
 180
 181 /**
 182  * This routine updates the ctx->Polygon.Stipple state.
 183  * If we're getting the stipple data from a PBO, we map the buffer
 184  * in order to access the data.
 185  * In any case, we obey the current pixel unpacking parameters when fetching
 186  * the stipple data.
 187  *
 188  * In the future, this routine should be used as a fallback, called via
 189  * ctx->Driver.PolygonStipple().  We'll have to update all the DRI drivers
 190  * too.
 191  */
 192 void
 193 _mesa_polygon_stipple(GLcontext *ctx, const GLubyte *pattern)
 194 {
 195    pattern = _mesa_map_validate_pbo_source(ctx, 2,
 196                                            &ctx->Unpack, 32, 32, 1,
 197                                            GL_COLOR_INDEX, GL_BITMAP, pattern,
 198                                            "glPolygonStipple");
 199    if (!pattern)
 200       return;
 201
 202    _mesa_unpack_polygon_stipple(pattern, ctx->PolygonStipple, &ctx->Unpack);
 203
 204    _mesa_unmap_pbo_source(ctx, &ctx->Unpack);
 205 }
 206
 207
 208 /**
 209  * Called by glPolygonStipple.
 210  */
 211 void GLAPIENTRY
 212 _mesa_PolygonStipple( const GLubyte *pattern )
 213 {
 214    GET_CURRENT_CONTEXT(ctx);
 215    ASSERT_OUTSIDE_BEGIN_END(ctx);
 216
 217    if (MESA_VERBOSE&VERBOSE_API)
 218       _mesa_debug(ctx, "glPolygonStipple\n");
 219
 220    FLUSH_VERTICES(ctx, _NEW_POLYGONSTIPPLE);
 221
 222    _mesa_polygon_stipple(ctx, pattern);
 223
 224    if (ctx->Driver.PolygonStipple)
 225       ctx->Driver.PolygonStipple(ctx, pattern);
 226 }
 227
 228
 229 /**
 230  * Called by glPolygonStipple.
 231  */
 232 void GLAPIENTRY
 233 _mesa_GetPolygonStipple( GLubyte *dest )
 234 {
 235    GET_CURRENT_CONTEXT(ctx);
 236    ASSERT_OUTSIDE_BEGIN_END(ctx);
 237
 238    if (MESA_VERBOSE&VERBOSE_API)
 239       _mesa_debug(ctx, "glGetPolygonStipple\n");
 240
 241    dest = _mesa_map_validate_pbo_dest(ctx, 2,
 242                                       &ctx->Pack, 32, 32, 1,
 243                                       GL_COLOR_INDEX, GL_BITMAP, dest,
 244                                       "glGetPolygonStipple");
 245    if (!dest)
 246       return;
 247
 248    _mesa_pack_polygon_stipple(ctx->PolygonStipple, dest, &ctx->Pack);
 249
 250    _mesa_unmap_pbo_dest(ctx, &ctx->Pack);
 251 }
 252
 253
 254 void GLAPIENTRY
 255 _mesa_PolygonOffset( GLfloat factor, GLfloat units )
 256 {
 257    GET_CURRENT_CONTEXT(ctx);
 258    ASSERT_OUTSIDE_BEGIN_END(ctx);
 259
 260    if (MESA_VERBOSE&VERBOSE_API)
 261       _mesa_debug(ctx, "glPolygonOffset %f %f\n", factor, units);
 262
 263    if (ctx->Polygon.OffsetFactor == factor &&
 264        ctx->Polygon.OffsetUnits == units)
 265       return;
 266
 267    FLUSH_VERTICES(ctx, _NEW_POLYGON);
 268    ctx->Polygon.OffsetFactor = factor;
 269    ctx->Polygon.OffsetUnits = units;
 270
 271    if (ctx->Driver.PolygonOffset)
 272       ctx->Driver.PolygonOffset( ctx, factor, units );
 273 }
 274
 275
 276 void GLAPIENTRY
 277 _mesa_PolygonOffsetEXT( GLfloat factor, GLfloat bias )
 278 {
 279    GET_CURRENT_CONTEXT(ctx);
 280    /* XXX mult by DepthMaxF here??? */
 281    _mesa_PolygonOffset(factor, bias * ctx->DrawBuffer->_DepthMaxF );
 282 }
 283
 284 #endif
 285
 286
 287 /**********************************************************************/
 288 /** \name Initialization */
 289 /*@{*/
 290
 291 /**
 292  * Initialize the context polygon state.
 293  *
 294  * \param ctx GL context.
 295  *
 296  * Initializes __GLcontextRec::Polygon and __GLcontextRec::PolygonStipple
 297  * attribute groups.
 298  */
 299 void _mesa_init_polygon( GLcontext * ctx )
 300 {
 301    /* Polygon group */
 302    ctx->Polygon.CullFlag = GL_FALSE;
 303    ctx->Polygon.CullFaceMode = GL_BACK;
 304    ctx->Polygon.FrontFace = GL_CCW;
 305    ctx->Polygon._FrontBit = 0;
 306    ctx->Polygon.FrontMode = GL_FILL;
 307    ctx->Polygon.BackMode = GL_FILL;
 308    ctx->Polygon.SmoothFlag = GL_FALSE;
 309    ctx->Polygon.StippleFlag = GL_FALSE;
 310    ctx->Polygon.OffsetFactor = 0.0F;
 311    ctx->Polygon.OffsetUnits = 0.0F;
 312    ctx->Polygon.OffsetPoint = GL_FALSE;
 313    ctx->Polygon.OffsetLine = GL_FALSE;
 314    ctx->Polygon.OffsetFill = GL_FALSE;
 315
 316
 317    /* Polygon Stipple group */
 318    memset( ctx->PolygonStipple, 0xff, 32*sizeof(GLuint) );
 319 }
 320
 321 /*@}*/