src/mesa/main/points.c

   1 /**
   2  * \file points.c
   3  * Point operations.
   4  */
   5
   6 /*
   7  * Mesa 3-D graphics library
   8  * Version:  7.1
   9  *
  10  * Copyright (C) 1999-2007  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 "context.h"
  33 #include "macros.h"
  34 #include "points.h"
  35 #include "mtypes.h"
  36
  37
  38 /**
  39  * Set current point size.
  40  * \param size  point diameter in pixels
  41  * \sa glPointSize().
  42  */
  43 void GLAPIENTRY
  44 _mesa_PointSize( GLfloat size )
  45 {
  46    GET_CURRENT_CONTEXT(ctx);
  47
  48    if (size <= 0.0) {
  49       _mesa_error( ctx, GL_INVALID_VALUE, "glPointSize" );
  50       return;
  51    }
  52
  53    if (ctx->Point.Size == size)
  54       return;
  55
  56    FLUSH_VERTICES(ctx, _NEW_POINT);
  57    ctx->Point.Size = size;
  58
  59    if (ctx->Driver.PointSize)
  60       ctx->Driver.PointSize(ctx, size);
  61 }
  62
  63
  64 void GLAPIENTRY
  65 _mesa_PointParameteri( GLenum pname, GLint param )
  66 {
  67    GLfloat p[3];
  68    p[0] = (GLfloat) param;
  69    p[1] = p[2] = 0.0F;
  70    _mesa_PointParameterfv(pname, p);
  71 }
  72
  73
  74 void GLAPIENTRY
  75 _mesa_PointParameteriv( GLenum pname, const GLint *params )
  76 {
  77    GLfloat p[3];
  78    p[0] = (GLfloat) params[0];
  79    if (pname == GL_DISTANCE_ATTENUATION_EXT) {
  80       p[1] = (GLfloat) params[1];
  81       p[2] = (GLfloat) params[2];
  82    }
  83    _mesa_PointParameterfv(pname, p);
  84 }
  85
  86
  87 void GLAPIENTRY
  88 _mesa_PointParameterf( GLenum pname, GLfloat param)
  89 {
  90    GLfloat p[3];
  91    p[0] = param;
  92    p[1] = p[2] = 0.0F;
  93    _mesa_PointParameterfv(pname, p);
  94 }
  95
  96
  97 void GLAPIENTRY
  98 _mesa_PointParameterfv( GLenum pname, const GLfloat *params)
  99 {
 100    GET_CURRENT_CONTEXT(ctx);
 101
 102    /* Drivers that support point sprites must also support point parameters.
 103     * If point parameters aren't supported, then this function shouldn't even
 104     * exist.
 105     */
 106    ASSERT(!(ctx->Extensions.ARB_point_sprite
 107             || ctx->Extensions.NV_point_sprite)
 108           || ctx->Extensions.EXT_point_parameters);
 109
 110    if (!ctx->Extensions.EXT_point_parameters) {
 111       _mesa_error(ctx, GL_INVALID_OPERATION,
 112                   "unsupported function called (unsupported extension)");
 113       return;
 114    }
 115
 116    switch (pname) {
 117       case GL_DISTANCE_ATTENUATION_EXT:
 118          if (TEST_EQ_3V(ctx->Point.Params, params))
 119             return;
 120          FLUSH_VERTICES(ctx, _NEW_POINT);
 121          COPY_3V(ctx->Point.Params, params);
 122          ctx->Point._Attenuated = (ctx->Point.Params[0] != 1.0 ||
 123                                    ctx->Point.Params[1] != 0.0 ||
 124                                    ctx->Point.Params[2] != 0.0);
 125
 126          if (ctx->Point._Attenuated)
 127             ctx->_TriangleCaps |= DD_POINT_ATTEN;
 128          else
 129             ctx->_TriangleCaps &= ~DD_POINT_ATTEN;
 130          break;
 131       case GL_POINT_SIZE_MIN_EXT:
 132          if (params[0] < 0.0F) {
 133             _mesa_error( ctx, GL_INVALID_VALUE,
 134                          "glPointParameterf[v]{EXT,ARB}(param)" );
 135             return;
 136          }
 137          if (ctx->Point.MinSize == params[0])
 138             return;
 139          FLUSH_VERTICES(ctx, _NEW_POINT);
 140          ctx->Point.MinSize = params[0];
 141          break;
 142       case GL_POINT_SIZE_MAX_EXT:
 143          if (params[0] < 0.0F) {
 144             _mesa_error( ctx, GL_INVALID_VALUE,
 145                          "glPointParameterf[v]{EXT,ARB}(param)" );
 146             return;
 147          }
 148          if (ctx->Point.MaxSize == params[0])
 149             return;
 150          FLUSH_VERTICES(ctx, _NEW_POINT);
 151          ctx->Point.MaxSize = params[0];
 152          break;
 153       case GL_POINT_FADE_THRESHOLD_SIZE_EXT:
 154          if (params[0] < 0.0F) {
 155             _mesa_error( ctx, GL_INVALID_VALUE,
 156                          "glPointParameterf[v]{EXT,ARB}(param)" );
 157             return;
 158          }
 159          if (ctx->Point.Threshold == params[0])
 160             return;
 161          FLUSH_VERTICES(ctx, _NEW_POINT);
 162          ctx->Point.Threshold = params[0];
 163          break;
 164       case GL_POINT_SPRITE_R_MODE_NV:
 165          /* This is one area where ARB_point_sprite and NV_point_sprite
 166           * differ.  In ARB_point_sprite the POINT_SPRITE_R_MODE is
 167           * always ZERO.  NV_point_sprite adds the S and R modes.
 168           */
 169          if (_mesa_is_desktop_gl(ctx) && ctx->Extensions.NV_point_sprite) {
 170             GLenum value = (GLenum) params[0];
 171             if (value != GL_ZERO && value != GL_S && value != GL_R) {
 172                _mesa_error(ctx, GL_INVALID_VALUE,
 173                            "glPointParameterf[v]{EXT,ARB}(param)");
 174                return;
 175             }
 176             if (ctx->Point.SpriteRMode == value)
 177                return;
 178             FLUSH_VERTICES(ctx, _NEW_POINT);
 179             ctx->Point.SpriteRMode = value;
 180          }
 181          else {
 182             _mesa_error(ctx, GL_INVALID_ENUM,
 183                         "glPointParameterf[v]{EXT,ARB}(pname)");
 184             return;
 185          }
 186          break;
 187       case GL_POINT_SPRITE_COORD_ORIGIN:
 188          /* GL_POINT_SPRITE_COORD_ORIGIN was added to point sprites when the
 189           * extension was merged into OpenGL 2.0.
 190           */
 191          if ((ctx->API == API_OPENGL_COMPAT && ctx->Version >= 20)
 192              || ctx->API == API_OPENGL_CORE) {
 193             GLenum value = (GLenum) params[0];
 194             if (value != GL_LOWER_LEFT && value != GL_UPPER_LEFT) {
 195                _mesa_error(ctx, GL_INVALID_VALUE,
 196                            "glPointParameterf[v]{EXT,ARB}(param)");
 197                return;
 198             }
 199             if (ctx->Point.SpriteOrigin == value)
 200                return;
 201             FLUSH_VERTICES(ctx, _NEW_POINT);
 202             ctx->Point.SpriteOrigin = value;
 203          }
 204          else {
 205             _mesa_error(ctx, GL_INVALID_ENUM,
 206                         "glPointParameterf[v]{EXT,ARB}(pname)");
 207             return;
 208          }
 209          break;
 210       default:
 211          _mesa_error( ctx, GL_INVALID_ENUM,
 212                       "glPointParameterf[v]{EXT,ARB}(pname)" );
 213          return;
 214    }
 215
 216    if (ctx->Driver.PointParameterfv)
 217       (*ctx->Driver.PointParameterfv)(ctx, pname, params);
 218 }
 219
 220
 221
 222 /**
 223  * Initialize the context point state.
 224  *
 225  * \param ctx GL context.
 226  *
 227  * Initializes __struct gl_contextRec::Point and point related constants in
 228  * __struct gl_contextRec::Const.
 229  */
 230 void
 231 _mesa_init_point(struct gl_context *ctx)
 232 {
 233    GLuint i;
 234
 235    ctx->Point.SmoothFlag = GL_FALSE;
 236    ctx->Point.Size = 1.0;
 237    ctx->Point.Params[0] = 1.0;
 238    ctx->Point.Params[1] = 0.0;
 239    ctx->Point.Params[2] = 0.0;
 240    ctx->Point._Attenuated = GL_FALSE;
 241    ctx->Point.MinSize = 0.0;
 242    ctx->Point.MaxSize
 243       = MAX2(ctx->Const.MaxPointSize, ctx->Const.MaxPointSizeAA);
 244    ctx->Point.Threshold = 1.0;
 245
 246    /* Page 403 (page 423 of the PDF) of the OpenGL 3.0 spec says:
 247     *
 248     *     "Non-sprite points (section 3.4) - Enable/Disable targets
 249     *     POINT_SMOOTH and POINT_SPRITE, and all associated state. Point
 250     *     rasterization is always performed as though POINT_SPRITE were
 251     *     enabled."
 252     *
 253     * In a core context, the state will default to true, and the setters and
 254     * getters are disabled.
 255     */
 256    ctx->Point.PointSprite = (ctx->API == API_OPENGL_CORE ||
 257                              ctx->API == API_OPENGLES2);
 258
 259    ctx->Point.SpriteRMode = GL_ZERO; /* GL_NV_point_sprite (only!) */
 260    ctx->Point.SpriteOrigin = GL_UPPER_LEFT; /* GL_ARB_point_sprite */
 261    for (i = 0; i < Elements(ctx->Point.CoordReplace); i++) {
 262       ctx->Point.CoordReplace[i] = GL_FALSE; /* GL_ARB/NV_point_sprite */
 263    }
 264 }