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    ASSERT_OUTSIDE_BEGIN_END(ctx);
  48
  49    if (size <= 0.0) {
  50       _mesa_error( ctx, GL_INVALID_VALUE, "glPointSize" );
  51       return;
  52    }
  53
  54    if (ctx->Point.Size == size)
  55       return;
  56
  57    FLUSH_VERTICES(ctx, _NEW_POINT);
  58    ctx->Point.Size = size;
  59
  60    if (ctx->Driver.PointSize)
  61       ctx->Driver.PointSize(ctx, size);
  62 }
  63
  64
  65 void GLAPIENTRY
  66 _mesa_PointParameteri( GLenum pname, GLint param )
  67 {
  68    GLfloat p[3];
  69    p[0] = (GLfloat) param;
  70    p[1] = p[2] = 0.0F;
  71    _mesa_PointParameterfv(pname, p);
  72 }
  73
  74
  75 void GLAPIENTRY
  76 _mesa_PointParameteriv( GLenum pname, const GLint *params )
  77 {
  78    GLfloat p[3];
  79    p[0] = (GLfloat) params[0];
  80    if (pname == GL_DISTANCE_ATTENUATION_EXT) {
  81       p[1] = (GLfloat) params[1];
  82       p[2] = (GLfloat) params[2];
  83    }
  84    _mesa_PointParameterfv(pname, p);
  85 }
  86
  87
  88 void GLAPIENTRY
  89 _mesa_PointParameterf( GLenum pname, GLfloat param)
  90 {
  91    GLfloat p[3];
  92    p[0] = param;
  93    p[1] = p[2] = 0.0F;
  94    _mesa_PointParameterfv(pname, p);
  95 }
  96
  97
  98 void GLAPIENTRY
  99 _mesa_PointParameterfv( GLenum pname, const GLfloat *params)
 100 {
 101    GET_CURRENT_CONTEXT(ctx);
 102    ASSERT_OUTSIDE_BEGIN_END(ctx);
 103
 104    /* Drivers that support point sprites must also support point parameters.
 105     * If point parameters aren't supported, then this function shouldn't even
 106     * exist.
 107     */
 108    ASSERT(!(ctx->Extensions.ARB_point_sprite
 109             || ctx->Extensions.NV_point_sprite)
 110           || ctx->Extensions.EXT_point_parameters);
 111
 112    if (!ctx->Extensions.EXT_point_parameters) {
 113       _mesa_error(ctx, GL_INVALID_OPERATION,
 114                   "unsupported function called (unsupported extension)");
 115       return;
 116    }
 117
 118    switch (pname) {
 119       case GL_DISTANCE_ATTENUATION_EXT:
 120          if (TEST_EQ_3V(ctx->Point.Params, params))
 121             return;
 122          FLUSH_VERTICES(ctx, _NEW_POINT);
 123          COPY_3V(ctx->Point.Params, params);
 124          ctx->Point._Attenuated = (ctx->Point.Params[0] != 1.0 ||
 125                                    ctx->Point.Params[1] != 0.0 ||
 126                                    ctx->Point.Params[2] != 0.0);
 127
 128          if (ctx->Point._Attenuated)
 129             ctx->_TriangleCaps |= DD_POINT_ATTEN;
 130          else
 131             ctx->_TriangleCaps &= ~DD_POINT_ATTEN;
 132          break;
 133       case GL_POINT_SIZE_MIN_EXT:
 134          if (params[0] < 0.0F) {
 135             _mesa_error( ctx, GL_INVALID_VALUE,
 136                          "glPointParameterf[v]{EXT,ARB}(param)" );
 137             return;
 138          }
 139          if (ctx->Point.MinSize == params[0])
 140             return;
 141          FLUSH_VERTICES(ctx, _NEW_POINT);
 142          ctx->Point.MinSize = params[0];
 143          break;
 144       case GL_POINT_SIZE_MAX_EXT:
 145          if (params[0] < 0.0F) {
 146             _mesa_error( ctx, GL_INVALID_VALUE,
 147                          "glPointParameterf[v]{EXT,ARB}(param)" );
 148             return;
 149          }
 150          if (ctx->Point.MaxSize == params[0])
 151             return;
 152          FLUSH_VERTICES(ctx, _NEW_POINT);
 153          ctx->Point.MaxSize = params[0];
 154          break;
 155       case GL_POINT_FADE_THRESHOLD_SIZE_EXT:
 156          if (params[0] < 0.0F) {
 157             _mesa_error( ctx, GL_INVALID_VALUE,
 158                          "glPointParameterf[v]{EXT,ARB}(param)" );
 159             return;
 160          }
 161          if (ctx->Point.Threshold == params[0])
 162             return;
 163          FLUSH_VERTICES(ctx, _NEW_POINT);
 164          ctx->Point.Threshold = params[0];
 165          break;
 166       case GL_POINT_SPRITE_R_MODE_NV:
 167          /* This is one area where ARB_point_sprite and NV_point_sprite
 168           * differ.  In ARB_point_sprite the POINT_SPRITE_R_MODE is
 169           * always ZERO.  NV_point_sprite adds the S and R modes.
 170           */
 171          if (_mesa_is_desktop_gl(ctx) && ctx->Extensions.NV_point_sprite) {
 172             GLenum value = (GLenum) params[0];
 173             if (value != GL_ZERO && value != GL_S && value != GL_R) {
 174                _mesa_error(ctx, GL_INVALID_VALUE,
 175                            "glPointParameterf[v]{EXT,ARB}(param)");
 176                return;
 177             }
 178             if (ctx->Point.SpriteRMode == value)
 179                return;
 180             FLUSH_VERTICES(ctx, _NEW_POINT);
 181             ctx->Point.SpriteRMode = value;
 182          }
 183          else {
 184             _mesa_error(ctx, GL_INVALID_ENUM,
 185                         "glPointParameterf[v]{EXT,ARB}(pname)");
 186             return;
 187          }
 188          break;
 189       case GL_POINT_SPRITE_COORD_ORIGIN:
 190          /* GL_POINT_SPRITE_COORD_ORIGIN was added to point sprites when the
 191           * extension was merged into OpenGL 2.0.
 192           */
 193          if ((ctx->API == API_OPENGL_COMPAT && ctx->Version >= 20)
 194              || ctx->API == API_OPENGL_CORE) {
 195             GLenum value = (GLenum) params[0];
 196             if (value != GL_LOWER_LEFT && value != GL_UPPER_LEFT) {
 197                _mesa_error(ctx, GL_INVALID_VALUE,
 198                            "glPointParameterf[v]{EXT,ARB}(param)");
 199                return;
 200             }
 201             if (ctx->Point.SpriteOrigin == value)
 202                return;
 203             FLUSH_VERTICES(ctx, _NEW_POINT);
 204             ctx->Point.SpriteOrigin = value;
 205          }
 206          else {
 207             _mesa_error(ctx, GL_INVALID_ENUM,
 208                         "glPointParameterf[v]{EXT,ARB}(pname)");
 209             return;
 210          }
 211          break;
 212       default:
 213          _mesa_error( ctx, GL_INVALID_ENUM,
 214                       "glPointParameterf[v]{EXT,ARB}(pname)" );
 215          return;
 216    }
 217
 218    if (ctx->Driver.PointParameterfv)
 219       (*ctx->Driver.PointParameterfv)(ctx, pname, params);
 220 }
 221
 222
 223
 224 /**
 225  * Initialize the context point state.
 226  *
 227  * \param ctx GL context.
 228  *
 229  * Initializes __struct gl_contextRec::Point and point related constants in
 230  * __struct gl_contextRec::Const.
 231  */
 232 void
 233 _mesa_init_point(struct gl_context *ctx)
 234 {
 235    GLuint i;
 236
 237    ctx->Point.SmoothFlag = GL_FALSE;
 238    ctx->Point.Size = 1.0;
 239    ctx->Point.Params[0] = 1.0;
 240    ctx->Point.Params[1] = 0.0;
 241    ctx->Point.Params[2] = 0.0;
 242    ctx->Point._Attenuated = GL_FALSE;
 243    ctx->Point.MinSize = 0.0;
 244    ctx->Point.MaxSize
 245       = MAX2(ctx->Const.MaxPointSize, ctx->Const.MaxPointSizeAA);
 246    ctx->Point.Threshold = 1.0;
 247
 248    /* Page 403 (page 423 of the PDF) of the OpenGL 3.0 spec says:
 249     *
 250     *     "Non-sprite points (section 3.4) - Enable/Disable targets
 251     *     POINT_SMOOTH and POINT_SPRITE, and all associated state. Point
 252     *     rasterization is always performed as though POINT_SPRITE were
 253     *     enabled."
 254     *
 255     * In a core context, the state will default to true, and the setters and
 256     * getters are disabled.
 257     */
 258    ctx->Point.PointSprite = (ctx->API == API_OPENGL_CORE);
 259
 260    ctx->Point.SpriteRMode = GL_ZERO; /* GL_NV_point_sprite (only!) */
 261    ctx->Point.SpriteOrigin = GL_UPPER_LEFT; /* GL_ARB_point_sprite */
 262    for (i = 0; i < Elements(ctx->Point.CoordReplace); i++) {
 263       ctx->Point.CoordReplace[i] = GL_FALSE; /* GL_ARB/NV_point_sprite */
 264    }
 265 }