points.c revision 7ec681f3 
1/**
2 * \file points.c
3 * Point operations.
4 */
5
6/*
7 * Mesa 3-D graphics library
8 *
9 * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
10 *
11 * Permission is hereby granted, free of charge, to any person obtaining a
12 * copy of this software and associated documentation files (the "Software"),
13 * to deal in the Software without restriction, including without limitation
14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15 * and/or sell copies of the Software, and to permit persons to whom the
16 * Software is furnished to do so, subject to the following conditions:
17 *
18 * The above copyright notice and this permission notice shall be included
19 * in all copies or substantial portions of the Software.
20 *
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
22 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
24 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
25 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
26 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
27 * 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 */
43static ALWAYS_INLINE void
44point_size(struct gl_context *ctx, GLfloat size, bool no_error)
45{
46   if (ctx->Point.Size == size)
47      return;
48
49   if (!no_error && size <= 0.0F) {
50      _mesa_error(ctx, GL_INVALID_VALUE, "glPointSize");
51      return;
52   }
53
54   FLUSH_VERTICES(ctx, _NEW_POINT, GL_POINT_BIT);
55   ctx->Point.Size = size;
56
57   if (ctx->Driver.PointSize)
58      ctx->Driver.PointSize(ctx, size);
59}
60
61
62void GLAPIENTRY
63_mesa_PointSize_no_error(GLfloat size)
64{
65   GET_CURRENT_CONTEXT(ctx);
66   point_size(ctx, size, true);
67}
68
69
70void GLAPIENTRY
71_mesa_PointSize( GLfloat size )
72{
73   GET_CURRENT_CONTEXT(ctx);
74   point_size(ctx, size, false);
75}
76
77
78void GLAPIENTRY
79_mesa_PointParameteri( GLenum pname, GLint param )
80{
81   GLfloat p[3];
82   p[0] = (GLfloat) param;
83   p[1] = p[2] = 0.0F;
84   _mesa_PointParameterfv(pname, p);
85}
86
87
88void GLAPIENTRY
89_mesa_PointParameteriv( GLenum pname, const GLint *params )
90{
91   GLfloat p[3];
92   p[0] = (GLfloat) params[0];
93   if (pname == GL_DISTANCE_ATTENUATION_EXT) {
94      p[1] = (GLfloat) params[1];
95      p[2] = (GLfloat) params[2];
96   }
97   _mesa_PointParameterfv(pname, p);
98}
99
100
101void GLAPIENTRY
102_mesa_PointParameterf( GLenum pname, GLfloat param)
103{
104   GLfloat p[3];
105   p[0] = param;
106   p[1] = p[2] = 0.0F;
107   _mesa_PointParameterfv(pname, p);
108}
109
110
111void GLAPIENTRY
112_mesa_PointParameterfv( GLenum pname, const GLfloat *params)
113{
114   GET_CURRENT_CONTEXT(ctx);
115
116   /* Drivers that support point sprites must also support point parameters.
117    * If point parameters aren't supported, then this function shouldn't even
118    * exist.
119    */
120   assert(!ctx->Extensions.ARB_point_sprite ||
121          ctx->Extensions.EXT_point_parameters);
122
123   if (!ctx->Extensions.EXT_point_parameters) {
124      _mesa_error(ctx, GL_INVALID_OPERATION,
125                  "unsupported function called (unsupported extension)");
126      return;
127   }
128
129   switch (pname) {
130      case GL_DISTANCE_ATTENUATION_EXT:
131         if (TEST_EQ_3V(ctx->Point.Params, params))
132            return;
133         FLUSH_VERTICES(ctx, _NEW_POINT | _NEW_FF_VERT_PROGRAM |
134                        _NEW_TNL_SPACES, GL_POINT_BIT);
135         COPY_3V(ctx->Point.Params, params);
136         ctx->Point._Attenuated = (ctx->Point.Params[0] != 1.0F ||
137                                   ctx->Point.Params[1] != 0.0F ||
138                                   ctx->Point.Params[2] != 0.0F);
139         break;
140      case GL_POINT_SIZE_MIN_EXT:
141         if (params[0] < 0.0F) {
142            _mesa_error( ctx, GL_INVALID_VALUE,
143                         "glPointParameterf[v]{EXT,ARB}(param)" );
144            return;
145         }
146         if (ctx->Point.MinSize == params[0])
147            return;
148         FLUSH_VERTICES(ctx, _NEW_POINT, GL_POINT_BIT);
149         ctx->Point.MinSize = params[0];
150         break;
151      case GL_POINT_SIZE_MAX_EXT:
152         if (params[0] < 0.0F) {
153            _mesa_error( ctx, GL_INVALID_VALUE,
154                         "glPointParameterf[v]{EXT,ARB}(param)" );
155            return;
156         }
157         if (ctx->Point.MaxSize == params[0])
158            return;
159         FLUSH_VERTICES(ctx, _NEW_POINT, GL_POINT_BIT);
160         ctx->Point.MaxSize = params[0];
161         break;
162      case GL_POINT_FADE_THRESHOLD_SIZE_EXT:
163         if (params[0] < 0.0F) {
164            _mesa_error( ctx, GL_INVALID_VALUE,
165                         "glPointParameterf[v]{EXT,ARB}(param)" );
166            return;
167         }
168         if (ctx->Point.Threshold == params[0])
169            return;
170         FLUSH_VERTICES(ctx, _NEW_POINT, GL_POINT_BIT);
171         ctx->Point.Threshold = params[0];
172         break;
173      case GL_POINT_SPRITE_COORD_ORIGIN:
174	 /* GL_POINT_SPRITE_COORD_ORIGIN was added to point sprites when the
175	  * extension was merged into OpenGL 2.0.
176	  */
177         if ((ctx->API == API_OPENGL_COMPAT && ctx->Version >= 20)
178             || ctx->API == API_OPENGL_CORE) {
179            GLenum value = (GLenum) params[0];
180            if (value != GL_LOWER_LEFT && value != GL_UPPER_LEFT) {
181               _mesa_error(ctx, GL_INVALID_VALUE,
182                           "glPointParameterf[v]{EXT,ARB}(param)");
183               return;
184            }
185            if (ctx->Point.SpriteOrigin == value)
186               return;
187            FLUSH_VERTICES(ctx, _NEW_POINT, GL_POINT_BIT);
188            ctx->Point.SpriteOrigin = value;
189         }
190         else {
191            _mesa_error(ctx, GL_INVALID_ENUM,
192                        "glPointParameterf[v]{EXT,ARB}(pname)");
193            return;
194         }
195         break;
196      default:
197         _mesa_error( ctx, GL_INVALID_ENUM,
198                      "glPointParameterf[v]{EXT,ARB}(pname)" );
199         return;
200   }
201
202   if (ctx->Driver.PointParameterfv)
203      ctx->Driver.PointParameterfv(ctx, pname, params);
204}
205
206
207
208/**
209 * Initialize the context point state.
210 *
211 * \param ctx GL context.
212 *
213 * Initializes __struct gl_contextRec::Point and point related constants in
214 * __struct gl_contextRec::Const.
215 */
216void
217_mesa_init_point(struct gl_context *ctx)
218{
219   ctx->Point.SmoothFlag = GL_FALSE;
220   ctx->Point.Size = 1.0;
221   ctx->Point.Params[0] = 1.0;
222   ctx->Point.Params[1] = 0.0;
223   ctx->Point.Params[2] = 0.0;
224   ctx->Point._Attenuated = GL_FALSE;
225   ctx->Point.MinSize = 0.0;
226   ctx->Point.MaxSize
227      = MAX2(ctx->Const.MaxPointSize, ctx->Const.MaxPointSizeAA);
228   ctx->Point.Threshold = 1.0;
229
230   /* Page 403 (page 423 of the PDF) of the OpenGL 3.0 spec says:
231    *
232    *     "Non-sprite points (section 3.4) - Enable/Disable targets
233    *     POINT_SMOOTH and POINT_SPRITE, and all associated state. Point
234    *     rasterization is always performed as though POINT_SPRITE were
235    *     enabled."
236    *
237    * In a core context, the state will default to true, and the setters and
238    * getters are disabled.
239    */
240   ctx->Point.PointSprite = (ctx->API == API_OPENGL_CORE ||
241                             ctx->API == API_OPENGLES2);
242
243   ctx->Point.SpriteOrigin = GL_UPPER_LEFT; /* GL_ARB_point_sprite */
244   ctx->Point.CoordReplace = 0; /* GL_ARB_point_sprite */
245}
246