lines.c revision 3d8d5b298a268b119d840bc9bae0ee9e0c9244a9 
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.5.3
4 *
5 * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27#include "glheader.h"
28#include "context.h"
29#include "lines.h"
30#include "macros.h"
31#include "mtypes.h"
32
33
34/**
35 * Set the line width.
36 *
37 * \param width line width in pixels.
38 *
39 * \sa glLineWidth().
40 */
41void GLAPIENTRY
42_mesa_LineWidth( GLfloat width )
43{
44   GET_CURRENT_CONTEXT(ctx);
45
46   if (MESA_VERBOSE & VERBOSE_API)
47      _mesa_debug(ctx, "glLineWidth %f\n", width);
48
49   if (width<=0.0) {
50      _mesa_error( ctx, GL_INVALID_VALUE, "glLineWidth" );
51      return;
52   }
53
54   /* Page 407 (page 423 of the PDF) of the OpenGL 3.0 spec says (in the list
55    * of deprecated functionality):
56    *
57    *     "Wide lines and line stipple - LineWidth is not deprecated, but
58    *     values greater than 1.0 will generate an INVALID_VALUE error;"
59    *
60    * This is one of the very few cases where functionality was deprecated but
61    * *NOT* removed in a later spec.  Therefore, we only disallow this in a
62    * forward compatible context.
63    */
64   if (ctx->API == API_OPENGL_CORE
65       && ((ctx->Const.ContextFlags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT)
66           != 0)) {
67      _mesa_error( ctx, GL_INVALID_VALUE, "glLineWidth" );
68      return;
69   }
70
71   if (ctx->Line.Width == width)
72      return;
73
74   FLUSH_VERTICES(ctx, _NEW_LINE);
75   ctx->Line.Width = width;
76
77   if (ctx->Driver.LineWidth)
78      ctx->Driver.LineWidth(ctx, width);
79}
80
81
82/**
83 * Set the line stipple pattern.
84 *
85 * \param factor pattern scale factor.
86 * \param pattern bit pattern.
87 *
88 * \sa glLineStipple().
89 *
90 * Updates gl_line_attrib::StippleFactor and gl_line_attrib::StipplePattern. On
91 * change flushes the vertices and notifies the driver via
92 * the dd_function_table::LineStipple callback.
93 */
94void GLAPIENTRY
95_mesa_LineStipple( GLint factor, GLushort pattern )
96{
97   GET_CURRENT_CONTEXT(ctx);
98
99   if (MESA_VERBOSE & VERBOSE_API)
100      _mesa_debug(ctx, "glLineStipple %d %u\n", factor, pattern);
101
102   factor = CLAMP( factor, 1, 256 );
103
104   if (ctx->Line.StippleFactor == factor &&
105       ctx->Line.StipplePattern == pattern)
106      return;
107
108   FLUSH_VERTICES(ctx, _NEW_LINE);
109   ctx->Line.StippleFactor = factor;
110   ctx->Line.StipplePattern = pattern;
111
112   if (ctx->Driver.LineStipple)
113      ctx->Driver.LineStipple( ctx, factor, pattern );
114}
115
116
117/**
118 * Initialize the context line state.
119 *
120 * \param ctx GL context.
121 *
122 * Initializes __struct gl_contextRec::Line and line related constants in
123 * __struct gl_contextRec::Const.
124 */
125void GLAPIENTRY
126_mesa_init_line( struct gl_context * ctx )
127{
128   ctx->Line.SmoothFlag = GL_FALSE;
129   ctx->Line.StippleFlag = GL_FALSE;
130   ctx->Line.Width = 1.0;
131   ctx->Line.StipplePattern = 0xffff;
132   ctx->Line.StippleFactor = 1;
133}
134