1 /*
2  * Mesa 3-D graphics library
3  *
4  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included
14  * in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  */
24 
25 
26 #include "glheader.h"
27 #include "context.h"
28 #include "lines.h"
29 #include "macros.h"
30 #include "mtypes.h"
31 
32 
33 /**
34  * Set the line width.
35  *
36  * \param width line width in pixels.
37  *
38  * \sa glLineWidth().
39  */
40 static ALWAYS_INLINE void
line_width(struct gl_context * ctx,GLfloat width,bool no_error)41 line_width(struct gl_context *ctx, GLfloat width, bool no_error)
42 {
43    /* If width is unchanged, there can't be an error */
44    if (ctx->Line.Width == width)
45       return;
46 
47    if (!no_error && width <= 0.0F) {
48       _mesa_error( ctx, GL_INVALID_VALUE, "glLineWidth" );
49       return;
50    }
51 
52    /* Page 407 (page 423 of the PDF) of the OpenGL 3.0 spec says (in the list
53     * of deprecated functionality):
54     *
55     *     "Wide lines and line stipple - LineWidth is not deprecated, but
56     *     values greater than 1.0 will generate an INVALID_VALUE error;"
57     *
58     * This is one of the very few cases where functionality was deprecated but
59     * *NOT* removed in a later spec.  Therefore, we only disallow this in a
60     * forward compatible context.
61     */
62    if (!no_error && ctx->API == API_OPENGL_CORE
63        && ((ctx->Const.ContextFlags & GL_CONTEXT_FLAG_FORWARD_COMPATIBLE_BIT)
64            != 0)
65        && width > 1.0F) {
66       _mesa_error( ctx, GL_INVALID_VALUE, "glLineWidth" );
67       return;
68    }
69 
70    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewLineState ? 0 : _NEW_LINE);
71    ctx->NewDriverState |= ctx->DriverFlags.NewLineState;
72    ctx->Line.Width = width;
73 
74    if (ctx->Driver.LineWidth)
75       ctx->Driver.LineWidth(ctx, width);
76 }
77 
78 
79 void GLAPIENTRY
_mesa_LineWidth_no_error(GLfloat width)80 _mesa_LineWidth_no_error(GLfloat width)
81 {
82    GET_CURRENT_CONTEXT(ctx);
83    line_width(ctx, width, true);
84 }
85 
86 
87 void GLAPIENTRY
_mesa_LineWidth(GLfloat width)88 _mesa_LineWidth(GLfloat width)
89 {
90    GET_CURRENT_CONTEXT(ctx);
91 
92    if (MESA_VERBOSE & VERBOSE_API)
93       _mesa_debug(ctx, "glLineWidth %f\n", width);
94 
95    line_width(ctx, width, false);
96 }
97 
98 
99 /**
100  * Set the line stipple pattern.
101  *
102  * \param factor pattern scale factor.
103  * \param pattern bit pattern.
104  *
105  * \sa glLineStipple().
106  *
107  * Updates gl_line_attrib::StippleFactor and gl_line_attrib::StipplePattern. On
108  * change flushes the vertices and notifies the driver via
109  * the dd_function_table::LineStipple callback.
110  */
111 void GLAPIENTRY
_mesa_LineStipple(GLint factor,GLushort pattern)112 _mesa_LineStipple( GLint factor, GLushort pattern )
113 {
114    GET_CURRENT_CONTEXT(ctx);
115 
116    if (MESA_VERBOSE & VERBOSE_API)
117       _mesa_debug(ctx, "glLineStipple %d %u\n", factor, pattern);
118 
119    factor = CLAMP( factor, 1, 256 );
120 
121    if (ctx->Line.StippleFactor == factor &&
122        ctx->Line.StipplePattern == pattern)
123       return;
124 
125    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewLineState ? 0 : _NEW_LINE);
126    ctx->NewDriverState |= ctx->DriverFlags.NewLineState;
127    ctx->Line.StippleFactor = factor;
128    ctx->Line.StipplePattern = pattern;
129 
130    if (ctx->Driver.LineStipple)
131       ctx->Driver.LineStipple( ctx, factor, pattern );
132 }
133 
134 
135 /**
136  * Initialize the context line state.
137  *
138  * \param ctx GL context.
139  *
140  * Initializes __struct gl_contextRec::Line and line related constants in
141  * __struct gl_contextRec::Const.
142  */
143 void
_mesa_init_line(struct gl_context * ctx)144 _mesa_init_line( struct gl_context * ctx )
145 {
146    ctx->Line.SmoothFlag = GL_FALSE;
147    ctx->Line.StippleFlag = GL_FALSE;
148    ctx->Line.Width = 1.0;
149    ctx->Line.StipplePattern = 0xffff;
150    ctx->Line.StippleFactor = 1;
151 }
152