3 * Mesa 3-D graphics library
6 * Copyright (C) 1999-2002 Brian Paul All Rights Reserved.
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the "Software"),
10 * to deal in the Software without restriction, including without limitation
11 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12 * and/or sell copies of the Software, and to permit persons to whom the
13 * Software is furnished to do so, subject to the following conditions:
15 * The above copyright notice and this permission notice shall be included
16 * in all copies or substantial portions of the Software.
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
22 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 * Keith Whitwell <keith@tungstengraphics.com>
30 static void TAG(triangle
)(GLcontext
*ctx
, GLuint e0
, GLuint e1
, GLuint e2
)
32 struct vertex_buffer
*VB
= &TNL_CONTEXT(ctx
)->vb
;
33 SWvertex
*verts
= SWSETUP_CONTEXT(ctx
)->verts
;
37 GLenum mode
= GL_FILL
;
39 GLchan saved_color
[3][4];
40 GLchan saved_spec
[3][4];
41 GLuint saved_index
[3];
48 if (IND
& (SS_TWOSIDE_BIT
| SS_OFFSET_BIT
| SS_UNFILLED_BIT
))
50 GLfloat ex
= v
[0]->win
[0] - v
[2]->win
[0];
51 GLfloat ey
= v
[0]->win
[1] - v
[2]->win
[1];
52 GLfloat fx
= v
[1]->win
[0] - v
[2]->win
[0];
53 GLfloat fy
= v
[1]->win
[1] - v
[2]->win
[1];
54 GLfloat cc
= ex
*fy
- ey
*fx
;
56 if (IND
& (SS_TWOSIDE_BIT
| SS_UNFILLED_BIT
))
58 facing
= (cc
< 0.0) ^ ctx
->Polygon
._FrontBit
;
59 if (ctx
->Stencil
.TestTwoSide
)
60 ctx
->_Facing
= facing
; /* for 2-sided stencil test */
62 if (IND
& SS_UNFILLED_BIT
)
63 mode
= facing
? ctx
->Polygon
.BackMode
: ctx
->Polygon
.FrontMode
;
66 if (IND
& SS_TWOSIDE_BIT
) {
67 if (IND
& SS_RGBA_BIT
) {
68 GLfloat (*vbcolor
)[4] = VB
->ColorPtr
[1]->data
;
70 COPY_CHAN4(saved_color
[0], v
[0]->color
);
71 COPY_CHAN4(saved_color
[1], v
[1]->color
);
72 COPY_CHAN4(saved_color
[2], v
[2]->color
);
74 SS_COLOR(v
[0]->color
, vbcolor
[e0
]);
75 SS_COLOR(v
[1]->color
, vbcolor
[e1
]);
76 SS_COLOR(v
[2]->color
, vbcolor
[e2
]);
78 if (VB
->SecondaryColorPtr
[1]) {
79 GLfloat (*vbspec
)[4] = VB
->SecondaryColorPtr
[1]->data
;
81 COPY_CHAN4(saved_spec
[0], v
[0]->specular
);
82 COPY_CHAN4(saved_spec
[1], v
[1]->specular
);
83 COPY_CHAN4(saved_spec
[2], v
[2]->specular
);
85 SS_SPEC(v
[0]->specular
, vbspec
[e0
]);
86 SS_SPEC(v
[1]->specular
, vbspec
[e1
]);
87 SS_SPEC(v
[2]->specular
, vbspec
[e2
]);
90 GLfloat
*vbindex
= (GLfloat
*)VB
->IndexPtr
[1]->data
;
91 saved_index
[0] = v
[0]->index
;
92 saved_index
[1] = v
[1]->index
;
93 saved_index
[2] = v
[2]->index
;
95 SS_IND(v
[0]->index
, (GLuint
) vbindex
[e0
]);
96 SS_IND(v
[1]->index
, (GLuint
) vbindex
[e1
]);
97 SS_IND(v
[2]->index
, (GLuint
) vbindex
[e2
]);
103 if (IND
& SS_OFFSET_BIT
)
105 offset
= ctx
->Polygon
.OffsetUnits
;
109 if (cc
* cc
> 1e-16) {
110 GLfloat ez
= z
[0] - z
[2];
111 GLfloat fz
= z
[1] - z
[2];
112 GLfloat a
= ey
*fz
- ez
*fy
;
113 GLfloat b
= ez
*fx
- ex
*fz
;
114 GLfloat ic
= 1.0F
/ cc
;
117 if (ac
< 0.0F
) ac
= -ac
;
118 if (bc
< 0.0F
) bc
= -bc
;
119 offset
+= MAX2(ac
, bc
) * ctx
->Polygon
.OffsetFactor
;
122 /*printf("offset %g\n", offset);*/
126 if (mode
== GL_POINT
) {
127 if ((IND
& SS_OFFSET_BIT
) && ctx
->Polygon
.OffsetPoint
) {
128 v
[0]->win
[2] += offset
;
129 v
[1]->win
[2] += offset
;
130 v
[2]->win
[2] += offset
;
132 _swsetup_render_point_tri( ctx
, e0
, e1
, e2
, facing
);
133 } else if (mode
== GL_LINE
) {
134 if ((IND
& SS_OFFSET_BIT
) && ctx
->Polygon
.OffsetLine
) {
135 v
[0]->win
[2] += offset
;
136 v
[1]->win
[2] += offset
;
137 v
[2]->win
[2] += offset
;
139 _swsetup_render_line_tri( ctx
, e0
, e1
, e2
, facing
);
141 if ((IND
& SS_OFFSET_BIT
) && ctx
->Polygon
.OffsetFill
) {
142 v
[0]->win
[2] += offset
;
143 v
[1]->win
[2] += offset
;
144 v
[2]->win
[2] += offset
;
146 _swrast_Triangle( ctx
, v
[0], v
[1], v
[2] );
149 if (IND
& SS_OFFSET_BIT
) {
155 if (IND
& SS_TWOSIDE_BIT
) {
157 if (IND
& SS_RGBA_BIT
) {
158 COPY_CHAN4(v
[0]->color
, saved_color
[0]);
159 COPY_CHAN4(v
[1]->color
, saved_color
[1]);
160 COPY_CHAN4(v
[2]->color
, saved_color
[2]);
161 if (VB
->SecondaryColorPtr
[1]) {
162 COPY_CHAN4(v
[0]->specular
, saved_spec
[0]);
163 COPY_CHAN4(v
[1]->specular
, saved_spec
[1]);
164 COPY_CHAN4(v
[2]->specular
, saved_spec
[2]);
167 v
[0]->index
= saved_index
[0];
168 v
[1]->index
= saved_index
[1];
169 v
[2]->index
= saved_index
[2];
177 /* Need to fixup edgeflags when decomposing to triangles:
179 static void TAG(quadfunc
)( GLcontext
*ctx
, GLuint v0
,
180 GLuint v1
, GLuint v2
, GLuint v3
)
182 if (IND
& SS_UNFILLED_BIT
) {
183 struct vertex_buffer
*VB
= &TNL_CONTEXT(ctx
)->vb
;
184 GLubyte ef1
= VB
->EdgeFlag
[v1
];
185 GLubyte ef3
= VB
->EdgeFlag
[v3
];
186 VB
->EdgeFlag
[v1
] = 0;
187 TAG(triangle
)( ctx
, v0
, v1
, v3
);
188 VB
->EdgeFlag
[v1
] = ef1
;
189 VB
->EdgeFlag
[v3
] = 0;
190 TAG(triangle
)( ctx
, v1
, v2
, v3
);
191 VB
->EdgeFlag
[v3
] = ef3
;
193 TAG(triangle
)( ctx
, v0
, v1
, v3
);
194 TAG(triangle
)( ctx
, v1
, v2
, v3
);
201 static void TAG(init
)( void )
203 tri_tab
[IND
] = TAG(triangle
);
204 quad_tab
[IND
] = TAG(quadfunc
);