1 /**************************************************************************
3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 **************************************************************************/
29 * \brief Drawing stage for handling glPolygonMode(line/point).
30 * Convert triangles to points or lines as needed.
33 /* Authors: Keith Whitwell <keith@tungstengraphics.com>
36 #include "util/u_memory.h"
37 #include "pipe/p_defines.h"
38 #include "draw_private.h"
39 #include "draw_pipe.h"
43 struct unfilled_stage
{
44 struct draw_stage stage
;
46 /** [0] = front face, [1] = back face.
47 * legal values: PIPE_POLYGON_MODE_FILL, PIPE_POLYGON_MODE_LINE,
48 * and PIPE_POLYGON_MODE_POINT,
56 static INLINE
struct unfilled_stage
*unfilled_stage( struct draw_stage
*stage
)
58 return (struct unfilled_stage
*)stage
;
62 inject_front_face_info(struct draw_stage
*stage
,
63 struct prim_header
*header
)
65 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
66 unsigned ccw
= header
->det
< 0.0;
67 boolean is_front_face
= (
68 (stage
->draw
->rasterizer
->front_ccw
&& ccw
) ||
69 (!stage
->draw
->rasterizer
->front_ccw
&& !ccw
));
70 int slot
= unfilled
->face_slot
;
73 /* In case the backend doesn't care about it */
78 for (i
= 0; i
< 3; ++i
) {
79 struct vertex_header
*v
= header
->v
[i
];
80 v
->data
[slot
][0] = is_front_face
;
81 v
->data
[slot
][1] = is_front_face
;
82 v
->data
[slot
][2] = is_front_face
;
83 v
->data
[slot
][3] = is_front_face
;
88 static void point( struct draw_stage
*stage
,
89 struct vertex_header
*v0
)
91 struct prim_header tmp
;
93 stage
->next
->point( stage
->next
, &tmp
);
96 static void line( struct draw_stage
*stage
,
97 struct vertex_header
*v0
,
98 struct vertex_header
*v1
)
100 struct prim_header tmp
;
103 stage
->next
->line( stage
->next
, &tmp
);
107 static void points( struct draw_stage
*stage
,
108 struct prim_header
*header
)
110 struct vertex_header
*v0
= header
->v
[0];
111 struct vertex_header
*v1
= header
->v
[1];
112 struct vertex_header
*v2
= header
->v
[2];
114 inject_front_face_info(stage
, header
);
116 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_0
) && v0
->edgeflag
) point( stage
, v0
);
117 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_1
) && v1
->edgeflag
) point( stage
, v1
);
118 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_2
) && v2
->edgeflag
) point( stage
, v2
);
122 static void lines( struct draw_stage
*stage
,
123 struct prim_header
*header
)
125 struct vertex_header
*v0
= header
->v
[0];
126 struct vertex_header
*v1
= header
->v
[1];
127 struct vertex_header
*v2
= header
->v
[2];
129 if (header
->flags
& DRAW_PIPE_RESET_STIPPLE
)
130 stage
->next
->reset_stipple_counter( stage
->next
);
132 inject_front_face_info(stage
, header
);
134 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_2
) && v2
->edgeflag
) line( stage
, v2
, v0
);
135 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_0
) && v0
->edgeflag
) line( stage
, v0
, v1
);
136 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_1
) && v1
->edgeflag
) line( stage
, v1
, v2
);
142 print_header_flags(unsigned flags
)
144 debug_printf("header->flags = ");
145 if (flags
& DRAW_PIPE_RESET_STIPPLE
)
146 debug_printf("RESET_STIPPLE ");
147 if (flags
& DRAW_PIPE_EDGE_FLAG_0
)
148 debug_printf("EDGE_FLAG_0 ");
149 if (flags
& DRAW_PIPE_EDGE_FLAG_1
)
150 debug_printf("EDGE_FLAG_1 ");
151 if (flags
& DRAW_PIPE_EDGE_FLAG_2
)
152 debug_printf("EDGE_FLAG_2 ");
159 * Note edgeflags in the vertex struct is not sufficient as we will
160 * need to manipulate them when decomposing primitives.
162 * We currently keep the vertex edgeflag and primitive edgeflag mask
163 * separate until the last possible moment.
165 static void unfilled_tri( struct draw_stage
*stage
,
166 struct prim_header
*header
)
168 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
169 unsigned cw
= header
->det
>= 0.0;
170 unsigned mode
= unfilled
->mode
[cw
];
173 print_header_flags(header
->flags
);
176 case PIPE_POLYGON_MODE_FILL
:
177 stage
->next
->tri( stage
->next
, header
);
179 case PIPE_POLYGON_MODE_LINE
:
180 lines( stage
, header
);
182 case PIPE_POLYGON_MODE_POINT
:
183 points( stage
, header
);
191 static void unfilled_first_tri( struct draw_stage
*stage
,
192 struct prim_header
*header
)
194 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
195 const struct pipe_rasterizer_state
*rast
= stage
->draw
->rasterizer
;
197 unfilled
->mode
[0] = rast
->front_ccw
? rast
->fill_front
: rast
->fill_back
;
198 unfilled
->mode
[1] = rast
->front_ccw
? rast
->fill_back
: rast
->fill_front
;
200 stage
->tri
= unfilled_tri
;
201 stage
->tri( stage
, header
);
206 static void unfilled_flush( struct draw_stage
*stage
,
209 stage
->next
->flush( stage
->next
, flags
);
211 stage
->tri
= unfilled_first_tri
;
215 static void unfilled_reset_stipple_counter( struct draw_stage
*stage
)
217 stage
->next
->reset_stipple_counter( stage
->next
);
221 static void unfilled_destroy( struct draw_stage
*stage
)
223 draw_free_temp_verts( stage
);
228 * Try to allocate an output slot which we can use
229 * to preserve the front face information.
232 draw_unfilled_prepare_outputs( struct draw_context
*draw
,
233 struct draw_stage
*stage
)
235 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
236 const struct pipe_rasterizer_state
*rast
= draw
? draw
->rasterizer
: 0;
237 boolean is_unfilled
= (rast
&&
238 (rast
->fill_front
!= PIPE_POLYGON_MODE_FILL
||
239 rast
->fill_back
!= PIPE_POLYGON_MODE_FILL
));
240 const struct draw_fragment_shader
*fs
= draw
? draw
->fs
.fragment_shader
: 0;
242 if (is_unfilled
&& fs
&& fs
->info
.uses_frontface
) {
243 unfilled
->face_slot
= draw_alloc_extra_vertex_attrib(
244 stage
->draw
, TGSI_SEMANTIC_FACE
, 0);
246 unfilled
->face_slot
= -1;
252 * Create unfilled triangle stage.
254 struct draw_stage
*draw_unfilled_stage( struct draw_context
*draw
)
256 struct unfilled_stage
*unfilled
= CALLOC_STRUCT(unfilled_stage
);
257 if (unfilled
== NULL
)
260 unfilled
->stage
.draw
= draw
;
261 unfilled
->stage
.name
= "unfilled";
262 unfilled
->stage
.next
= NULL
;
263 unfilled
->stage
.tmp
= NULL
;
264 unfilled
->stage
.point
= draw_pipe_passthrough_point
;
265 unfilled
->stage
.line
= draw_pipe_passthrough_line
;
266 unfilled
->stage
.tri
= unfilled_first_tri
;
267 unfilled
->stage
.flush
= unfilled_flush
;
268 unfilled
->stage
.reset_stipple_counter
= unfilled_reset_stipple_counter
;
269 unfilled
->stage
.destroy
= unfilled_destroy
;
271 unfilled
->face_slot
= -1;
273 if (!draw_alloc_temp_verts( &unfilled
->stage
, 0 ))
276 return &unfilled
->stage
;
280 unfilled
->stage
.destroy( &unfilled
->stage
);