1 /**************************************************************************
3 * Copyright 2007 VMware, Inc.
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 VMWARE 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 <keithw@vmware.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
;
84 v
->vertex_id
= UNDEFINED_VERTEX_ID
;
89 static void point( struct draw_stage
*stage
,
90 struct vertex_header
*v0
)
92 struct prim_header tmp
;
94 stage
->next
->point( stage
->next
, &tmp
);
97 static void line( struct draw_stage
*stage
,
98 struct vertex_header
*v0
,
99 struct vertex_header
*v1
)
101 struct prim_header tmp
;
104 stage
->next
->line( stage
->next
, &tmp
);
108 static void points( struct draw_stage
*stage
,
109 struct prim_header
*header
)
111 struct vertex_header
*v0
= header
->v
[0];
112 struct vertex_header
*v1
= header
->v
[1];
113 struct vertex_header
*v2
= header
->v
[2];
115 inject_front_face_info(stage
, header
);
117 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_0
) && v0
->edgeflag
) point( stage
, v0
);
118 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_1
) && v1
->edgeflag
) point( stage
, v1
);
119 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_2
) && v2
->edgeflag
) point( stage
, v2
);
123 static void lines( struct draw_stage
*stage
,
124 struct prim_header
*header
)
126 struct vertex_header
*v0
= header
->v
[0];
127 struct vertex_header
*v1
= header
->v
[1];
128 struct vertex_header
*v2
= header
->v
[2];
130 if (header
->flags
& DRAW_PIPE_RESET_STIPPLE
)
131 stage
->next
->reset_stipple_counter( stage
->next
);
133 inject_front_face_info(stage
, header
);
135 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_2
) && v2
->edgeflag
) line( stage
, v2
, v0
);
136 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_0
) && v0
->edgeflag
) line( stage
, v0
, v1
);
137 if ((header
->flags
& DRAW_PIPE_EDGE_FLAG_1
) && v1
->edgeflag
) line( stage
, v1
, v2
);
143 print_header_flags(unsigned flags
)
145 debug_printf("header->flags = ");
146 if (flags
& DRAW_PIPE_RESET_STIPPLE
)
147 debug_printf("RESET_STIPPLE ");
148 if (flags
& DRAW_PIPE_EDGE_FLAG_0
)
149 debug_printf("EDGE_FLAG_0 ");
150 if (flags
& DRAW_PIPE_EDGE_FLAG_1
)
151 debug_printf("EDGE_FLAG_1 ");
152 if (flags
& DRAW_PIPE_EDGE_FLAG_2
)
153 debug_printf("EDGE_FLAG_2 ");
160 * Note edgeflags in the vertex struct is not sufficient as we will
161 * need to manipulate them when decomposing primitives.
163 * We currently keep the vertex edgeflag and primitive edgeflag mask
164 * separate until the last possible moment.
166 static void unfilled_tri( struct draw_stage
*stage
,
167 struct prim_header
*header
)
169 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
170 unsigned cw
= header
->det
>= 0.0;
171 unsigned mode
= unfilled
->mode
[cw
];
174 print_header_flags(header
->flags
);
177 case PIPE_POLYGON_MODE_FILL
:
178 stage
->next
->tri( stage
->next
, header
);
180 case PIPE_POLYGON_MODE_LINE
:
181 lines( stage
, header
);
183 case PIPE_POLYGON_MODE_POINT
:
184 points( stage
, header
);
192 static void unfilled_first_tri( struct draw_stage
*stage
,
193 struct prim_header
*header
)
195 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
196 const struct pipe_rasterizer_state
*rast
= stage
->draw
->rasterizer
;
198 unfilled
->mode
[0] = rast
->front_ccw
? rast
->fill_front
: rast
->fill_back
;
199 unfilled
->mode
[1] = rast
->front_ccw
? rast
->fill_back
: rast
->fill_front
;
201 stage
->tri
= unfilled_tri
;
202 stage
->tri( stage
, header
);
207 static void unfilled_flush( struct draw_stage
*stage
,
210 stage
->next
->flush( stage
->next
, flags
);
212 stage
->tri
= unfilled_first_tri
;
216 static void unfilled_reset_stipple_counter( struct draw_stage
*stage
)
218 stage
->next
->reset_stipple_counter( stage
->next
);
222 static void unfilled_destroy( struct draw_stage
*stage
)
224 draw_free_temp_verts( stage
);
229 * Try to allocate an output slot which we can use
230 * to preserve the front face information.
233 draw_unfilled_prepare_outputs( struct draw_context
*draw
,
234 struct draw_stage
*stage
)
236 struct unfilled_stage
*unfilled
= unfilled_stage(stage
);
237 const struct pipe_rasterizer_state
*rast
= draw
? draw
->rasterizer
: 0;
238 boolean is_unfilled
= (rast
&&
239 (rast
->fill_front
!= PIPE_POLYGON_MODE_FILL
||
240 rast
->fill_back
!= PIPE_POLYGON_MODE_FILL
));
241 const struct draw_fragment_shader
*fs
= draw
? draw
->fs
.fragment_shader
: 0;
243 if (is_unfilled
&& fs
&& fs
->info
.uses_frontface
) {
244 unfilled
->face_slot
= draw_alloc_extra_vertex_attrib(
245 stage
->draw
, TGSI_SEMANTIC_FACE
, 0);
247 unfilled
->face_slot
= -1;
253 * Create unfilled triangle stage.
255 struct draw_stage
*draw_unfilled_stage( struct draw_context
*draw
)
257 struct unfilled_stage
*unfilled
= CALLOC_STRUCT(unfilled_stage
);
261 unfilled
->stage
.draw
= draw
;
262 unfilled
->stage
.name
= "unfilled";
263 unfilled
->stage
.next
= NULL
;
264 unfilled
->stage
.tmp
= NULL
;
265 unfilled
->stage
.point
= draw_pipe_passthrough_point
;
266 unfilled
->stage
.line
= draw_pipe_passthrough_line
;
267 unfilled
->stage
.tri
= unfilled_first_tri
;
268 unfilled
->stage
.flush
= unfilled_flush
;
269 unfilled
->stage
.reset_stipple_counter
= unfilled_reset_stipple_counter
;
270 unfilled
->stage
.destroy
= unfilled_destroy
;
272 unfilled
->face_slot
= -1;
274 if (!draw_alloc_temp_verts( &unfilled
->stage
, 0 ))
277 return &unfilled
->stage
;
281 unfilled
->stage
.destroy( &unfilled
->stage
);