summaryrefslogtreecommitdiffstats
path: root/src/gallium/auxiliary/draw/draw_flatshade.c
blob: ccad71d695797b87e3b39482f9a21cc16cd57848 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
/**************************************************************************
 * 
 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 **************************************************************************/

/* Authors:  Keith Whitwell <keith@tungstengraphics.com>
 */

#include "pipe/p_util.h"
#include "pipe/p_shader_tokens.h"
#include "draw_private.h"


/** subclass of draw_stage */
struct flat_stage
{
   struct draw_stage stage;

   uint num_color_attribs;
   uint color_attribs[4];  /* front/back primary/secondary colors */
};


static INLINE struct flat_stage *
flat_stage(struct draw_stage *stage)
{
   return (struct flat_stage *) stage;
}


/** Copy all the color attributes from 'src' vertex to 'dst' vertex */
static INLINE void copy_colors( struct draw_stage *stage,
                                struct vertex_header *dst,
                                const struct vertex_header *src )
{
   const struct flat_stage *flat = flat_stage(stage);
   uint i;
   for (i = 0; i < flat->num_color_attribs; i++) {
      const uint attr = flat->color_attribs[i];
      COPY_4FV(dst->data[attr], src->data[attr]);
   }
}


/** Copy all the color attributes from src vertex to dst0 & dst1 vertices */
static INLINE void copy_colors2( struct draw_stage *stage,
                                 struct vertex_header *dst0,
                                 struct vertex_header *dst1,
                                 const struct vertex_header *src )
{
   const struct flat_stage *flat = flat_stage(stage);
   uint i;
   for (i = 0; i < flat->num_color_attribs; i++) {
      const uint attr = flat->color_attribs[i];
      COPY_4FV(dst0->data[attr], src->data[attr]);
      COPY_4FV(dst1->data[attr], src->data[attr]);
   }
}


/**
 * Flatshade tri.  Required for clipping and when unfilled tris are
 * active, otherwise handled by hardware.
 */
static void flatshade_tri( struct draw_stage *stage,
			   struct prim_header *header )
{
   struct prim_header tmp;

   tmp.det = header->det;
   tmp.edgeflags = header->edgeflags;
   tmp.v[0] = dup_vert(stage, header->v[0], 0);
   tmp.v[1] = dup_vert(stage, header->v[1], 1);
   tmp.v[2] = header->v[2];

   copy_colors2(stage, tmp.v[0], tmp.v[1], tmp.v[2]);
   
   stage->next->tri( stage->next, &tmp );
}


/**
 * Flatshade line.  Required for clipping.
 */
static void flatshade_line( struct draw_stage *stage,
			    struct prim_header *header )
{
   struct prim_header tmp;

   tmp.v[0] = dup_vert(stage, header->v[0], 0);
   tmp.v[1] = header->v[1];

   copy_colors(stage, tmp.v[0], tmp.v[1]);
   
   stage->next->line( stage->next, &tmp );
}


static void flatshade_point( struct draw_stage *stage,
                             struct prim_header *header )
{
   stage->next->point( stage->next, header );
}


static void flatshade_init_state( struct draw_stage *stage )
{
   struct flat_stage *flat = flat_stage(stage);
   const struct draw_vertex_shader *vs = stage->draw->vertex_shader;
   uint i;

   /* Find which vertex shader outputs are colors, make a list */
   flat->num_color_attribs = 0;
   for (i = 0; i < vs->info.num_outputs; i++) {
      if (vs->info.output_semantic_name[i] == TGSI_SEMANTIC_COLOR ||
          vs->info.output_semantic_name[i] == TGSI_SEMANTIC_BCOLOR) {
         flat->color_attribs[flat->num_color_attribs++] = i;
      }
   }

   stage->line = flatshade_line;
   stage->tri = flatshade_tri;
}

static void flatshade_first_tri( struct draw_stage *stage,
				 struct prim_header *header )
{
   flatshade_init_state( stage );
   stage->tri( stage, header );
}

static void flatshade_first_line( struct draw_stage *stage,
				  struct prim_header *header )
{
   flatshade_init_state( stage );
   stage->line( stage, header );
}


static void flatshade_flush( struct draw_stage *stage, 
			     unsigned flags )
{
   stage->tri = flatshade_first_tri;
   stage->line = flatshade_first_line;
   stage->next->flush( stage->next, flags );
}


static void flatshade_reset_stipple_counter( struct draw_stage *stage )
{
   stage->next->reset_stipple_counter( stage->next );
}


static void flatshade_destroy( struct draw_stage *stage )
{
   draw_free_temp_verts( stage );
   FREE( stage );
}


/**
 * Create flatshading drawing stage.
 */
struct draw_stage *draw_flatshade_stage( struct draw_context *draw )
{
   struct flat_stage *flatshade = CALLOC_STRUCT(flat_stage);

   draw_alloc_temp_verts( &flatshade->stage, 2 );

   flatshade->stage.draw = draw;
   flatshade->stage.next = NULL;
   flatshade->stage.point = flatshade_point;
   flatshade->stage.line = flatshade_first_line;
   flatshade->stage.tri = flatshade_first_tri;
   flatshade->stage.flush = flatshade_flush;
   flatshade->stage.reset_stipple_counter = flatshade_reset_stipple_counter;
   flatshade->stage.destroy = flatshade_destroy;

   return &flatshade->stage;
}