summaryrefslogtreecommitdiff
path: root/src/gallium/auxiliary/draw/draw_pt_decompose.h
blob: 52f9593d46ed535f199cecab6f7b7641a918aa5f (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


static void FUNC( ARGS,
                  unsigned count )
{
   LOCAL_VARS;

   switch (prim) {
   case PIPE_PRIM_POINTS:
      for (i = 0; i < count; i ++) {
	 POINT( (i + 0) );
      }
      break;

   case PIPE_PRIM_LINES:
      for (i = 0; i+1 < count; i += 2) {
         LINE( DRAW_PIPE_RESET_STIPPLE,
               (i + 0),
               (i + 1));
      }
      break;

   case PIPE_PRIM_LINE_LOOP:
      if (count >= 2) {
         flags = DRAW_PIPE_RESET_STIPPLE;

         for (i = 1; i < count; i++, flags = 0) {
            LINE( flags,
                  (i - 1),
                  (i ));
         }

	 LINE( flags,
               (i - 1),
               (0 ));
      }
      break;

   case PIPE_PRIM_LINE_STRIP:
      flags = DRAW_PIPE_RESET_STIPPLE;
      for (i = 1; i < count; i++, flags = 0) {
         LINE( flags,
               (i - 1),
               (i ));
      }
      break;

   case PIPE_PRIM_TRIANGLES:
      for (i = 0; i+2 < count; i += 3) {
         TRIANGLE( DRAW_PIPE_RESET_STIPPLE | DRAW_PIPE_EDGE_FLAG_ALL,
                   (i + 0),
                   (i + 1),
                   (i + 2 ));
      }
      break;

   case PIPE_PRIM_TRIANGLE_STRIP:
      if (flatfirst) {
         for (i = 0; i+2 < count; i++) {
            /* Emit first triangle vertex as first triangle vertex */
            TRIANGLE( DRAW_PIPE_RESET_STIPPLE | DRAW_PIPE_EDGE_FLAG_ALL,
                      (i + 0),
                      (i + 1 + (i&1)),
                      (i + 2 - (i&1)) );
         }
      }
      else {
         for (i = 0; i+2 < count; i++) {
            /* Emit last triangle vertex as last triangle vertex */
            TRIANGLE( DRAW_PIPE_RESET_STIPPLE | DRAW_PIPE_EDGE_FLAG_ALL,
                      (i + 0 + (i&1)),
                      (i + 1 - (i&1)),
                      (i + 2 ));
         }
      }
      break;

   case PIPE_PRIM_TRIANGLE_FAN:
      if (count >= 3) {
         if (flatfirst) {
            for (i = 0; i+2 < count; i++) {
               TRIANGLE( DRAW_PIPE_RESET_STIPPLE | DRAW_PIPE_EDGE_FLAG_ALL,
                         (i + 1),
                         (i + 2),
                         0 );
            }
         }
         else {
            for (i = 0; i+2 < count; i++) {
               TRIANGLE( DRAW_PIPE_RESET_STIPPLE | DRAW_PIPE_EDGE_FLAG_ALL,
                         (0),
                         (i + 1),
                         (i + 2 ));
            }
         }
      }
      break;


   case PIPE_PRIM_QUADS:
      /* GL quads don't follow provoking vertex convention */
      if (flatfirst) {
         for (i = 0; i+3 < count; i += 4) {
            /* emit last quad vertex as first triangle vertex */
            QUAD_FIRST_PV( (i + 3),
                           (i + 0),
                           (i + 1),
                           (i + 2) );
         }
      }
      else {
         for (i = 0; i+3 < count; i += 4) {
            /* emit last quad vertex as last triangle vertex */
            QUAD_LAST_PV( (i + 0),
                          (i + 1),
                          (i + 2),
                          (i + 3) );
         }
      }
      break;

   case PIPE_PRIM_QUAD_STRIP:
      /* GL quad strips don't follow provoking vertex convention */
      if (flatfirst) {
         for (i = 0; i+3 < count; i += 2) {
            /* emit last quad vertex as first triangle vertex */
            QUAD_FIRST_PV( (i + 3),
                           (i + 2),
                           (i + 0),
                           (i + 1) );

         }
      }
      else {
         for (i = 0; i+3 < count; i += 2) {
            /* emit last quad vertex as last triangle vertex */
            QUAD_LAST_PV( (i + 2),
                          (i + 0),
                          (i + 1),
                          (i + 3) );
         }
      }
      break;

   case PIPE_PRIM_POLYGON:
      /* GL polygons don't follow provoking vertex convention */
      {
         /* These bitflags look a little odd because we submit the
          * vertices as (1,2,0) to satisfy flatshade requirements.
          */
         const ushort edge_first  = DRAW_PIPE_EDGE_FLAG_2;
         const ushort edge_middle = DRAW_PIPE_EDGE_FLAG_0;
         const ushort edge_last   = DRAW_PIPE_EDGE_FLAG_1;

         flags = DRAW_PIPE_RESET_STIPPLE | edge_first | edge_middle;

	 for (i = 0; i+2 < count; i++, flags = edge_middle) {

            if (i + 3 == count)
               flags |= edge_last;

            if (flatfirst) {
               /* emit first polygon vertex as first triangle vertex */
               TRIANGLE( flags,
                         (0),
                         (i + 1),
                         (i + 2) );
            }
            else {
               /* emit first polygon vertex as last triangle vertex */
               TRIANGLE( flags,
                         (i + 1),
                         (i + 2),
                         (0));
            }
	 }
      }
      break;

   default:
      assert(0);
      break;
   }

   FLUSH;
}


#undef TRIANGLE
#undef QUAD_FIRST_PV
#undef QUAD_LAST_PV
#undef POINT
#undef LINE
#undef FUNC