1 /************************************************************************** 2 * 3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. 4 * All Rights Reserved. 5 * 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: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 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. 25 * 26 **************************************************************************/ 27 28 /** 29 * \brief Drawing stage for handling glPolygonMode(line/point). 30 * Convert triangles to points or lines as needed. 31 */ 32 33 /* Authors: Keith Whitwell <keith (at) tungstengraphics.com> 34 */ 35 36 #include "util/u_memory.h" 37 #include "pipe/p_defines.h" 38 #include "draw_private.h" 39 #include "draw_pipe.h" 40 41 42 struct unfilled_stage { 43 struct draw_stage stage; 44 45 /** [0] = front face, [1] = back face. 46 * legal values: PIPE_POLYGON_MODE_FILL, PIPE_POLYGON_MODE_LINE, 47 * and PIPE_POLYGON_MODE_POINT, 48 */ 49 unsigned mode[2]; 50 }; 51 52 53 static INLINE struct unfilled_stage *unfilled_stage( struct draw_stage *stage ) 54 { 55 return (struct unfilled_stage *)stage; 56 } 57 58 59 60 static void point( struct draw_stage *stage, 61 struct vertex_header *v0 ) 62 { 63 struct prim_header tmp; 64 tmp.v[0] = v0; 65 stage->next->point( stage->next, &tmp ); 66 } 67 68 static void line( struct draw_stage *stage, 69 struct vertex_header *v0, 70 struct vertex_header *v1 ) 71 { 72 struct prim_header tmp; 73 tmp.v[0] = v0; 74 tmp.v[1] = v1; 75 stage->next->line( stage->next, &tmp ); 76 } 77 78 79 static void points( struct draw_stage *stage, 80 struct prim_header *header ) 81 { 82 struct vertex_header *v0 = header->v[0]; 83 struct vertex_header *v1 = header->v[1]; 84 struct vertex_header *v2 = header->v[2]; 85 86 if ((header->flags & DRAW_PIPE_EDGE_FLAG_0) && v0->edgeflag) point( stage, v0 ); 87 if ((header->flags & DRAW_PIPE_EDGE_FLAG_1) && v1->edgeflag) point( stage, v1 ); 88 if ((header->flags & DRAW_PIPE_EDGE_FLAG_2) && v2->edgeflag) point( stage, v2 ); 89 } 90 91 92 static void lines( struct draw_stage *stage, 93 struct prim_header *header ) 94 { 95 struct vertex_header *v0 = header->v[0]; 96 struct vertex_header *v1 = header->v[1]; 97 struct vertex_header *v2 = header->v[2]; 98 99 if (header->flags & DRAW_PIPE_RESET_STIPPLE) 100 stage->next->reset_stipple_counter( stage->next ); 101 102 if ((header->flags & DRAW_PIPE_EDGE_FLAG_2) && v2->edgeflag) line( stage, v2, v0 ); 103 if ((header->flags & DRAW_PIPE_EDGE_FLAG_0) && v0->edgeflag) line( stage, v0, v1 ); 104 if ((header->flags & DRAW_PIPE_EDGE_FLAG_1) && v1->edgeflag) line( stage, v1, v2 ); 105 } 106 107 108 /** For debugging */ 109 static void 110 print_header_flags(unsigned flags) 111 { 112 debug_printf("header->flags = "); 113 if (flags & DRAW_PIPE_RESET_STIPPLE) 114 debug_printf("RESET_STIPPLE "); 115 if (flags & DRAW_PIPE_EDGE_FLAG_0) 116 debug_printf("EDGE_FLAG_0 "); 117 if (flags & DRAW_PIPE_EDGE_FLAG_1) 118 debug_printf("EDGE_FLAG_1 "); 119 if (flags & DRAW_PIPE_EDGE_FLAG_2) 120 debug_printf("EDGE_FLAG_2 "); 121 debug_printf("\n"); 122 } 123 124 125 /* Unfilled tri: 126 * 127 * Note edgeflags in the vertex struct is not sufficient as we will 128 * need to manipulate them when decomposing primitives. 129 * 130 * We currently keep the vertex edgeflag and primitive edgeflag mask 131 * separate until the last possible moment. 132 */ 133 static void unfilled_tri( struct draw_stage *stage, 134 struct prim_header *header ) 135 { 136 struct unfilled_stage *unfilled = unfilled_stage(stage); 137 unsigned cw = header->det >= 0.0; 138 unsigned mode = unfilled->mode[cw]; 139 140 if (0) 141 print_header_flags(header->flags); 142 143 switch (mode) { 144 case PIPE_POLYGON_MODE_FILL: 145 stage->next->tri( stage->next, header ); 146 break; 147 case PIPE_POLYGON_MODE_LINE: 148 lines( stage, header ); 149 break; 150 case PIPE_POLYGON_MODE_POINT: 151 points( stage, header ); 152 break; 153 default: 154 assert(0); 155 } 156 } 157 158 159 static void unfilled_first_tri( struct draw_stage *stage, 160 struct prim_header *header ) 161 { 162 struct unfilled_stage *unfilled = unfilled_stage(stage); 163 const struct pipe_rasterizer_state *rast = stage->draw->rasterizer; 164 165 unfilled->mode[0] = rast->front_ccw ? rast->fill_front : rast->fill_back; 166 unfilled->mode[1] = rast->front_ccw ? rast->fill_back : rast->fill_front; 167 168 stage->tri = unfilled_tri; 169 stage->tri( stage, header ); 170 } 171 172 173 174 static void unfilled_flush( struct draw_stage *stage, 175 unsigned flags ) 176 { 177 stage->next->flush( stage->next, flags ); 178 179 stage->tri = unfilled_first_tri; 180 } 181 182 183 static void unfilled_reset_stipple_counter( struct draw_stage *stage ) 184 { 185 stage->next->reset_stipple_counter( stage->next ); 186 } 187 188 189 static void unfilled_destroy( struct draw_stage *stage ) 190 { 191 draw_free_temp_verts( stage ); 192 FREE( stage ); 193 } 194 195 196 /** 197 * Create unfilled triangle stage. 198 */ 199 struct draw_stage *draw_unfilled_stage( struct draw_context *draw ) 200 { 201 struct unfilled_stage *unfilled = CALLOC_STRUCT(unfilled_stage); 202 if (unfilled == NULL) 203 goto fail; 204 205 unfilled->stage.draw = draw; 206 unfilled->stage.name = "unfilled"; 207 unfilled->stage.next = NULL; 208 unfilled->stage.tmp = NULL; 209 unfilled->stage.point = draw_pipe_passthrough_point; 210 unfilled->stage.line = draw_pipe_passthrough_line; 211 unfilled->stage.tri = unfilled_first_tri; 212 unfilled->stage.flush = unfilled_flush; 213 unfilled->stage.reset_stipple_counter = unfilled_reset_stipple_counter; 214 unfilled->stage.destroy = unfilled_destroy; 215 216 if (!draw_alloc_temp_verts( &unfilled->stage, 0 )) 217 goto fail; 218 219 return &unfilled->stage; 220 221 fail: 222 if (unfilled) 223 unfilled->stage.destroy( &unfilled->stage ); 224 225 return NULL; 226 } 227