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 * glRasterPos implementation. Basically render a GL_POINT with our 30 * private draw module. Plug in a special "rasterpos" stage at the end 31 * of the 'draw' pipeline to capture the results and update the current 32 * raster pos attributes. 33 * 34 * Authors: 35 * Brian Paul 36 */ 37 38 39 #include "main/imports.h" 40 #include "main/macros.h" 41 #include "main/mfeatures.h" 42 #include "main/feedback.h" 43 44 #include "st_context.h" 45 #include "st_atom.h" 46 #include "st_draw.h" 47 #include "st_cb_rasterpos.h" 48 #include "draw/draw_context.h" 49 #include "draw/draw_pipe.h" 50 #include "vbo/vbo.h" 51 52 53 #if FEATURE_rastpos 54 55 /** 56 * Our special drawing pipeline stage (replaces rasterization). 57 */ 58 struct rastpos_stage 59 { 60 struct draw_stage stage; /**< Base class */ 61 struct gl_context *ctx; /**< Rendering context */ 62 63 /* vertex attrib info we can setup once and re-use */ 64 struct gl_client_array array[VERT_ATTRIB_MAX]; 65 const struct gl_client_array *arrays[VERT_ATTRIB_MAX]; 66 struct _mesa_prim prim; 67 }; 68 69 70 static INLINE struct rastpos_stage * 71 rastpos_stage( struct draw_stage *stage ) 72 { 73 return (struct rastpos_stage *) stage; 74 } 75 76 static void 77 rastpos_flush( struct draw_stage *stage, unsigned flags ) 78 { 79 /* no-op */ 80 } 81 82 static void 83 rastpos_reset_stipple_counter( struct draw_stage *stage ) 84 { 85 /* no-op */ 86 } 87 88 static void 89 rastpos_tri( struct draw_stage *stage, struct prim_header *prim ) 90 { 91 /* should never get here */ 92 assert(0); 93 } 94 95 static void 96 rastpos_line( struct draw_stage *stage, struct prim_header *prim ) 97 { 98 /* should never get here */ 99 assert(0); 100 } 101 102 static void 103 rastpos_destroy(struct draw_stage *stage) 104 { 105 free(stage); 106 } 107 108 109 /** 110 * Update a raster pos attribute from the vertex result if it's present, 111 * else copy the current attrib. 112 */ 113 static void 114 update_attrib(struct gl_context *ctx, const GLuint *outputMapping, 115 const struct vertex_header *vert, 116 GLfloat *dest, 117 GLuint result, GLuint defaultAttrib) 118 { 119 const GLfloat *src; 120 const GLuint k = outputMapping[result]; 121 if (k != ~0U) 122 src = vert->data[k]; 123 else 124 src = ctx->Current.Attrib[defaultAttrib]; 125 COPY_4V(dest, src); 126 } 127 128 129 /** 130 * Normally, this function would render a GL_POINT. 131 */ 132 static void 133 rastpos_point(struct draw_stage *stage, struct prim_header *prim) 134 { 135 struct rastpos_stage *rs = rastpos_stage(stage); 136 struct gl_context *ctx = rs->ctx; 137 struct st_context *st = st_context(ctx); 138 const GLfloat height = (GLfloat) ctx->DrawBuffer->Height; 139 const GLuint *outputMapping = st->vertex_result_to_slot; 140 const GLfloat *pos; 141 GLuint i; 142 143 /* if we get here, we didn't get clipped */ 144 ctx->Current.RasterPosValid = GL_TRUE; 145 146 /* update raster pos */ 147 pos = prim->v[0]->data[0]; 148 ctx->Current.RasterPos[0] = pos[0]; 149 if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) 150 ctx->Current.RasterPos[1] = height - pos[1]; /* invert Y */ 151 else 152 ctx->Current.RasterPos[1] = pos[1]; 153 ctx->Current.RasterPos[2] = pos[2]; 154 ctx->Current.RasterPos[3] = pos[3]; 155 156 /* update other raster attribs */ 157 update_attrib(ctx, outputMapping, prim->v[0], 158 ctx->Current.RasterColor, 159 VERT_RESULT_COL0, VERT_ATTRIB_COLOR0); 160 161 update_attrib(ctx, outputMapping, prim->v[0], 162 ctx->Current.RasterSecondaryColor, 163 VERT_RESULT_COL1, VERT_ATTRIB_COLOR1); 164 165 for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) { 166 update_attrib(ctx, outputMapping, prim->v[0], 167 ctx->Current.RasterTexCoords[i], 168 VERT_RESULT_TEX0 + i, VERT_ATTRIB_TEX0 + i); 169 } 170 171 if (ctx->RenderMode == GL_SELECT) { 172 _mesa_update_hitflag( ctx, ctx->Current.RasterPos[2] ); 173 } 174 } 175 176 177 /** 178 * Create rasterpos "drawing" stage. 179 */ 180 static struct rastpos_stage * 181 new_draw_rastpos_stage(struct gl_context *ctx, struct draw_context *draw) 182 { 183 struct rastpos_stage *rs = ST_CALLOC_STRUCT(rastpos_stage); 184 GLuint i; 185 186 rs->stage.draw = draw; 187 rs->stage.next = NULL; 188 rs->stage.point = rastpos_point; 189 rs->stage.line = rastpos_line; 190 rs->stage.tri = rastpos_tri; 191 rs->stage.flush = rastpos_flush; 192 rs->stage.destroy = rastpos_destroy; 193 rs->stage.reset_stipple_counter = rastpos_reset_stipple_counter; 194 rs->stage.destroy = rastpos_destroy; 195 rs->ctx = ctx; 196 197 for (i = 0; i < Elements(rs->array); i++) { 198 rs->array[i].Size = 4; 199 rs->array[i].Type = GL_FLOAT; 200 rs->array[i].Format = GL_RGBA; 201 rs->array[i].Stride = 0; 202 rs->array[i].StrideB = 0; 203 rs->array[i].Ptr = (GLubyte *) ctx->Current.Attrib[i]; 204 rs->array[i].Enabled = GL_TRUE; 205 rs->array[i].Normalized = GL_TRUE; 206 rs->array[i].BufferObj = NULL; 207 rs->arrays[i] = &rs->array[i]; 208 } 209 210 rs->prim.mode = GL_POINTS; 211 rs->prim.indexed = 0; 212 rs->prim.begin = 1; 213 rs->prim.end = 1; 214 rs->prim.weak = 0; 215 rs->prim.start = 0; 216 rs->prim.count = 1; 217 218 return rs; 219 } 220 221 222 static void 223 st_RasterPos(struct gl_context *ctx, const GLfloat v[4]) 224 { 225 struct st_context *st = st_context(ctx); 226 struct draw_context *draw = st->draw; 227 struct rastpos_stage *rs; 228 const struct gl_client_array **saved_arrays = ctx->Array._DrawArrays; 229 230 if (st->rastpos_stage) { 231 /* get rastpos stage info */ 232 rs = rastpos_stage(st->rastpos_stage); 233 } 234 else { 235 /* create rastpos draw stage */ 236 rs = new_draw_rastpos_stage(ctx, draw); 237 st->rastpos_stage = &rs->stage; 238 } 239 240 /* plug our rastpos stage into the draw module */ 241 draw_set_rasterize_stage(st->draw, st->rastpos_stage); 242 243 /* make sure everything's up to date */ 244 st_validate_state(st); 245 246 /* This will get set only if rastpos_point(), above, gets called */ 247 ctx->Current.RasterPosValid = GL_FALSE; 248 249 /* All vertex attribs but position were previously initialized above. 250 * Just plug in position pointer now. 251 */ 252 rs->array[0].Ptr = (GLubyte *) v; 253 254 /* Draw the point. 255 * 256 * Don't set DriverFlags.NewArray. 257 * st_feedback_draw_vbo doesn't check for that flag. */ 258 ctx->Array._DrawArrays = rs->arrays; 259 st_feedback_draw_vbo(ctx, &rs->prim, 1, NULL, GL_TRUE, 0, 1, 260 NULL); 261 ctx->Array._DrawArrays = saved_arrays; 262 263 /* restore draw's rasterization stage depending on rendermode */ 264 if (ctx->RenderMode == GL_FEEDBACK) { 265 draw_set_rasterize_stage(draw, st->feedback_stage); 266 } 267 else if (ctx->RenderMode == GL_SELECT) { 268 draw_set_rasterize_stage(draw, st->selection_stage); 269 } 270 } 271 272 273 274 void st_init_rasterpos_functions(struct dd_function_table *functions) 275 { 276 functions->RasterPos = st_RasterPos; 277 } 278 279 #endif /* FEATURE_rastpos */ 280