1 /* 2 * Mesa 3-D graphics library 3 * Version: 7.1 4 * 5 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a 8 * copy of this software and associated documentation files (the "Software"), 9 * to deal in the Software without restriction, including without limitation 10 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 11 * and/or sell copies of the Software, and to permit persons to whom the 12 * Software is furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included 15 * in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23 */ 24 25 26 #include "main/glheader.h" 27 #include "main/colormac.h" 28 #include "main/feedback.h" 29 #include "main/light.h" 30 #include "main/macros.h" 31 #include "main/simple_list.h" 32 #include "main/mtypes.h" 33 34 #include "math/m_matrix.h" 35 #include "tnl/tnl.h" 36 37 38 39 /** 40 * Clip a point against the view volume. 41 * 42 * \param v vertex vector describing the point to clip. 43 * 44 * \return zero if outside view volume, or one if inside. 45 */ 46 static GLuint 47 viewclip_point_xy( const GLfloat v[] ) 48 { 49 if ( v[0] > v[3] || v[0] < -v[3] 50 || v[1] > v[3] || v[1] < -v[3] ) { 51 return 0; 52 } 53 else { 54 return 1; 55 } 56 } 57 58 59 /** 60 * Clip a point against the far/near Z clipping planes. 61 * 62 * \param v vertex vector describing the point to clip. 63 * 64 * \return zero if outside view volume, or one if inside. 65 */ 66 static GLuint 67 viewclip_point_z( const GLfloat v[] ) 68 { 69 if (v[2] > v[3] || v[2] < -v[3] ) { 70 return 0; 71 } 72 else { 73 return 1; 74 } 75 } 76 77 78 /** 79 * Clip a point against the user clipping planes. 80 * 81 * \param ctx GL context. 82 * \param v vertex vector describing the point to clip. 83 * 84 * \return zero if the point was clipped, or one otherwise. 85 */ 86 static GLuint 87 userclip_point( struct gl_context *ctx, const GLfloat v[] ) 88 { 89 GLuint p; 90 91 for (p = 0; p < ctx->Const.MaxClipPlanes; p++) { 92 if (ctx->Transform.ClipPlanesEnabled & (1 << p)) { 93 GLfloat dot = v[0] * ctx->Transform._ClipUserPlane[p][0] 94 + v[1] * ctx->Transform._ClipUserPlane[p][1] 95 + v[2] * ctx->Transform._ClipUserPlane[p][2] 96 + v[3] * ctx->Transform._ClipUserPlane[p][3]; 97 if (dot < 0.0F) { 98 return 0; 99 } 100 } 101 } 102 103 return 1; 104 } 105 106 107 /** 108 * Compute lighting for the raster position. RGB modes computed. 109 * \param ctx the context 110 * \param vertex vertex location 111 * \param normal normal vector 112 * \param Rcolor returned color 113 * \param Rspec returned specular color (if separate specular enabled) 114 */ 115 static void 116 shade_rastpos(struct gl_context *ctx, 117 const GLfloat vertex[4], 118 const GLfloat normal[3], 119 GLfloat Rcolor[4], 120 GLfloat Rspec[4]) 121 { 122 /*const*/ GLfloat (*base)[3] = ctx->Light._BaseColor; 123 const struct gl_light *light; 124 GLfloat diffuseColor[4], specularColor[4]; /* for RGB mode only */ 125 126 COPY_3V(diffuseColor, base[0]); 127 diffuseColor[3] = CLAMP( 128 ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3], 0.0F, 1.0F ); 129 ASSIGN_4V(specularColor, 0.0, 0.0, 0.0, 1.0); 130 131 foreach (light, &ctx->Light.EnabledList) { 132 GLfloat attenuation = 1.0; 133 GLfloat VP[3]; /* vector from vertex to light pos */ 134 GLfloat n_dot_VP; 135 GLfloat diffuseContrib[3], specularContrib[3]; 136 137 if (!(light->_Flags & LIGHT_POSITIONAL)) { 138 /* light at infinity */ 139 COPY_3V(VP, light->_VP_inf_norm); 140 attenuation = light->_VP_inf_spot_attenuation; 141 } 142 else { 143 /* local/positional light */ 144 GLfloat d; 145 146 /* VP = vector from vertex pos to light[i].pos */ 147 SUB_3V(VP, light->_Position, vertex); 148 /* d = length(VP) */ 149 d = (GLfloat) LEN_3FV( VP ); 150 if (d > 1.0e-6) { 151 /* normalize VP */ 152 GLfloat invd = 1.0F / d; 153 SELF_SCALE_SCALAR_3V(VP, invd); 154 } 155 156 /* atti */ 157 attenuation = 1.0F / (light->ConstantAttenuation + d * 158 (light->LinearAttenuation + d * 159 light->QuadraticAttenuation)); 160 161 if (light->_Flags & LIGHT_SPOT) { 162 GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection); 163 164 if (PV_dot_dir<light->_CosCutoff) { 165 continue; 166 } 167 else { 168 GLfloat spot = powf(PV_dot_dir, light->SpotExponent); 169 attenuation *= spot; 170 } 171 } 172 } 173 174 if (attenuation < 1e-3) 175 continue; 176 177 n_dot_VP = DOT3( normal, VP ); 178 179 if (n_dot_VP < 0.0F) { 180 ACC_SCALE_SCALAR_3V(diffuseColor, attenuation, light->_MatAmbient[0]); 181 continue; 182 } 183 184 /* Ambient + diffuse */ 185 COPY_3V(diffuseContrib, light->_MatAmbient[0]); 186 ACC_SCALE_SCALAR_3V(diffuseContrib, n_dot_VP, light->_MatDiffuse[0]); 187 188 /* Specular */ 189 { 190 const GLfloat *h; 191 GLfloat n_dot_h; 192 193 ASSIGN_3V(specularContrib, 0.0, 0.0, 0.0); 194 195 if (ctx->Light.Model.LocalViewer) { 196 GLfloat v[3]; 197 COPY_3V(v, vertex); 198 NORMALIZE_3FV(v); 199 SUB_3V(VP, VP, v); 200 NORMALIZE_3FV(VP); 201 h = VP; 202 } 203 else if (light->_Flags & LIGHT_POSITIONAL) { 204 ACC_3V(VP, ctx->_EyeZDir); 205 NORMALIZE_3FV(VP); 206 h = VP; 207 } 208 else { 209 h = light->_h_inf_norm; 210 } 211 212 n_dot_h = DOT3(normal, h); 213 214 if (n_dot_h > 0.0F) { 215 GLfloat shine; 216 GLfloat spec_coef; 217 218 shine = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_SHININESS][0]; 219 spec_coef = powf(n_dot_h, shine); 220 221 if (spec_coef > 1.0e-10) { 222 if (ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR) { 223 ACC_SCALE_SCALAR_3V( specularContrib, spec_coef, 224 light->_MatSpecular[0]); 225 } 226 else { 227 ACC_SCALE_SCALAR_3V( diffuseContrib, spec_coef, 228 light->_MatSpecular[0]); 229 } 230 } 231 } 232 } 233 234 ACC_SCALE_SCALAR_3V( diffuseColor, attenuation, diffuseContrib ); 235 ACC_SCALE_SCALAR_3V( specularColor, attenuation, specularContrib ); 236 } 237 238 Rcolor[0] = CLAMP(diffuseColor[0], 0.0F, 1.0F); 239 Rcolor[1] = CLAMP(diffuseColor[1], 0.0F, 1.0F); 240 Rcolor[2] = CLAMP(diffuseColor[2], 0.0F, 1.0F); 241 Rcolor[3] = CLAMP(diffuseColor[3], 0.0F, 1.0F); 242 Rspec[0] = CLAMP(specularColor[0], 0.0F, 1.0F); 243 Rspec[1] = CLAMP(specularColor[1], 0.0F, 1.0F); 244 Rspec[2] = CLAMP(specularColor[2], 0.0F, 1.0F); 245 Rspec[3] = CLAMP(specularColor[3], 0.0F, 1.0F); 246 } 247 248 249 /** 250 * Do texgen needed for glRasterPos. 251 * \param ctx rendering context 252 * \param vObj object-space vertex coordinate 253 * \param vEye eye-space vertex coordinate 254 * \param normal vertex normal 255 * \param unit texture unit number 256 * \param texcoord incoming texcoord and resulting texcoord 257 */ 258 static void 259 compute_texgen(struct gl_context *ctx, const GLfloat vObj[4], const GLfloat vEye[4], 260 const GLfloat normal[3], GLuint unit, GLfloat texcoord[4]) 261 { 262 const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit]; 263 264 /* always compute sphere map terms, just in case */ 265 GLfloat u[3], two_nu, rx, ry, rz, m, mInv; 266 COPY_3V(u, vEye); 267 NORMALIZE_3FV(u); 268 two_nu = 2.0F * DOT3(normal, u); 269 rx = u[0] - normal[0] * two_nu; 270 ry = u[1] - normal[1] * two_nu; 271 rz = u[2] - normal[2] * two_nu; 272 m = rx * rx + ry * ry + (rz + 1.0F) * (rz + 1.0F); 273 if (m > 0.0F) 274 mInv = 0.5F * INV_SQRTF(m); 275 else 276 mInv = 0.0F; 277 278 if (texUnit->TexGenEnabled & S_BIT) { 279 switch (texUnit->GenS.Mode) { 280 case GL_OBJECT_LINEAR: 281 texcoord[0] = DOT4(vObj, texUnit->GenS.ObjectPlane); 282 break; 283 case GL_EYE_LINEAR: 284 texcoord[0] = DOT4(vEye, texUnit->GenS.EyePlane); 285 break; 286 case GL_SPHERE_MAP: 287 texcoord[0] = rx * mInv + 0.5F; 288 break; 289 case GL_REFLECTION_MAP: 290 texcoord[0] = rx; 291 break; 292 case GL_NORMAL_MAP: 293 texcoord[0] = normal[0]; 294 break; 295 default: 296 _mesa_problem(ctx, "Bad S texgen in compute_texgen()"); 297 return; 298 } 299 } 300 301 if (texUnit->TexGenEnabled & T_BIT) { 302 switch (texUnit->GenT.Mode) { 303 case GL_OBJECT_LINEAR: 304 texcoord[1] = DOT4(vObj, texUnit->GenT.ObjectPlane); 305 break; 306 case GL_EYE_LINEAR: 307 texcoord[1] = DOT4(vEye, texUnit->GenT.EyePlane); 308 break; 309 case GL_SPHERE_MAP: 310 texcoord[1] = ry * mInv + 0.5F; 311 break; 312 case GL_REFLECTION_MAP: 313 texcoord[1] = ry; 314 break; 315 case GL_NORMAL_MAP: 316 texcoord[1] = normal[1]; 317 break; 318 default: 319 _mesa_problem(ctx, "Bad T texgen in compute_texgen()"); 320 return; 321 } 322 } 323 324 if (texUnit->TexGenEnabled & R_BIT) { 325 switch (texUnit->GenR.Mode) { 326 case GL_OBJECT_LINEAR: 327 texcoord[2] = DOT4(vObj, texUnit->GenR.ObjectPlane); 328 break; 329 case GL_EYE_LINEAR: 330 texcoord[2] = DOT4(vEye, texUnit->GenR.EyePlane); 331 break; 332 case GL_REFLECTION_MAP: 333 texcoord[2] = rz; 334 break; 335 case GL_NORMAL_MAP: 336 texcoord[2] = normal[2]; 337 break; 338 default: 339 _mesa_problem(ctx, "Bad R texgen in compute_texgen()"); 340 return; 341 } 342 } 343 344 if (texUnit->TexGenEnabled & Q_BIT) { 345 switch (texUnit->GenQ.Mode) { 346 case GL_OBJECT_LINEAR: 347 texcoord[3] = DOT4(vObj, texUnit->GenQ.ObjectPlane); 348 break; 349 case GL_EYE_LINEAR: 350 texcoord[3] = DOT4(vEye, texUnit->GenQ.EyePlane); 351 break; 352 default: 353 _mesa_problem(ctx, "Bad Q texgen in compute_texgen()"); 354 return; 355 } 356 } 357 } 358 359 360 /** 361 * glRasterPos transformation. Typically called via ctx->Driver.RasterPos(). 362 * XXX some of this code (such as viewport xform, clip testing and setting 363 * of ctx->Current.Raster* fields) could get lifted up into the 364 * main/rasterpos.c code. 365 * 366 * \param vObj vertex position in object space 367 */ 368 void 369 _tnl_RasterPos(struct gl_context *ctx, const GLfloat vObj[4]) 370 { 371 if (ctx->VertexProgram._Enabled) { 372 /* XXX implement this */ 373 _mesa_problem(ctx, "Vertex programs not implemented for glRasterPos"); 374 return; 375 } 376 else { 377 GLfloat eye[4], clip[4], ndc[3], d; 378 GLfloat *norm, eyenorm[3]; 379 GLfloat *objnorm = ctx->Current.Attrib[VERT_ATTRIB_NORMAL]; 380 381 /* apply modelview matrix: eye = MV * obj */ 382 TRANSFORM_POINT( eye, ctx->ModelviewMatrixStack.Top->m, vObj ); 383 /* apply projection matrix: clip = Proj * eye */ 384 TRANSFORM_POINT( clip, ctx->ProjectionMatrixStack.Top->m, eye ); 385 386 /* clip to view volume. */ 387 if (!ctx->Transform.DepthClamp) { 388 if (viewclip_point_z(clip) == 0) { 389 ctx->Current.RasterPosValid = GL_FALSE; 390 return; 391 } 392 } 393 if (!ctx->Transform.RasterPositionUnclipped) { 394 if (viewclip_point_xy(clip) == 0) { 395 ctx->Current.RasterPosValid = GL_FALSE; 396 return; 397 } 398 } 399 400 /* clip to user clipping planes */ 401 if (ctx->Transform.ClipPlanesEnabled && !userclip_point(ctx, clip)) { 402 ctx->Current.RasterPosValid = GL_FALSE; 403 return; 404 } 405 406 /* ndc = clip / W */ 407 d = (clip[3] == 0.0F) ? 1.0F : 1.0F / clip[3]; 408 ndc[0] = clip[0] * d; 409 ndc[1] = clip[1] * d; 410 ndc[2] = clip[2] * d; 411 /* wincoord = viewport_mapping(ndc) */ 412 ctx->Current.RasterPos[0] = (ndc[0] * ctx->Viewport._WindowMap.m[MAT_SX] 413 + ctx->Viewport._WindowMap.m[MAT_TX]); 414 ctx->Current.RasterPos[1] = (ndc[1] * ctx->Viewport._WindowMap.m[MAT_SY] 415 + ctx->Viewport._WindowMap.m[MAT_TY]); 416 ctx->Current.RasterPos[2] = (ndc[2] * ctx->Viewport._WindowMap.m[MAT_SZ] 417 + ctx->Viewport._WindowMap.m[MAT_TZ]) 418 / ctx->DrawBuffer->_DepthMaxF; 419 ctx->Current.RasterPos[3] = clip[3]; 420 421 if (ctx->Transform.DepthClamp) { 422 ctx->Current.RasterPos[3] = CLAMP(ctx->Current.RasterPos[3], 423 ctx->Viewport.Near, 424 ctx->Viewport.Far); 425 } 426 427 /* compute raster distance */ 428 if (ctx->Fog.FogCoordinateSource == GL_FOG_COORDINATE_EXT) 429 ctx->Current.RasterDistance = ctx->Current.Attrib[VERT_ATTRIB_FOG][0]; 430 else 431 ctx->Current.RasterDistance = 432 SQRTF( eye[0]*eye[0] + eye[1]*eye[1] + eye[2]*eye[2] ); 433 434 /* compute transformed normal vector (for lighting or texgen) */ 435 if (ctx->_NeedEyeCoords) { 436 const GLfloat *inv = ctx->ModelviewMatrixStack.Top->inv; 437 TRANSFORM_NORMAL( eyenorm, objnorm, inv ); 438 norm = eyenorm; 439 } 440 else { 441 norm = objnorm; 442 } 443 444 /* update raster color */ 445 if (ctx->Light.Enabled) { 446 /* lighting */ 447 shade_rastpos( ctx, vObj, norm, 448 ctx->Current.RasterColor, 449 ctx->Current.RasterSecondaryColor ); 450 } 451 else { 452 /* use current color */ 453 COPY_4FV(ctx->Current.RasterColor, 454 ctx->Current.Attrib[VERT_ATTRIB_COLOR0]); 455 COPY_4FV(ctx->Current.RasterSecondaryColor, 456 ctx->Current.Attrib[VERT_ATTRIB_COLOR1]); 457 } 458 459 /* texture coords */ 460 { 461 GLuint u; 462 for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) { 463 GLfloat tc[4]; 464 COPY_4V(tc, ctx->Current.Attrib[VERT_ATTRIB_TEX0 + u]); 465 if (ctx->Texture.Unit[u].TexGenEnabled) { 466 compute_texgen(ctx, vObj, eye, norm, u, tc); 467 } 468 TRANSFORM_POINT(ctx->Current.RasterTexCoords[u], 469 ctx->TextureMatrixStack[u].Top->m, tc); 470 } 471 } 472 473 ctx->Current.RasterPosValid = GL_TRUE; 474 } 475 476 if (ctx->RenderMode == GL_SELECT) { 477 _mesa_update_hitflag( ctx, ctx->Current.RasterPos[2] ); 478 } 479 } 480
