2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
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:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
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.
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"
34 #include "math/m_matrix.h"
40 * Clip a point against the view volume.
42 * \param v vertex vector describing the point to clip.
44 * \return zero if outside view volume, or one if inside.
47 viewclip_point_xy( const GLfloat v[] )
49 if ( v[0] > v[3] || v[0] < -v[3]
50 || v[1] > v[3] || v[1] < -v[3] ) {
60 * Clip a point against the far/near Z clipping planes.
62 * \param v vertex vector describing the point to clip.
64 * \return zero if outside view volume, or one if inside.
67 viewclip_point_z( const GLfloat v[] )
69 if (v[2] > v[3] || v[2] < -v[3] ) {
79 * Clip a point against the user clipping planes.
81 * \param ctx GL context.
82 * \param v vertex vector describing the point to clip.
84 * \return zero if the point was clipped, or one otherwise.
87 userclip_point( struct gl_context *ctx, const GLfloat v[] )
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];
108 * Compute lighting for the raster position. Both RGB and CI 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 * \param Rindex returned color index
117 shade_rastpos(struct gl_context *ctx,
118 const GLfloat vertex[4],
119 const GLfloat normal[3],
123 /*const*/ GLfloat (*base)[3] = ctx->Light._BaseColor;
124 const struct gl_light *light;
125 GLfloat diffuseColor[4], specularColor[4]; /* for RGB mode only */
126 GLfloat diffuseCI = 0.0, specularCI = 0.0; /* for CI mode only */
128 _mesa_validate_all_lighting_tables( ctx );
130 COPY_3V(diffuseColor, base[0]);
131 diffuseColor[3] = CLAMP(
132 ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3], 0.0F, 1.0F );
133 ASSIGN_4V(specularColor, 0.0, 0.0, 0.0, 1.0);
135 foreach (light, &ctx->Light.EnabledList) {
136 GLfloat attenuation = 1.0;
137 GLfloat VP[3]; /* vector from vertex to light pos */
139 GLfloat diffuseContrib[3], specularContrib[3];
141 if (!(light->_Flags & LIGHT_POSITIONAL)) {
142 /* light at infinity */
143 COPY_3V(VP, light->_VP_inf_norm);
144 attenuation = light->_VP_inf_spot_attenuation;
147 /* local/positional light */
150 /* VP = vector from vertex pos to light[i].pos */
151 SUB_3V(VP, light->_Position, vertex);
153 d = (GLfloat) LEN_3FV( VP );
156 GLfloat invd = 1.0F / d;
157 SELF_SCALE_SCALAR_3V(VP, invd);
161 attenuation = 1.0F / (light->ConstantAttenuation + d *
162 (light->LinearAttenuation + d *
163 light->QuadraticAttenuation));
165 if (light->_Flags & LIGHT_SPOT) {
166 GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection);
168 if (PV_dot_dir<light->_CosCutoff) {
172 double x = PV_dot_dir * (EXP_TABLE_SIZE-1);
174 GLfloat spot = (GLfloat) (light->_SpotExpTable[k][0]
175 + (x-k)*light->_SpotExpTable[k][1]);
181 if (attenuation < 1e-3)
184 n_dot_VP = DOT3( normal, VP );
186 if (n_dot_VP < 0.0F) {
187 ACC_SCALE_SCALAR_3V(diffuseColor, attenuation, light->_MatAmbient[0]);
191 /* Ambient + diffuse */
192 COPY_3V(diffuseContrib, light->_MatAmbient[0]);
193 ACC_SCALE_SCALAR_3V(diffuseContrib, n_dot_VP, light->_MatDiffuse[0]);
194 diffuseCI += n_dot_VP * light->_dli * attenuation;
201 ASSIGN_3V(specularContrib, 0.0, 0.0, 0.0);
203 if (ctx->Light.Model.LocalViewer) {
211 else if (light->_Flags & LIGHT_POSITIONAL) {
212 ACC_3V(VP, ctx->_EyeZDir);
217 h = light->_h_inf_norm;
220 n_dot_h = DOT3(normal, h);
222 if (n_dot_h > 0.0F) {
224 GET_SHINE_TAB_ENTRY( ctx->_ShineTable[0], n_dot_h, spec_coef );
226 if (spec_coef > 1.0e-10) {
227 if (ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR) {
228 ACC_SCALE_SCALAR_3V( specularContrib, spec_coef,
229 light->_MatSpecular[0]);
232 ACC_SCALE_SCALAR_3V( diffuseContrib, spec_coef,
233 light->_MatSpecular[0]);
235 /*assert(light->_sli > 0.0);*/
236 specularCI += spec_coef * light->_sli * attenuation;
241 ACC_SCALE_SCALAR_3V( diffuseColor, attenuation, diffuseContrib );
242 ACC_SCALE_SCALAR_3V( specularColor, attenuation, specularContrib );
245 Rcolor[0] = CLAMP(diffuseColor[0], 0.0F, 1.0F);
246 Rcolor[1] = CLAMP(diffuseColor[1], 0.0F, 1.0F);
247 Rcolor[2] = CLAMP(diffuseColor[2], 0.0F, 1.0F);
248 Rcolor[3] = CLAMP(diffuseColor[3], 0.0F, 1.0F);
249 Rspec[0] = CLAMP(specularColor[0], 0.0F, 1.0F);
250 Rspec[1] = CLAMP(specularColor[1], 0.0F, 1.0F);
251 Rspec[2] = CLAMP(specularColor[2], 0.0F, 1.0F);
252 Rspec[3] = CLAMP(specularColor[3], 0.0F, 1.0F);
257 * Do texgen needed for glRasterPos.
258 * \param ctx rendering context
259 * \param vObj object-space vertex coordinate
260 * \param vEye eye-space vertex coordinate
261 * \param normal vertex normal
262 * \param unit texture unit number
263 * \param texcoord incoming texcoord and resulting texcoord
266 compute_texgen(struct gl_context *ctx, const GLfloat vObj[4], const GLfloat vEye[4],
267 const GLfloat normal[3], GLuint unit, GLfloat texcoord[4])
269 const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
271 /* always compute sphere map terms, just in case */
272 GLfloat u[3], two_nu, rx, ry, rz, m, mInv;
275 two_nu = 2.0F * DOT3(normal, u);
276 rx = u[0] - normal[0] * two_nu;
277 ry = u[1] - normal[1] * two_nu;
278 rz = u[2] - normal[2] * two_nu;
279 m = rx * rx + ry * ry + (rz + 1.0F) * (rz + 1.0F);
281 mInv = 0.5F * _mesa_inv_sqrtf(m);
285 if (texUnit->TexGenEnabled & S_BIT) {
286 switch (texUnit->GenS.Mode) {
287 case GL_OBJECT_LINEAR:
288 texcoord[0] = DOT4(vObj, texUnit->GenS.ObjectPlane);
291 texcoord[0] = DOT4(vEye, texUnit->GenS.EyePlane);
294 texcoord[0] = rx * mInv + 0.5F;
296 case GL_REFLECTION_MAP:
300 texcoord[0] = normal[0];
303 _mesa_problem(ctx, "Bad S texgen in compute_texgen()");
308 if (texUnit->TexGenEnabled & T_BIT) {
309 switch (texUnit->GenT.Mode) {
310 case GL_OBJECT_LINEAR:
311 texcoord[1] = DOT4(vObj, texUnit->GenT.ObjectPlane);
314 texcoord[1] = DOT4(vEye, texUnit->GenT.EyePlane);
317 texcoord[1] = ry * mInv + 0.5F;
319 case GL_REFLECTION_MAP:
323 texcoord[1] = normal[1];
326 _mesa_problem(ctx, "Bad T texgen in compute_texgen()");
331 if (texUnit->TexGenEnabled & R_BIT) {
332 switch (texUnit->GenR.Mode) {
333 case GL_OBJECT_LINEAR:
334 texcoord[2] = DOT4(vObj, texUnit->GenR.ObjectPlane);
337 texcoord[2] = DOT4(vEye, texUnit->GenR.EyePlane);
339 case GL_REFLECTION_MAP:
343 texcoord[2] = normal[2];
346 _mesa_problem(ctx, "Bad R texgen in compute_texgen()");
351 if (texUnit->TexGenEnabled & Q_BIT) {
352 switch (texUnit->GenQ.Mode) {
353 case GL_OBJECT_LINEAR:
354 texcoord[3] = DOT4(vObj, texUnit->GenQ.ObjectPlane);
357 texcoord[3] = DOT4(vEye, texUnit->GenQ.EyePlane);
360 _mesa_problem(ctx, "Bad Q texgen in compute_texgen()");
368 * glRasterPos transformation. Typically called via ctx->Driver.RasterPos().
369 * XXX some of this code (such as viewport xform, clip testing and setting
370 * of ctx->Current.Raster* fields) could get lifted up into the
371 * main/rasterpos.c code.
373 * \param vObj vertex position in object space
376 _tnl_RasterPos(struct gl_context *ctx, const GLfloat vObj[4])
378 if (ctx->VertexProgram._Enabled) {
379 /* XXX implement this */
380 _mesa_problem(ctx, "Vertex programs not implemented for glRasterPos");
384 GLfloat eye[4], clip[4], ndc[3], d;
385 GLfloat *norm, eyenorm[3];
386 GLfloat *objnorm = ctx->Current.Attrib[VERT_ATTRIB_NORMAL];
388 /* apply modelview matrix: eye = MV * obj */
389 TRANSFORM_POINT( eye, ctx->ModelviewMatrixStack.Top->m, vObj );
390 /* apply projection matrix: clip = Proj * eye */
391 TRANSFORM_POINT( clip, ctx->ProjectionMatrixStack.Top->m, eye );
393 /* clip to view volume. */
394 if (!ctx->Transform.DepthClamp) {
395 if (viewclip_point_z(clip) == 0) {
396 ctx->Current.RasterPosValid = GL_FALSE;
400 if (!ctx->Transform.RasterPositionUnclipped) {
401 if (viewclip_point_xy(clip) == 0) {
402 ctx->Current.RasterPosValid = GL_FALSE;
407 /* clip to user clipping planes */
408 if (ctx->Transform.ClipPlanesEnabled && !userclip_point(ctx, clip)) {
409 ctx->Current.RasterPosValid = GL_FALSE;
414 d = (clip[3] == 0.0F) ? 1.0F : 1.0F / clip[3];
415 ndc[0] = clip[0] * d;
416 ndc[1] = clip[1] * d;
417 ndc[2] = clip[2] * d;
418 /* wincoord = viewport_mapping(ndc) */
419 ctx->Current.RasterPos[0] = (ndc[0] * ctx->Viewport._WindowMap.m[MAT_SX]
420 + ctx->Viewport._WindowMap.m[MAT_TX]);
421 ctx->Current.RasterPos[1] = (ndc[1] * ctx->Viewport._WindowMap.m[MAT_SY]
422 + ctx->Viewport._WindowMap.m[MAT_TY]);
423 ctx->Current.RasterPos[2] = (ndc[2] * ctx->Viewport._WindowMap.m[MAT_SZ]
424 + ctx->Viewport._WindowMap.m[MAT_TZ])
425 / ctx->DrawBuffer->_DepthMaxF;
426 ctx->Current.RasterPos[3] = clip[3];
428 if (ctx->Transform.DepthClamp) {
429 ctx->Current.RasterPos[3] = CLAMP(ctx->Current.RasterPos[3],
434 /* compute raster distance */
435 if (ctx->Fog.FogCoordinateSource == GL_FOG_COORDINATE_EXT)
436 ctx->Current.RasterDistance = ctx->Current.Attrib[VERT_ATTRIB_FOG][0];
438 ctx->Current.RasterDistance =
439 SQRTF( eye[0]*eye[0] + eye[1]*eye[1] + eye[2]*eye[2] );
441 /* compute transformed normal vector (for lighting or texgen) */
442 if (ctx->_NeedEyeCoords) {
443 const GLfloat *inv = ctx->ModelviewMatrixStack.Top->inv;
444 TRANSFORM_NORMAL( eyenorm, objnorm, inv );
451 /* update raster color */
452 if (ctx->Light.Enabled) {
454 shade_rastpos( ctx, vObj, norm,
455 ctx->Current.RasterColor,
456 ctx->Current.RasterSecondaryColor );
459 /* use current color */
460 COPY_4FV(ctx->Current.RasterColor,
461 ctx->Current.Attrib[VERT_ATTRIB_COLOR0]);
462 COPY_4FV(ctx->Current.RasterSecondaryColor,
463 ctx->Current.Attrib[VERT_ATTRIB_COLOR1]);
469 for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
471 COPY_4V(tc, ctx->Current.Attrib[VERT_ATTRIB_TEX0 + u]);
472 if (ctx->Texture.Unit[u].TexGenEnabled) {
473 compute_texgen(ctx, vObj, eye, norm, u, tc);
475 TRANSFORM_POINT(ctx->Current.RasterTexCoords[u],
476 ctx->TextureMatrixStack[u].Top->m, tc);
480 ctx->Current.RasterPosValid = GL_TRUE;
483 if (ctx->RenderMode == GL_SELECT) {
484 _mesa_update_hitflag( ctx, ctx->Current.RasterPos[2] );