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1 /*
2  * Mesa 3-D graphics library
3  *
4  * Copyright (C) 1999-2006  Brian Paul   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 "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included
14  * in all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors:
25  *    Brian Paul Keith Whitwell <keithw@vmware.com>
26  */
27 
28 /*
29  * Regarding GL_NV_texgen_reflection:
30  *
31  * Portions of this software may use or implement intellectual
32  * property owned and licensed by NVIDIA Corporation. NVIDIA disclaims
33  * any and all warranties with respect to such intellectual property,
34  * including any use thereof or modifications thereto.
35  */
36 
37 #include "main/errors.h"
38 #include "main/glheader.h"
39 #include "main/macros.h"
40 
41 #include "main/mtypes.h"
42 
43 #include "math/m_xform.h"
44 
45 #include "t_context.h"
46 #include "t_pipeline.h"
47 
48 
49 /***********************************************************************
50  * Automatic texture coordinate generation (texgen) code.
51  */
52 
53 
54 struct texgen_stage_data;
55 
56 typedef void (*texgen_func)( struct gl_context *ctx,
57 			     struct texgen_stage_data *store,
58 			     GLuint unit);
59 
60 
61 struct texgen_stage_data {
62 
63    /* Per-texunit derived state.
64     */
65    GLuint TexgenSize[MAX_TEXTURE_COORD_UNITS];
66    texgen_func TexgenFunc[MAX_TEXTURE_COORD_UNITS];
67 
68    /* Temporary values used in texgen.
69     */
70    GLfloat (*tmp_f)[3];
71    GLfloat *tmp_m;
72 
73    /* Buffered outputs of the stage.
74     */
75    GLvector4f texcoord[MAX_TEXTURE_COORD_UNITS];
76 };
77 
78 
79 #define TEXGEN_STAGE_DATA(stage) ((struct texgen_stage_data *)stage->privatePtr)
80 
81 
82 
83 static GLuint all_bits[5] = {
84    0,
85    VEC_SIZE_1,
86    VEC_SIZE_2,
87    VEC_SIZE_3,
88    VEC_SIZE_4,
89 };
90 
91 #define VEC_SIZE_FLAGS (VEC_SIZE_1|VEC_SIZE_2|VEC_SIZE_3|VEC_SIZE_4)
92 
93 #define TEXGEN_NEED_M            (TEXGEN_SPHERE_MAP)
94 #define TEXGEN_NEED_F            (TEXGEN_SPHERE_MAP        | \
95 				  TEXGEN_REFLECTION_MAP_NV)
96 
97 
98 
build_m3(GLfloat f[][3],GLfloat m[],const GLvector4f * normal,const GLvector4f * eye)99 static void build_m3( GLfloat f[][3], GLfloat m[],
100 		      const GLvector4f *normal,
101 		      const GLvector4f *eye )
102 {
103    GLuint stride = eye->stride;
104    GLfloat *coord = (GLfloat *)eye->start;
105    GLuint count = eye->count;
106    const GLfloat *norm = normal->start;
107    GLuint i;
108 
109    for (i=0;i<count;i++,STRIDE_F(coord,stride),STRIDE_F(norm,normal->stride)) {
110       GLfloat u[3], two_nu, fx, fy, fz;
111       COPY_3V( u, coord );
112       NORMALIZE_3FV( u );
113       two_nu = 2.0F * DOT3(norm,u);
114       fx = f[i][0] = u[0] - norm[0] * two_nu;
115       fy = f[i][1] = u[1] - norm[1] * two_nu;
116       fz = f[i][2] = u[2] - norm[2] * two_nu;
117       m[i] = fx * fx + fy * fy + (fz + 1.0F) * (fz + 1.0F);
118       if (m[i] != 0.0F) {
119 	 m[i] = 0.5F * (1.0f / sqrtf(m[i]));
120       }
121    }
122 }
123 
124 
125 
build_m2(GLfloat f[][3],GLfloat m[],const GLvector4f * normal,const GLvector4f * eye)126 static void build_m2( GLfloat f[][3], GLfloat m[],
127 		      const GLvector4f *normal,
128 		      const GLvector4f *eye )
129 {
130    GLuint stride = eye->stride;
131    GLfloat *coord = eye->start;
132    GLuint count = eye->count;
133 
134    GLfloat *norm = normal->start;
135    GLuint i;
136 
137    for (i=0;i<count;i++,STRIDE_F(coord,stride),STRIDE_F(norm,normal->stride)) {
138       GLfloat u[3], two_nu, fx, fy, fz;
139       COPY_2V( u, coord );
140       u[2] = 0;
141       NORMALIZE_3FV( u );
142       two_nu = 2.0F * DOT3(norm,u);
143       fx = f[i][0] = u[0] - norm[0] * two_nu;
144       fy = f[i][1] = u[1] - norm[1] * two_nu;
145       fz = f[i][2] = u[2] - norm[2] * two_nu;
146       m[i] = fx * fx + fy * fy + (fz + 1.0F) * (fz + 1.0F);
147       if (m[i] != 0.0F) {
148 	 m[i] = 0.5F * (1.0f / sqrtf(m[i]));
149       }
150    }
151 }
152 
153 
154 
155 typedef void (*build_m_func)( GLfloat f[][3],
156 			      GLfloat m[],
157 			      const GLvector4f *normal,
158 			      const GLvector4f *eye );
159 
160 
161 static build_m_func build_m_tab[5] = {
162    NULL,
163    NULL,
164    build_m2,
165    build_m3,
166    build_m3
167 };
168 
169 
170 /* This is unusual in that we respect the stride of the output vector
171  * (f).  This allows us to pass in either a texcoord vector4f, or a
172  * temporary vector3f.
173  */
build_f3(GLfloat * f,GLuint fstride,const GLvector4f * normal,const GLvector4f * eye)174 static void build_f3( GLfloat *f,
175 		      GLuint fstride,
176 		      const GLvector4f *normal,
177 		      const GLvector4f *eye )
178 {
179    GLuint stride = eye->stride;
180    GLfloat *coord = eye->start;
181    GLuint count = eye->count;
182 
183    GLfloat *norm = normal->start;
184    GLuint i;
185 
186    for (i=0;i<count;i++) {
187       GLfloat u[3], two_nu;
188       COPY_3V( u, coord );
189       NORMALIZE_3FV( u );
190       two_nu = 2.0F * DOT3(norm,u);
191       f[0] = u[0] - norm[0] * two_nu;
192       f[1] = u[1] - norm[1] * two_nu;
193       f[2] = u[2] - norm[2] * two_nu;
194       STRIDE_F(coord,stride);
195       STRIDE_F(f,fstride);
196       STRIDE_F(norm, normal->stride);
197    }
198 }
199 
200 
build_f2(GLfloat * f,GLuint fstride,const GLvector4f * normal,const GLvector4f * eye)201 static void build_f2( GLfloat *f,
202 		      GLuint fstride,
203 		      const GLvector4f *normal,
204 		      const GLvector4f *eye )
205 {
206    GLuint stride = eye->stride;
207    GLfloat *coord = eye->start;
208    GLuint count = eye->count;
209    GLfloat *norm = normal->start;
210    GLuint i;
211 
212    for (i=0;i<count;i++) {
213 
214       GLfloat u[3], two_nu;
215       COPY_2V( u, coord );
216       u[2] = 0;
217       NORMALIZE_3FV( u );
218       two_nu = 2.0F * DOT3(norm,u);
219       f[0] = u[0] - norm[0] * two_nu;
220       f[1] = u[1] - norm[1] * two_nu;
221       f[2] = u[2] - norm[2] * two_nu;
222 
223       STRIDE_F(coord,stride);
224       STRIDE_F(f,fstride);
225       STRIDE_F(norm, normal->stride);
226    }
227 }
228 
229 typedef void (*build_f_func)( GLfloat *f,
230 			      GLuint fstride,
231 			      const GLvector4f *normal_vec,
232 			      const GLvector4f *eye );
233 
234 
235 
236 /* Just treat 4-vectors as 3-vectors.
237  */
238 static build_f_func build_f_tab[5] = {
239    NULL,
240    NULL,
241    build_f2,
242    build_f3,
243    build_f3
244 };
245 
246 
247 
248 /* Special case texgen functions.
249  */
texgen_reflection_map_nv(struct gl_context * ctx,struct texgen_stage_data * store,GLuint unit)250 static void texgen_reflection_map_nv( struct gl_context *ctx,
251 				      struct texgen_stage_data *store,
252 				      GLuint unit )
253 {
254    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
255    GLvector4f *in = VB->AttribPtr[VERT_ATTRIB_TEX0 + unit];
256    GLvector4f *out = &store->texcoord[unit];
257 
258    build_f_tab[VB->EyePtr->size]( out->start,
259 				  out->stride,
260 				  VB->AttribPtr[_TNL_ATTRIB_NORMAL],
261 				  VB->EyePtr );
262 
263    out->flags |= (in->flags & VEC_SIZE_FLAGS) | VEC_SIZE_3;
264    out->count = VB->Count;
265    out->size = MAX2(in->size, 3);
266    if (in->size == 4)
267       _mesa_copy_tab[0x8]( out, in );
268 }
269 
270 
271 
texgen_normal_map_nv(struct gl_context * ctx,struct texgen_stage_data * store,GLuint unit)272 static void texgen_normal_map_nv( struct gl_context *ctx,
273 				  struct texgen_stage_data *store,
274 				  GLuint unit )
275 {
276    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
277    GLvector4f *in = VB->AttribPtr[VERT_ATTRIB_TEX0 + unit];
278    GLvector4f *out = &store->texcoord[unit];
279    GLvector4f *normal = VB->AttribPtr[_TNL_ATTRIB_NORMAL];
280    GLfloat (*texcoord)[4] = (GLfloat (*)[4])out->start;
281    GLuint count = VB->Count;
282    GLuint i;
283    const GLfloat *norm = normal->start;
284 
285    for (i=0;i<count;i++, STRIDE_F(norm, normal->stride)) {
286       texcoord[i][0] = norm[0];
287       texcoord[i][1] = norm[1];
288       texcoord[i][2] = norm[2];
289    }
290 
291 
292    out->flags |= (in->flags & VEC_SIZE_FLAGS) | VEC_SIZE_3;
293    out->count = count;
294    out->size = MAX2(in->size, 3);
295    if (in->size == 4)
296       _mesa_copy_tab[0x8]( out, in );
297 }
298 
299 
texgen_sphere_map(struct gl_context * ctx,struct texgen_stage_data * store,GLuint unit)300 static void texgen_sphere_map( struct gl_context *ctx,
301 			       struct texgen_stage_data *store,
302 			       GLuint unit )
303 {
304    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
305    GLvector4f *in = VB->AttribPtr[VERT_ATTRIB_TEX0 + unit];
306    GLvector4f *out = &store->texcoord[unit];
307    GLfloat (*texcoord)[4] = (GLfloat (*)[4]) out->start;
308    GLuint count = VB->Count;
309    GLuint i;
310    GLfloat (*f)[3] = store->tmp_f;
311    GLfloat *m = store->tmp_m;
312 
313    (build_m_tab[VB->EyePtr->size])( store->tmp_f,
314 				    store->tmp_m,
315 				    VB->AttribPtr[_TNL_ATTRIB_NORMAL],
316 				    VB->EyePtr );
317 
318    out->size = MAX2(in->size,2);
319 
320    for (i=0;i<count;i++) {
321       texcoord[i][0] = f[i][0] * m[i] + 0.5F;
322       texcoord[i][1] = f[i][1] * m[i] + 0.5F;
323    }
324 
325    out->count = count;
326    out->flags |= (in->flags & VEC_SIZE_FLAGS) | VEC_SIZE_2;
327    if (in->size > 2)
328       _mesa_copy_tab[all_bits[in->size] & ~0x3]( out, in );
329 }
330 
331 
332 
texgen(struct gl_context * ctx,struct texgen_stage_data * store,GLuint unit)333 static void texgen( struct gl_context *ctx,
334 		    struct texgen_stage_data *store,
335 		    GLuint unit )
336 {
337    TNLcontext *tnl = TNL_CONTEXT(ctx);
338    struct vertex_buffer *VB = &tnl->vb;
339    GLvector4f *in = VB->AttribPtr[VERT_ATTRIB_TEX0 + unit];
340    GLvector4f *out = &store->texcoord[unit];
341    const struct gl_fixedfunc_texture_unit *texUnit =
342       &ctx->Texture.FixedFuncUnit[unit];
343    const GLvector4f *obj = VB->AttribPtr[_TNL_ATTRIB_POS];
344    const GLvector4f *eye = VB->EyePtr;
345    const GLvector4f *normal = VB->AttribPtr[_TNL_ATTRIB_NORMAL];
346    const GLfloat *m = store->tmp_m;
347    const GLuint count = VB->Count;
348    GLfloat (*texcoord)[4] = (GLfloat (*)[4])out->data;
349    GLfloat (*f)[3] = store->tmp_f;
350    GLuint copy;
351 
352    if (texUnit->_GenFlags & TEXGEN_NEED_M) {
353       build_m_tab[eye->size]( store->tmp_f, store->tmp_m, normal, eye );
354    } else if (texUnit->_GenFlags & TEXGEN_NEED_F) {
355       build_f_tab[eye->size]( (GLfloat *)store->tmp_f, 3, normal, eye );
356    }
357 
358 
359    out->size = MAX2(in->size, store->TexgenSize[unit]);
360    out->flags |= (in->flags & VEC_SIZE_FLAGS) | texUnit->TexGenEnabled;
361    out->count = count;
362 
363    copy = (all_bits[in->size] & ~texUnit->TexGenEnabled);
364    if (copy)
365       _mesa_copy_tab[copy]( out, in );
366 
367    if (texUnit->TexGenEnabled & S_BIT) {
368       GLuint i;
369       switch (texUnit->GenS.Mode) {
370       case GL_OBJECT_LINEAR:
371 	 _mesa_dotprod_tab[obj->size]( (GLfloat *)out->data,
372 				       sizeof(out->data[0]), obj,
373 				       texUnit->GenS.ObjectPlane );
374 	 break;
375       case GL_EYE_LINEAR:
376 	 _mesa_dotprod_tab[eye->size]( (GLfloat *)out->data,
377 				       sizeof(out->data[0]), eye,
378 				       texUnit->GenS.EyePlane );
379 	 break;
380       case GL_SPHERE_MAP:
381          for (i = 0; i < count; i++)
382             texcoord[i][0] = f[i][0] * m[i] + 0.5F;
383 	 break;
384       case GL_REFLECTION_MAP_NV:
385 	 for (i=0;i<count;i++)
386 	     texcoord[i][0] = f[i][0];
387 	 break;
388       case GL_NORMAL_MAP_NV: {
389 	 const GLfloat *norm = normal->start;
390 	 for (i=0;i<count;i++, STRIDE_F(norm, normal->stride)) {
391 	     texcoord[i][0] = norm[0];
392 	 }
393 	 break;
394       }
395       default:
396 	 _mesa_problem(ctx, "Bad S texgen");
397       }
398    }
399 
400    if (texUnit->TexGenEnabled & T_BIT) {
401       GLuint i;
402       switch (texUnit->GenT.Mode) {
403       case GL_OBJECT_LINEAR:
404 	 _mesa_dotprod_tab[obj->size]( &(out->data[0][1]),
405 				       sizeof(out->data[0]), obj,
406 				       texUnit->GenT.ObjectPlane );
407 	 break;
408       case GL_EYE_LINEAR:
409 	 _mesa_dotprod_tab[eye->size]( &(out->data[0][1]),
410 				       sizeof(out->data[0]), eye,
411 				       texUnit->GenT.EyePlane );
412 	 break;
413       case GL_SPHERE_MAP:
414          for (i = 0; i < count; i++)
415             texcoord[i][1] = f[i][1] * m[i] + 0.5F;
416 	 break;
417       case GL_REFLECTION_MAP_NV:
418 	 for (i=0;i<count;i++)
419 	     texcoord[i][1] = f[i][1];
420 	 break;
421       case GL_NORMAL_MAP_NV: {
422 	 const GLfloat *norm = normal->start;
423 	 for (i=0;i<count;i++, STRIDE_F(norm, normal->stride)) {
424 	     texcoord[i][1] = norm[1];
425 	 }
426 	 break;
427       }
428       default:
429 	 _mesa_problem(ctx, "Bad T texgen");
430       }
431    }
432 
433    if (texUnit->TexGenEnabled & R_BIT) {
434       GLuint i;
435       switch (texUnit->GenR.Mode) {
436       case GL_OBJECT_LINEAR:
437 	 _mesa_dotprod_tab[obj->size]( &(out->data[0][2]),
438 				       sizeof(out->data[0]), obj,
439 				       texUnit->GenR.ObjectPlane );
440 	 break;
441       case GL_EYE_LINEAR:
442 	 _mesa_dotprod_tab[eye->size]( &(out->data[0][2]),
443 				       sizeof(out->data[0]), eye,
444 				       texUnit->GenR.EyePlane );
445 	 break;
446       case GL_REFLECTION_MAP_NV:
447 	 for (i=0;i<count;i++)
448 	     texcoord[i][2] = f[i][2];
449 	 break;
450       case GL_NORMAL_MAP_NV: {
451 	 const GLfloat *norm = normal->start;
452 	 for (i=0;i<count;i++,STRIDE_F(norm, normal->stride)) {
453 	     texcoord[i][2] = norm[2];
454 	 }
455 	 break;
456       }
457       default:
458 	 _mesa_problem(ctx, "Bad R texgen");
459       }
460    }
461 
462    if (texUnit->TexGenEnabled & Q_BIT) {
463       switch (texUnit->GenQ.Mode) {
464       case GL_OBJECT_LINEAR:
465 	 _mesa_dotprod_tab[obj->size]( &(out->data[0][3]),
466 				       sizeof(out->data[0]), obj,
467 				       texUnit->GenQ.ObjectPlane );
468 	 break;
469       case GL_EYE_LINEAR:
470 	 _mesa_dotprod_tab[eye->size]( &(out->data[0][3]),
471 				       sizeof(out->data[0]), eye,
472 				       texUnit->GenQ.EyePlane );
473 	 break;
474       default:
475 	 _mesa_problem(ctx, "Bad Q texgen");
476       }
477    }
478 }
479 
480 
481 
482 
run_texgen_stage(struct gl_context * ctx,struct tnl_pipeline_stage * stage)483 static GLboolean run_texgen_stage( struct gl_context *ctx,
484 				   struct tnl_pipeline_stage *stage )
485 {
486    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
487    struct texgen_stage_data *store = TEXGEN_STAGE_DATA(stage);
488    GLuint i;
489 
490    if (!ctx->Texture._TexGenEnabled || ctx->VertexProgram._Current)
491       return GL_TRUE;
492 
493    for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++) {
494       struct gl_fixedfunc_texture_unit *texUnit =
495          &ctx->Texture.FixedFuncUnit[i];
496 
497       if (texUnit->TexGenEnabled) {
498 	 store->TexgenFunc[i]( ctx, store, i );
499 
500          VB->AttribPtr[VERT_ATTRIB_TEX0 + i] = &store->texcoord[i];
501       }
502    }
503 
504    return GL_TRUE;
505 }
506 
507 
validate_texgen_stage(struct gl_context * ctx,struct tnl_pipeline_stage * stage)508 static void validate_texgen_stage( struct gl_context *ctx,
509 				   struct tnl_pipeline_stage *stage )
510 {
511    struct texgen_stage_data *store = TEXGEN_STAGE_DATA(stage);
512    GLuint i;
513 
514    if (!ctx->Texture._TexGenEnabled || ctx->VertexProgram._Current)
515       return;
516 
517    for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++) {
518       struct gl_fixedfunc_texture_unit *texUnit =
519          &ctx->Texture.FixedFuncUnit[i];
520 
521       if (texUnit->TexGenEnabled) {
522 	 GLuint sz;
523 
524 	 if (texUnit->TexGenEnabled & Q_BIT)
525 	    sz = 4;
526 	 else if (texUnit->TexGenEnabled & R_BIT)
527 	    sz = 3;
528 	 else if (texUnit->TexGenEnabled & T_BIT)
529 	    sz = 2;
530 	 else
531 	    sz = 1;
532 
533 	 store->TexgenSize[i] = sz;
534 	 store->TexgenFunc[i] = texgen; /* general solution */
535 
536          /* look for special texgen cases */
537 	 if (texUnit->TexGenEnabled == (S_BIT|T_BIT|R_BIT)) {
538 	    if (texUnit->_GenFlags == TEXGEN_REFLECTION_MAP_NV) {
539 	       store->TexgenFunc[i] = texgen_reflection_map_nv;
540 	    }
541 	    else if (texUnit->_GenFlags == TEXGEN_NORMAL_MAP_NV) {
542 	       store->TexgenFunc[i] = texgen_normal_map_nv;
543 	    }
544 	 }
545 	 else if (texUnit->TexGenEnabled == (S_BIT|T_BIT) &&
546 		  texUnit->_GenFlags == TEXGEN_SPHERE_MAP) {
547 	    store->TexgenFunc[i] = texgen_sphere_map;
548 	 }
549       }
550    }
551 }
552 
553 
554 
555 
556 
557 /* Called the first time stage->run() is invoked.
558  */
alloc_texgen_data(struct gl_context * ctx,struct tnl_pipeline_stage * stage)559 static GLboolean alloc_texgen_data( struct gl_context *ctx,
560 				    struct tnl_pipeline_stage *stage )
561 {
562    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
563    struct texgen_stage_data *store;
564    GLuint i;
565 
566    stage->privatePtr = calloc(1, sizeof(*store));
567    store = TEXGEN_STAGE_DATA(stage);
568    if (!store)
569       return GL_FALSE;
570 
571    for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++)
572       _mesa_vector4f_alloc( &store->texcoord[i], 0, VB->Size, 32 );
573 
574    store->tmp_f = malloc(VB->Size * sizeof(GLfloat) * 3);
575    store->tmp_m = malloc(VB->Size * sizeof(GLfloat));
576 
577    return GL_TRUE;
578 }
579 
580 
free_texgen_data(struct tnl_pipeline_stage * stage)581 static void free_texgen_data( struct tnl_pipeline_stage *stage )
582 
583 {
584    struct texgen_stage_data *store = TEXGEN_STAGE_DATA(stage);
585    GLuint i;
586 
587    if (store) {
588       for (i = 0 ; i < MAX_TEXTURE_COORD_UNITS ; i++)
589 	 if (store->texcoord[i].data)
590 	    _mesa_vector4f_free( &store->texcoord[i] );
591 
592 
593       free( store->tmp_f );
594       free( store->tmp_m );
595       free( store );
596       stage->privatePtr = NULL;
597    }
598 }
599 
600 
601 
602 const struct tnl_pipeline_stage _tnl_texgen_stage =
603 {
604    "texgen",			/* name */
605    NULL,			/* private data */
606    alloc_texgen_data,		/* destructor */
607    free_texgen_data,		/* destructor */
608    validate_texgen_stage,		/* check */
609    run_texgen_stage		/* run -- initially set to alloc data */
610 };
611