2 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
3 SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO
4 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
5 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
6 IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
7 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
8 FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
9 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
10 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
11 COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
14 * $Source: /cvs/cvsroot/d2x/texmap/ntmap.c,v $
17 * $Date: 2002-02-23 22:24:10 $
19 * Start of conversion to new texture mapper.
21 * $Log: not supported by cvs2svn $
22 * Revision 1.5 2001/10/25 09:12:16 bradleyb
23 * Completed tmap selection code.
25 * Revision 1.4 2001/10/25 02:22:46 bradleyb
26 * adding support for runtime selection of tmap funcs
28 * Revision 1.3 2001/01/31 15:18:04 bradleyb
29 * Makefile and conf.h fixes
31 * Revision 1.2 2001/01/31 14:04:46 bradleyb
32 * Fix compiler warnings
34 * Revision 1.1.1.1 2001/01/19 03:30:16 bradleyb
37 * Revision 1.4 1999/10/18 00:31:55 donut
38 * allow FP_TMAP to be used without NO_ASM
40 * Revision 1.3 1999/08/05 22:53:41 sekmu
42 * D3D patch(es) from ADB
44 * Revision 1.2 1999/07/07 21:31:09 donut
45 * removed unused vars from ntmap_scanline_lighted and slightly optomized it
47 * Revision 1.1.1.1 1999/06/14 22:14:06 donut
48 * Import of d1x 1.37 source.
50 * Revision 1.52 1995/03/14 15:13:06 john
51 * Increased MAX_Y_Pointers to 480.
53 * Revision 1.51 1995/02/23 14:25:09 john
56 * Revision 1.50 1995/02/20 18:22:58 john
57 * Put all the externs in the assembly modules into tmap_inc.asm.
58 * Also, moved all the C versions of the inner loops into a new module,
61 * Revision 1.49 1995/02/20 17:09:11 john
62 * Added code so that you can build the tmapper with no assembly!
64 * Revision 1.48 1995/01/06 11:11:30 mike
65 * even when not in editor, have 400 lines in texture map scanline table.
67 * Revision 1.47 1994/12/15 16:43:25 matt
68 * Took out code only needed by editor
70 * Revision 1.46 1994/12/09 22:35:37 mike
71 * fix bug in before call to asm_tmap_scanline_per causing write of pixel onto past right border onto left.
73 * Revision 1.45 1994/12/06 16:31:06 mike
74 * fix bug in asm_tmap_scanline_matt interface.
76 * Revision 1.44 1994/12/04 20:37:18 mike
77 * *** empty log message ***
79 * Revision 1.43 1994/12/02 23:30:04 mike
82 * Revision 1.42 1994/11/30 00:57:43 mike
85 * Revision 1.41 1994/11/28 13:34:27 mike
88 * Revision 1.40 1994/11/28 01:30:01 mike
91 * Revision 1.39 1994/11/28 01:28:59 mike
94 * Revision 1.38 1994/11/21 14:08:07 john
95 * Took out all multiple instead of divide code.
97 * Revision 1.37 1994/11/19 15:21:52 mike
98 * rip out unused code.
100 * Revision 1.36 1994/11/14 11:42:51 mike
103 * Revision 1.35 1994/11/12 16:41:36 mike
104 * *** empty log message ***
106 * Revision 1.34 1994/11/10 21:28:41 mike
107 * remove call to init_interface_vars_to_assembler.
109 * Revision 1.33 1994/11/10 11:08:59 mike
110 * detail level stuff.
112 * Revision 1.32 1994/11/09 22:55:52 matt
113 * Added variable Current_seg_depth for detail level optimization
115 * Revision 1.31 1994/11/09 19:57:31 john
116 * Added texture rle caching.
118 * Revision 1.30 1994/11/09 19:54:48 mike
119 * Call flat shader if Tmap_flat_flag set.
121 * Revision 1.29 1994/11/02 21:33:31 john
122 * Added Burger Bill's optimization, ie.. 2 muls per 8 pixels.
124 * Revision 1.28 1994/11/02 11:32:16 john
125 * Added code for c callable inner loop and code to
126 * test dividing out z0.
128 * Revision 1.27 1994/10/28 20:54:32 matt
129 * Added error checking
131 * Revision 1.26 1994/10/25 11:20:20 mike
132 * fix bug in lighting overflow checking for one scanline tall linear texture maps.
134 * Revision 1.25 1994/08/03 15:40:33 mike
135 * Prevent divide overflows, decrease occurrence of precision-caused glitches.
137 * Revision 1.24 1994/07/27 09:31:16 mike
138 * Fix concave texture map problem, decrease occurrence of unimportant int 3.
140 * Revision 1.23 1994/06/17 12:23:31 mike
141 * Support non-lighted texture maps.
143 * Revision 1.22 1994/06/11 08:10:24 mike
144 * Fix mysterious hang bug, lighting value was out of range.
146 * Revision 1.21 1994/06/09 16:10:16 mike
147 * Change SC2000 from constant to variable.
156 static char rcsid[] = "$Id: ntmap.c,v 1.6 2002-02-23 22:24:10 bradleyb Exp $";
162 #define HEADLIGHT_LIGHTING 0
165 #define PERSPECTIVE 1
177 #include "scanline.h"
179 //#include "../main/textures.h"
182 #define EDITOR_TMAP 1 //if in, include extra stuff
185 #define F15_5 (F1_0*15 + F0_5)
187 // Temporary texture map, interface from Matt's 3d system to Mike's texture mapper.
190 grs_bitmap Texmap_ptrs[NUM_TMAPS];
191 grs_bitmap Texmap4_ptrs[NUM_TMAPS];
193 fix Range_max=0; // debug, kill me
195 int Interpolation_method=0; // 0 = choose best method
196 int Lighting_on=1; // initialize to no lighting
197 int Tmap_flat_flag = 0; // 1 = render texture maps as flat shaded polygons.
198 int Current_seg_depth; // HACK INTERFACE: how far away the current segment (& thus texture) is
199 int Max_perspective_depth;
200 int Max_linear_depth;
203 extern int Window_clip_left, Window_clip_bot, Window_clip_right, Window_clip_top;
205 // These variables are the interface to assembler. They get set for each texture map, which is a real waste of time.
206 // They should be set only when they change, which is generally when the window bounds change. And, even still, it's
207 // a pretty bad interface.
208 int bytes_per_row=-1;
209 unsigned char *write_buffer;
217 #define MAX_Y_POINTERS 1024
219 int y_pointers[MAX_Y_POINTERS];
221 fix fix_recip[FIX_RECIP_TABLE_SIZE];
223 int Lighting_enabled;
224 int Fix_recip_table_computed=0;
226 fix fx_l, fx_u, fx_v, fx_z, fx_du_dx, fx_dv_dx, fx_dz_dx, fx_dl_dx;
227 int fx_xleft, fx_xright, fx_y;
228 unsigned char * pixptr;
230 int Transparency_on = 0;
231 int dither_intensity_lighting = 0;
233 ubyte * tmap_flat_cthru_table;
234 ubyte tmap_flat_color;
235 ubyte tmap_flat_shade_value;
239 // -------------------------------------------------------------------------------------
240 void init_fix_recip_table(void)
246 for (i=1; i<FIX_RECIP_TABLE_SIZE; i++)
247 fix_recip[i] = F1_0/i;
249 Fix_recip_table_computed = 1;
252 // -------------------------------------------------------------------------------------
253 // Initialize interface variables to assembler.
254 // These things used to be constants. This routine is now (10/6/93) getting called for
255 // every texture map. It should get called whenever the window changes, or, preferably,
256 // not at all. I'm pretty sure these variables are only being used for range checking.
257 void init_interface_vars_to_assembler(void)
261 bp = &grd_curcanv->cv_bitmap;
264 Assert(bp->bm_data!=NULL);
265 Assert(bp->bm_h <= MAX_Y_POINTERS);
267 // If bytes_per_row has changed, create new table of pointers.
268 if (bytes_per_row != (int) bp->bm_rowsize) {
271 bytes_per_row = (int) bp->bm_rowsize;
274 for (i=0; i<MAX_Y_POINTERS; i++) {
275 y_pointers[i] = y_val;
276 y_val += bytes_per_row;
280 write_buffer = (unsigned char *) bp->bm_data;
283 window_right = (int) bp->bm_w-1;
285 window_bottom = (int) bp->bm_h-1;
287 Window_clip_left = window_left;
288 Window_clip_right = window_right;
289 Window_clip_top = window_top;
290 Window_clip_bot = window_bottom;
292 window_width = bp->bm_w;
293 window_height = bp->bm_h;
295 if (!Fix_recip_table_computed)
296 init_fix_recip_table();
299 // -------------------------------------------------------------------------------------
301 extern g3ds_tmap Tmap1;
303 // -------------------------------------------------------------------------------------
304 // Returns number preceding val modulo modulus.
307 int prevmod(int val,int modulus)
313 // return (val + modulus - 1) % modulus;
317 // Returns number succeeding val modulo modulus.
320 int succmod(int val,int modulus)
327 // return (val + 1) % modulus;
330 // -------------------------------------------------------------------------------------
331 // Select topmost vertex (minimum y coordinate) and bottommost (maximum y coordinate) in
332 // texture map. If either is part of a horizontal edge, then select leftmost vertex for
333 // top, rightmost vertex for bottom.
334 // Important: Vertex is selected with integer precision. So, if there are vertices at
335 // (0.0,0.7) and (0.5,0.3), the first vertex is selected, because they y coordinates are
336 // considered the same, so the smaller x is favored.
338 // nv number of vertices
339 // v3d pointer to 3d vertices containing u,v,x2d,y2d coordinates
343 // -------------------------------------------------------------------------------------
344 void compute_y_bounds(g3ds_tmap *t, int *vlt, int *vlb, int *vrt, int *vrb,int *bottom_y_ind)
352 // Scan all vertices, set min_y_ind to vertex with smallest y coordinate.
353 min_y = f2i(t->verts[0].y2d);
356 min_x = f2i(t->verts[0].x2d);
359 for (i=1; i<t->nv; i++) {
360 if (f2i(t->verts[i].y2d) < min_y) {
361 min_y = f2i(t->verts[i].y2d);
363 min_x = f2i(t->verts[i].x2d);
364 } else if (f2i(t->verts[i].y2d) == min_y) {
365 if (f2i(t->verts[i].x2d) < min_x) {
367 min_x = f2i(t->verts[i].x2d);
370 if (f2i(t->verts[i].y2d) > max_y) {
371 max_y = f2i(t->verts[i].y2d);
376 //--removed mk, 11/27/94-- // Check for a non-upright-hourglass polygon and fix, if necessary, by bashing a y coordinate.
377 //--removed mk, 11/27/94-- // min_y_ind = index of minimum y coordinate, *bottom_y_ind = index of maximum y coordinate
378 //--removed mk, 11/27/94--{
379 //--removed mk, 11/27/94-- int max_temp, min_temp;
380 //--removed mk, 11/27/94--
381 //--removed mk, 11/27/94-- max_temp = *bottom_y_ind;
382 //--removed mk, 11/27/94-- if (*bottom_y_ind < min_y_ind)
383 //--removed mk, 11/27/94-- max_temp += t->nv;
384 //--removed mk, 11/27/94--
385 //--removed mk, 11/27/94-- for (i=min_y_ind; i<max_temp; i++) {
386 //--removed mk, 11/27/94-- if (f2i(t->verts[i%t->nv].y2d) > f2i(t->verts[(i+1)%t->nv].y2d)) {
387 //--removed mk, 11/27/94-- Int3();
388 //--removed mk, 11/27/94-- t->verts[(i+1)%t->nv].y2d = t->verts[i%t->nv].y2d;
389 //--removed mk, 11/27/94-- }
390 //--removed mk, 11/27/94-- }
391 //--removed mk, 11/27/94--
392 //--removed mk, 11/27/94-- min_temp = min_y_ind;
393 //--removed mk, 11/27/94-- if (min_y_ind < *bottom_y_ind)
394 //--removed mk, 11/27/94-- min_temp += t->nv;
395 //--removed mk, 11/27/94--
396 //--removed mk, 11/27/94-- for (i=*bottom_y_ind; i<min_temp; i++) {
397 //--removed mk, 11/27/94-- if (f2i(t->verts[i%t->nv].y2d) < f2i(t->verts[(i+1)%t->nv].y2d)) {
398 //--removed mk, 11/27/94-- Int3();
399 //--removed mk, 11/27/94-- t->verts[(i+1)%t->nv].y2d = t->verts[i%t->nv].y2d;
400 //--removed mk, 11/27/94-- }
401 //--removed mk, 11/27/94-- }
402 //--removed mk, 11/27/94--}
404 // Set "vertex left top", etc. based on vertex with topmost y coordinate
407 *vlb = prevmod(*vlt,t->nv);
408 *vrb = succmod(*vrt,t->nv);
410 // If right edge is horizontal, then advance along polygon bound until it no longer is or until all
411 // vertices have been examined.
412 // (Left edge cannot be horizontal, because *vlt is set to leftmost point with highest y coordinate.)
416 while (f2i(t->verts[*vrt].y2d) == f2i(t->verts[*vrb].y2d)) {
417 if (succmod(*vrt,t->nv) == original_vrt) {
420 *vrt = succmod(*vrt,t->nv);
421 *vrb = succmod(*vrt,t->nv);
425 // -------------------------------------------------------------------------------------
426 // Returns dx/dy given two vertices.
427 // If dy == 0, returns 0.0
428 // -------------------------------------------------------------------------------------
429 //--fix compute_dx_dy_lin(g3ds_tmap *t, int top_vertex,int bottom_vertex)
433 //-- // compute delta x with respect to y for any edge
434 //-- dy = f2i(t->verts[bottom_vertex].y2d - t->verts[top_vertex].y2d) + 1;
436 //-- return (t->verts[bottom_vertex].x2d - t->verts[top_vertex].x2d) / dy;
442 fix compute_du_dy_lin(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
444 return fixmul(t->verts[bottom_vertex].u - t->verts[top_vertex].u, recip_dy);
448 fix compute_dv_dy_lin(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
450 return fixmul(t->verts[bottom_vertex].v - t->verts[top_vertex].v, recip_dy);
453 fix compute_dl_dy_lin(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
455 return fixmul(t->verts[bottom_vertex].l - t->verts[top_vertex].l, recip_dy);
459 fix compute_dx_dy(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
461 return fixmul(t->verts[bottom_vertex].x2d - t->verts[top_vertex].x2d, recip_dy);
464 fix compute_du_dy(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
466 return fixmul(fixmul(t->verts[bottom_vertex].u,t->verts[bottom_vertex].z) - fixmul(t->verts[top_vertex].u,t->verts[top_vertex].z), recip_dy);
470 fix compute_dv_dy(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
472 return fixmul(fixmul(t->verts[bottom_vertex].v,t->verts[bottom_vertex].z) - fixmul(t->verts[top_vertex].v,t->verts[top_vertex].z), recip_dy);
476 fix compute_dz_dy(g3ds_tmap *t, int top_vertex,int bottom_vertex, fix recip_dy)
478 return fixmul(t->verts[bottom_vertex].z - t->verts[top_vertex].z, recip_dy);
481 int Skip_short_flag=0;
483 // -------------------------------------------------------------------------------------
484 // Texture map current scanline in perspective.
485 // -------------------------------------------------------------------------------------
486 void ntmap_scanline_lighted(grs_bitmap *srcb, int y, fix xleft, fix xright, fix uleft, fix uright, fix vleft, fix vright, fix zleft, fix zright, fix lleft, fix lright)
490 fx_xright = f2i(xright);
491 //edited 06/27/99 Matt Mueller - moved these tests up from within the switch so as not to do a bunch of needless calculations when we are just gonna return anyway. Slight fps boost?
492 if (fx_xright < Window_clip_left)
494 fx_xleft = f2i(xleft);
495 if (fx_xleft > Window_clip_right)
499 dx = fx_xright - fx_xleft;
500 if ((dx < 0) || (xright < 0) || (xleft > xright)) // the (xleft > xright) term is not redundant with (dx < 0) because dx is computed using integers
503 // setup to call assembler scanline renderer
504 if (dx < FIX_RECIP_TABLE_SIZE)
505 recip_dx = fix_recip[dx];
513 fx_du_dx = fixmul(uright - uleft,recip_dx);
514 fx_dv_dx = fixmul(vright - vleft,recip_dx);
515 fx_dz_dx = fixmul(zright - zleft,recip_dx);
517 pixptr = srcb->bm_data;
519 switch (Lighting_enabled) {
521 //added 05/17/99 Matt Mueller - prevent writing before the buffer
522 if ((fx_y == 0) && (fx_xleft < 0))
525 if (fx_xright > Window_clip_right)
526 fx_xright = Window_clip_right;
528 cur_tmap_scanline_per();
533 if (lleft < 0) lleft = 0;
534 if (lright < 0) lright = 0;
535 if (lleft > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2)) lleft = (NUM_LIGHTING_LEVELS*F1_0-F1_0/2);
536 if (lright > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2)) lright = (NUM_LIGHTING_LEVELS*F1_0-F1_0/2);
539 fx_dl_dx = fixmul(lright - lleft,recip_dx);
541 // This is a pretty ugly hack to prevent lighting overflows.
542 mul_thing = dx * fx_dl_dx;
543 if (lleft + mul_thing < 0)
545 else if (lleft + mul_thing > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2))
548 //added 05/17/99 Matt Mueller - prevent writing before the buffer
549 if ((fx_y == 0) && (fx_xleft < 0))
552 if (fx_xright > Window_clip_right)
553 fx_xright = Window_clip_right;
555 cur_tmap_scanline_per();
560 fx_xright = f2i(xright);
561 fx_xleft = f2i(xleft);
564 cur_tmap_scanline_flat();
566 Int3(); // Illegal, called an editor only routine!
573 int Do_vertical_scan=0;
577 // -------------------------------------------------------------------------------------
578 // Render a texture map with lighting using perspective interpolation in inner and outer loops.
579 // -------------------------------------------------------------------------------------
580 void ntexture_map_lighted(grs_bitmap *srcb, g3ds_tmap *t)
582 int vlt,vrt,vlb,vrb; // vertex left top, vertex right top, vertex left bottom, vertex right bottom
584 fix dx_dy_left,dx_dy_right;
585 fix du_dy_left,du_dy_right;
586 fix dv_dy_left,dv_dy_right;
587 fix dz_dy_left,dz_dy_right;
588 fix dl_dy_left,dl_dy_right;
589 fix recip_dyl, recip_dyr;
591 fix xleft,xright,uleft,vleft,uright,vright,zleft,zright,lleft,lright;
592 int next_break_left, next_break_right;
596 //remove stupid warnings in compile
604 // Determine top and bottom y coords.
605 compute_y_bounds(t,&vlt,&vlb,&vrt,&vrb,&max_y_vertex);
607 // Set top and bottom (of entire texture map) y coordinates.
608 topy = f2i(v3d[vlt].y2d);
609 boty = f2i(v3d[max_y_vertex].y2d);
610 if (topy > Window_clip_bot)
612 if (boty > Window_clip_bot)
613 boty = Window_clip_bot;
615 // Set amount to change x coordinate for each advance to next scanline.
616 dy = f2i(t->verts[vlb].y2d) - f2i(t->verts[vlt].y2d);
617 if (dy < FIX_RECIP_TABLE_SIZE)
618 recip_dyl = fix_recip[dy];
622 dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dyl);
623 du_dy_left = compute_du_dy(t,vlt,vlb, recip_dyl);
624 dv_dy_left = compute_dv_dy(t,vlt,vlb, recip_dyl);
625 dz_dy_left = compute_dz_dy(t,vlt,vlb, recip_dyl);
627 dy = f2i(t->verts[vrb].y2d) - f2i(t->verts[vrt].y2d);
628 if (dy < FIX_RECIP_TABLE_SIZE)
629 recip_dyr = fix_recip[dy];
633 du_dy_right = compute_du_dy(t,vrt,vrb, recip_dyr);
634 dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dyr);
635 dv_dy_right = compute_dv_dy(t,vrt,vrb, recip_dyr);
636 dz_dy_right = compute_dz_dy(t,vrt,vrb, recip_dyr);
638 if (Lighting_enabled) {
639 dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dyl);
640 dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dyr);
646 // Set initial values for x, u, v
647 xleft = v3d[vlt].x2d;
648 xright = v3d[vrt].x2d;
653 uleft = fixmul(v3d[vlt].u,zleft);
654 uright = fixmul(v3d[vrt].u,zright);
655 vleft = fixmul(v3d[vlt].v,zleft);
656 vright = fixmul(v3d[vrt].v,zright);
658 // scan all rows in texture map from top through first break.
659 next_break_left = f2i(v3d[vlb].y2d);
660 next_break_right = f2i(v3d[vrb].y2d);
662 for (y = topy; y < boty; y++) {
664 // See if we have reached the end of the current left edge, and if so, set
665 // new values for dx_dy and x,u,v
666 if (y == next_break_left) {
669 // Handle problem of double points. Search until y coord is different. Cannot get
670 // hung in an infinite loop because we know there is a vertex with a lower y coordinate
671 // because in the for loop, we don't scan all spanlines.
672 while (y == f2i(v3d[vlb].y2d)) {
674 vlb = prevmod(vlb,t->nv);
676 next_break_left = f2i(v3d[vlb].y2d);
678 dy = f2i(t->verts[vlb].y2d) - f2i(t->verts[vlt].y2d);
679 if (dy < FIX_RECIP_TABLE_SIZE)
680 recip_dy = fix_recip[dy];
684 dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dy);
686 xleft = v3d[vlt].x2d;
688 uleft = fixmul(v3d[vlt].u,zleft);
689 vleft = fixmul(v3d[vlt].v,zleft);
692 du_dy_left = compute_du_dy(t,vlt,vlb, recip_dy);
693 dv_dy_left = compute_dv_dy(t,vlt,vlb, recip_dy);
694 dz_dy_left = compute_dz_dy(t,vlt,vlb, recip_dy);
696 if (Lighting_enabled) {
697 dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dy);
702 // See if we have reached the end of the current left edge, and if so, set
703 // new values for dx_dy and x. Not necessary to set new values for u,v.
704 if (y == next_break_right) {
707 while (y == f2i(v3d[vrb].y2d)) {
709 vrb = succmod(vrb,t->nv);
712 next_break_right = f2i(v3d[vrb].y2d);
714 dy = f2i(t->verts[vrb].y2d) - f2i(t->verts[vrt].y2d);
715 if (dy < FIX_RECIP_TABLE_SIZE)
716 recip_dy = fix_recip[dy];
720 dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dy);
722 xright = v3d[vrt].x2d;
724 uright = fixmul(v3d[vrt].u,zright);
725 vright = fixmul(v3d[vrt].v,zright);
727 du_dy_right = compute_du_dy(t,vrt,vrb, recip_dy);
728 dv_dy_right = compute_dv_dy(t,vrt,vrb, recip_dy);
729 dz_dy_right = compute_dz_dy(t,vrt,vrb, recip_dy);
731 if (Lighting_enabled) {
732 dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dy);
737 if (Lighting_enabled) {
738 if (y >= Window_clip_top)
739 ntmap_scanline_lighted(srcb,y,xleft,xright,uleft,uright,vleft,vright,zleft,zright,lleft,lright);
741 lright += dl_dy_right;
743 if (y >= Window_clip_top)
744 ntmap_scanline_lighted(srcb,y,xleft,xright,uleft,uright,vleft,vright,zleft,zright,lleft,lright);
749 uright += du_dy_right;
750 vright += dv_dy_right;
753 xright += dx_dy_right;
756 zright += dz_dy_right;
760 // We can get lleft or lright out of bounds here because we compute dl_dy using fixed point values,
761 // but we plot an integer number of scanlines, therefore doing an integer number of additions of the delta.
764 // mprintf(0, "[%i %i %i] ", y, f2i(xleft), f2i(xright));
766 ntmap_scanline_lighted(srcb,y,xleft,xright,uleft,uright,vleft,vright,zleft,zright,lleft,lright);
770 // -------------------------------------------------------------------------------------
771 // Texture map current scanline using linear interpolation.
772 // -------------------------------------------------------------------------------------
773 void ntmap_scanline_lighted_linear(grs_bitmap *srcb, int y, fix xleft, fix xright, fix uleft, fix uright, fix vleft, fix vright, fix lleft, fix lright)
778 fix du_dx,dv_dx,dl_dx;
784 dx = f2i(xright) - f2i(xleft);
785 if ((dx < 0) || (xright < 0) || (xleft > xright)) // the (xleft > xright) term is not redundant with (dx < 0) because dx is computed using integers
788 // setup to call assembler scanline renderer
789 if (dx < FIX_RECIP_TABLE_SIZE)
790 recip_dx = fix_recip[dx];
794 du_dx = fixmul(uright - uleft,recip_dx);
795 dv_dx = fixmul(vright - vleft,recip_dx);
802 fx_xright = f2i(xright);
803 fx_xleft = f2i(xleft);
804 pixptr = srcb->bm_data;
806 switch (Lighting_enabled) {
808 //added 07/11/99 adb - prevent writing before the buffer
813 cur_tmap_scanline_lin_nolight();
821 if (lleft > MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS)
822 lleft = MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS;
823 if (lright > MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS)
824 lright = MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS;
826 //added 07/11/99 adb - prevent writing before the buffer
835 fx_dl_dx = fixmul(lright - lleft,recip_dx);
837 // This is a pretty ugly hack to prevent lighting overflows.
838 mul_thing = dx * fx_dl_dx;
839 if (lleft + mul_thing < 0)
841 else if (lleft + mul_thing > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2))
846 dl_dx = fixmul(lright - lleft,recip_dx);
848 cur_tmap_scanline_lin();
852 fx_xright = f2i(xright);
853 fx_xleft = f2i(xleft);
855 cur_tmap_scanline_flat();
857 Int3(); // Illegal, called an editor only routine!
863 // -------------------------------------------------------------------------------------
864 // Render a texture map with lighting using perspective interpolation in inner and outer loops.
865 // -------------------------------------------------------------------------------------
866 void ntexture_map_lighted_linear(grs_bitmap *srcb, g3ds_tmap *t)
868 int vlt,vrt,vlb,vrb; // vertex left top, vertex right top, vertex left bottom, vertex right bottom
870 fix dx_dy_left,dx_dy_right;
871 fix du_dy_left,du_dy_right;
872 fix dv_dy_left,dv_dy_right;
873 fix dl_dy_left,dl_dy_right;
875 fix xleft,xright,uleft,vleft,uright,vright,lleft,lright;
876 int next_break_left, next_break_right;
877 fix recip_dyl, recip_dyr;
881 //remove stupid warnings in compile
889 // Determine top and bottom y coords.
890 compute_y_bounds(t,&vlt,&vlb,&vrt,&vrb,&max_y_vertex);
892 // Set top and bottom (of entire texture map) y coordinates.
893 topy = f2i(v3d[vlt].y2d);
894 boty = f2i(v3d[max_y_vertex].y2d);
896 if (topy > Window_clip_bot)
898 if (boty > Window_clip_bot)
899 boty = Window_clip_bot;
901 dy = f2i(t->verts[vlb].y2d) - f2i(t->verts[vlt].y2d);
902 if (dy < FIX_RECIP_TABLE_SIZE)
903 recip_dyl = fix_recip[dy];
907 dy = f2i(t->verts[vrb].y2d) - f2i(t->verts[vrt].y2d);
908 if (dy < FIX_RECIP_TABLE_SIZE)
909 recip_dyr = fix_recip[dy];
913 // Set amount to change x coordinate for each advance to next scanline.
914 dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dyl);
915 dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dyr);
917 du_dy_left = compute_du_dy_lin(t,vlt,vlb, recip_dyl);
918 du_dy_right = compute_du_dy_lin(t,vrt,vrb, recip_dyr);
920 dv_dy_left = compute_dv_dy_lin(t,vlt,vlb, recip_dyl);
921 dv_dy_right = compute_dv_dy_lin(t,vrt,vrb, recip_dyr);
923 if (Lighting_enabled) {
924 dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dyl);
925 dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dyr);
931 // Set initial values for x, u, v
932 xleft = v3d[vlt].x2d;
933 xright = v3d[vrt].x2d;
940 // scan all rows in texture map from top through first break.
941 next_break_left = f2i(v3d[vlb].y2d);
942 next_break_right = f2i(v3d[vrb].y2d);
944 for (y = topy; y < boty; y++) {
946 // See if we have reached the end of the current left edge, and if so, set
947 // new values for dx_dy and x,u,v
948 if (y == next_break_left) {
951 // Handle problem of double points. Search until y coord is different. Cannot get
952 // hung in an infinite loop because we know there is a vertex with a lower y coordinate
953 // because in the for loop, we don't scan all spanlines.
954 while (y == f2i(v3d[vlb].y2d)) {
956 vlb = prevmod(vlb,t->nv);
958 next_break_left = f2i(v3d[vlb].y2d);
960 dy = f2i(t->verts[vlb].y2d) - f2i(t->verts[vlt].y2d);
961 if (dy < FIX_RECIP_TABLE_SIZE)
962 recip_dy = fix_recip[dy];
966 dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dy);
968 xleft = v3d[vlt].x2d;
973 du_dy_left = compute_du_dy_lin(t,vlt,vlb, recip_dy);
974 dv_dy_left = compute_dv_dy_lin(t,vlt,vlb, recip_dy);
976 if (Lighting_enabled) {
977 dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dy);
982 // See if we have reached the end of the current left edge, and if so, set
983 // new values for dx_dy and x. Not necessary to set new values for u,v.
984 if (y == next_break_right) {
987 while (y == f2i(v3d[vrb].y2d)) {
989 vrb = succmod(vrb,t->nv);
992 dy = f2i(t->verts[vrb].y2d) - f2i(t->verts[vrt].y2d);
993 if (dy < FIX_RECIP_TABLE_SIZE)
994 recip_dy = fix_recip[dy];
998 next_break_right = f2i(v3d[vrb].y2d);
999 dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dy);
1001 xright = v3d[vrt].x2d;
1002 uright = v3d[vrt].u;
1003 vright = v3d[vrt].v;
1005 du_dy_right = compute_du_dy_lin(t,vrt,vrb, recip_dy);
1006 dv_dy_right = compute_dv_dy_lin(t,vrt,vrb, recip_dy);
1008 if (Lighting_enabled) {
1009 dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dy);
1010 lright = v3d[vrt].l;
1014 if (Lighting_enabled) {
1015 ntmap_scanline_lighted_linear(srcb,y,xleft,xright,uleft,uright,vleft,vright,lleft,lright);
1016 lleft += dl_dy_left;
1017 lright += dl_dy_right;
1019 ntmap_scanline_lighted_linear(srcb,y,xleft,xright,uleft,uright,vleft,vright,lleft,lright);
1021 uleft += du_dy_left;
1022 vleft += dv_dy_left;
1024 uright += du_dy_right;
1025 vright += dv_dy_right;
1027 xleft += dx_dy_left;
1028 xright += dx_dy_right;
1032 // We can get lleft or lright out of bounds here because we compute dl_dy using fixed point values,
1033 // but we plot an integer number of scanlines, therefore doing an integer number of additions of the delta.
1035 ntmap_scanline_lighted_linear(srcb,y,xleft,xright,uleft,uright,vleft,vright,lleft,lright);
1038 // fix DivNum = F1_0*12;
1040 extern void draw_tmap_flat(grs_bitmap *bp,int nverts,g3s_point **vertbuf);
1042 // -------------------------------------------------------------------------------------
1043 // Interface from Matt's data structures to Mike's texture mapper.
1044 // -------------------------------------------------------------------------------------
1045 void draw_tmap(grs_bitmap *bp,int nverts,g3s_point **vertbuf)
1049 // These variables are used in system which renders texture maps which lie on one scanline as a line.
1050 // fix div_numerator;
1051 int lighting_on_save = Lighting_on;
1053 Assert(nverts <= MAX_TMAP_VERTS);
1056 #ifdef USE_MULT_CODE
1057 if ( !divide_table_filled ) fill_divide_table();
1060 // -- now called from g3_start_frame -- init_interface_vars_to_assembler();
1062 // If no transparency and seg depth is large, render as flat shaded.
1063 if ((Current_seg_depth > Max_linear_depth) && ((bp->bm_flags & 3) == 0)) {
1064 draw_tmap_flat(bp, nverts, vertbuf);
1068 if ( bp->bm_flags & BM_FLAG_RLE )
1069 bp = rle_expand_texture( bp ); // Expand if rle'd
1071 Transparency_on = bp->bm_flags & BM_FLAG_TRANSPARENT;
1072 if (bp->bm_flags & BM_FLAG_NO_LIGHTING)
1076 // Setup texture map in Tmap1
1077 Tmap1.nv = nverts; // Initialize number of vertices
1079 // div_numerator = DivNum; //f1_0*3;
1081 for (i=0; i<nverts; i++) {
1082 g3ds_vertex *tvp = &Tmap1.verts[i];
1083 g3s_point *vp = vertbuf[i];
1085 tvp->x2d = vp->p3_sx;
1086 tvp->y2d = vp->p3_sy;
1088 // Check for overflow on fixdiv. Will overflow on vp->z <= something small. Allow only as low as 256.
1089 if (vp->p3_z < 256) {
1091 // Int3(); // we would overflow if we divided!
1094 tvp->z = fixdiv(F1_0*12, vp->p3_z);
1095 tvp->u = vp->p3_u << 6; //* bp->bm_w;
1096 tvp->v = vp->p3_v << 6; //* bp->bm_h;
1098 Assert(Lighting_on < 3);
1101 tvp->l = vp->p3_l * NUM_LIGHTING_LEVELS;
1105 Lighting_enabled = Lighting_on;
1107 // Now, call my texture mapper.
1109 switch (Interpolation_method) { // 0 = choose, 1 = linear, 2 = /8 perspective, 3 = full perspective
1110 case 0: // choose best interpolation
1112 if (Current_seg_depth > Max_perspective_depth)
1113 ntexture_map_lighted_linear(bp, &Tmap1);
1115 ntexture_map_lighted(bp, &Tmap1);
1117 case 1: // linear interpolation
1119 ntexture_map_lighted_linear(bp, &Tmap1);
1121 case 2: // perspective every 8th pixel interpolation
1123 ntexture_map_lighted(bp, &Tmap1);
1125 case 3: // perspective every pixel interpolation
1126 per2_flag = 0; // this hack means do divide every pixel
1127 ntexture_map_lighted(bp, &Tmap1);
1130 Assert(0); // Illegal value for Interpolation_method, must be 0,1,2,3
1133 switch (Interpolation_method) { // 0 = choose, 1 = linear, 2 = /8 perspective, 3 = full perspective
1134 case 0: // choose best interpolation
1136 if (Current_seg_depth > Max_perspective_depth)
1137 ntexture_map_lighted_linear(bp, &Tmap1);
1139 ntexture_map_lighted(bp, &Tmap1);
1141 case 1: // linear interpolation
1143 ntexture_map_lighted_linear(bp, &Tmap1);
1145 case 2: // perspective every 8th pixel interpolation
1147 ntexture_map_lighted(bp, &Tmap1);
1149 case 3: // perspective every pixel interpolation
1150 per2_flag = 0; // this hack means do divide every pixel
1151 ntexture_map_lighted(bp, &Tmap1);
1154 Assert(0); // Illegal value for Interpolation_method, must be 0,1,2,3
1158 Lighting_on = lighting_on_save;