summaryrefslogtreecommitdiff
path: root/src/heretic/r_plane.c
blob: 88485620ae896a2f81923997f226779cdc912440 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 1993-2008 Raven Software
// Copyright(C) 2005-2014 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// R_planes.c

#include <stdlib.h>
#include "doomdef.h"
#include "deh_str.h"
#include "i_system.h"
#include "r_local.h"

planefunction_t floorfunc, ceilingfunc;

//
// sky mapping
//
int skyflatnum;
int skytexture;
int skytexturemid;
fixed_t skyiscale;

//
// opening
//

visplane_t visplanes[MAXVISPLANES], *lastvisplane;
visplane_t *floorplane, *ceilingplane;

short openings[MAXOPENINGS], *lastopening;

//
// clip values are the solid pixel bounding the range
// floorclip starts out SCREENHEIGHT
// ceilingclip starts out -1
//
short floorclip[SCREENWIDTH];
short ceilingclip[SCREENWIDTH];

//
// spanstart holds the start of a plane span
// initialized to 0 at start
//
int spanstart[SCREENHEIGHT];
int spanstop[SCREENHEIGHT];

//
// texture mapping
//
lighttable_t **planezlight;
fixed_t planeheight;

fixed_t yslope[SCREENHEIGHT];
fixed_t distscale[SCREENWIDTH];
fixed_t basexscale, baseyscale;

fixed_t cachedheight[SCREENHEIGHT];
fixed_t cacheddistance[SCREENHEIGHT];
fixed_t cachedxstep[SCREENHEIGHT];
fixed_t cachedystep[SCREENHEIGHT];


/*
================
=
= R_InitSkyMap
=
= Called whenever the view size changes
=
================
*/

void R_InitSkyMap(void)
{
    skyflatnum = R_FlatNumForName(DEH_String("F_SKY1"));
    skytexturemid = 200 * FRACUNIT;
    skyiscale = FRACUNIT;
}


/*
====================
=
= R_InitPlanes
=
= Only at game startup
====================
*/

void R_InitPlanes(void)
{
}


/*
================
=
= R_MapPlane
=
global vars:

planeheight
ds_source
basexscale
baseyscale
viewx
viewy

BASIC PRIMITIVE
================
*/

void R_MapPlane(int y, int x1, int x2)
{
    angle_t angle;
    fixed_t distance, length;
    unsigned index;

#ifdef RANGECHECK
    if (x2 < x1 || x1 < 0 || x2 >= viewwidth || (unsigned) y > viewheight)
        I_Error("R_MapPlane: %i, %i at %i", x1, x2, y);
#endif

    if (planeheight != cachedheight[y])
    {
        cachedheight[y] = planeheight;
        distance = cacheddistance[y] = FixedMul(planeheight, yslope[y]);

        ds_xstep = cachedxstep[y] = FixedMul(distance, basexscale);
        ds_ystep = cachedystep[y] = FixedMul(distance, baseyscale);
    }
    else
    {
        distance = cacheddistance[y];
        ds_xstep = cachedxstep[y];
        ds_ystep = cachedystep[y];
    }

    length = FixedMul(distance, distscale[x1]);
    angle = (viewangle + xtoviewangle[x1]) >> ANGLETOFINESHIFT;
    ds_xfrac = viewx + FixedMul(finecosine[angle], length);
    ds_yfrac = -viewy - FixedMul(finesine[angle], length);

    if (fixedcolormap)
        ds_colormap = fixedcolormap;
    else
    {
        index = distance >> LIGHTZSHIFT;
        if (index >= MAXLIGHTZ)
            index = MAXLIGHTZ - 1;
        ds_colormap = planezlight[index];
    }

    ds_y = y;
    ds_x1 = x1;
    ds_x2 = x2;

    spanfunc();                 // high or low detail
}

//=============================================================================

/*
====================
=
= R_ClearPlanes
=
= At begining of frame
====================
*/

void R_ClearPlanes(void)
{
    int i;
    angle_t angle;

//
// opening / clipping determination
//      
    for (i = 0; i < viewwidth; i++)
    {
        floorclip[i] = viewheight;
        ceilingclip[i] = -1;
    }

    lastvisplane = visplanes;
    lastopening = openings;

//
// texture calculation
//
    memset(cachedheight, 0, sizeof(cachedheight));
    angle = (viewangle - ANG90) >> ANGLETOFINESHIFT;    // left to right mapping

    // scale will be unit scale at SCREENWIDTH/2 distance
    basexscale = FixedDiv(finecosine[angle], centerxfrac);
    baseyscale = -FixedDiv(finesine[angle], centerxfrac);
}



/*
===============
=
= R_FindPlane
=
===============
*/

visplane_t *R_FindPlane(fixed_t height, int picnum,
                        int lightlevel, int special)
{
    visplane_t *check;

    if (picnum == skyflatnum)
    {
        // all skies map together
        height = 0;
        lightlevel = 0;
    }

    for (check = visplanes; check < lastvisplane; check++)
    {
        if (height == check->height
            && picnum == check->picnum
            && lightlevel == check->lightlevel && special == check->special)
            break;
    }

    if (check < lastvisplane)
    {
        return (check);
    }

    if (lastvisplane - visplanes == MAXVISPLANES)
    {
        I_Error("R_FindPlane: no more visplanes");
    }

    lastvisplane++;
    check->height = height;
    check->picnum = picnum;
    check->lightlevel = lightlevel;
    check->special = special;
    check->minx = SCREENWIDTH;
    check->maxx = -1;
    memset(check->top, 0xff, sizeof(check->top));
    return (check);
}

/*
===============
=
= R_CheckPlane
=
===============
*/

visplane_t *R_CheckPlane(visplane_t * pl, int start, int stop)
{
    int intrl, intrh;
    int unionl, unionh;
    int x;

    if (start < pl->minx)
    {
        intrl = pl->minx;
        unionl = start;
    }
    else
    {
        unionl = pl->minx;
        intrl = start;
    }

    if (stop > pl->maxx)
    {
        intrh = pl->maxx;
        unionh = stop;
    }
    else
    {
        unionh = pl->maxx;
        intrh = stop;
    }

    for (x = intrl; x <= intrh; x++)
        if (pl->top[x] != 0xff)
            break;

    if (x > intrh)
    {
        pl->minx = unionl;
        pl->maxx = unionh;
        return pl;              // use the same one
    }

// make a new visplane

    lastvisplane->height = pl->height;
    lastvisplane->picnum = pl->picnum;
    lastvisplane->lightlevel = pl->lightlevel;
    lastvisplane->special = pl->special;
    pl = lastvisplane++;
    pl->minx = start;
    pl->maxx = stop;
    memset(pl->top, 0xff, sizeof(pl->top));

    return pl;
}



//=============================================================================

/*
================
=
= R_MakeSpans
=
================
*/

void R_MakeSpans(int x, int t1, int b1, int t2, int b2)
{
    while (t1 < t2 && t1 <= b1)
    {
        R_MapPlane(t1, spanstart[t1], x - 1);
        t1++;
    }
    while (b1 > b2 && b1 >= t1)
    {
        R_MapPlane(b1, spanstart[b1], x - 1);
        b1--;
    }

    while (t2 < t1 && t2 <= b2)
    {
        spanstart[t2] = x;
        t2++;
    }
    while (b2 > b1 && b2 >= t2)
    {
        spanstart[b2] = x;
        b2--;
    }
}



/*
================
=
= R_DrawPlanes
=
= At the end of each frame
================
*/

void R_DrawPlanes(void)
{
    visplane_t *pl;
    int light;
    int x, stop;
    int lumpnum;
    int angle;
    byte *tempSource;

    byte *dest;
    int count;
    fixed_t frac, fracstep;

    extern byte *ylookup[MAXHEIGHT];
    extern int columnofs[MAXWIDTH];

#ifdef RANGECHECK
    if (ds_p - drawsegs > MAXDRAWSEGS)
        I_Error("R_DrawPlanes: drawsegs overflow (%i)", ds_p - drawsegs);
    if (lastvisplane - visplanes > MAXVISPLANES)
        I_Error("R_DrawPlanes: visplane overflow (%i)",
                lastvisplane - visplanes);
    if (lastopening - openings > MAXOPENINGS)
        I_Error("R_DrawPlanes: opening overflow (%i)",
                lastopening - openings);
#endif

    for (pl = visplanes; pl < lastvisplane; pl++)
    {
        if (pl->minx > pl->maxx)
            continue;
        //
        // sky flat
        //
        if (pl->picnum == skyflatnum)
        {
            dc_iscale = skyiscale;
            dc_colormap = colormaps;    // sky is allways drawn full bright
            dc_texturemid = skytexturemid;
            for (x = pl->minx; x <= pl->maxx; x++)
            {
                dc_yl = pl->top[x];
                dc_yh = pl->bottom[x];
                if (dc_yl <= dc_yh)
                {
                    angle = (viewangle + xtoviewangle[x]) >> ANGLETOSKYSHIFT;
                    dc_x = x;
                    dc_source = R_GetColumn(skytexture, angle);

                    count = dc_yh - dc_yl;
                    if (count < 0)
                        return;

#ifdef RANGECHECK
                    if ((unsigned) dc_x >= SCREENWIDTH || dc_yl < 0
                        || dc_yh >= SCREENHEIGHT)
                        I_Error("R_DrawColumn: %i to %i at %i", dc_yl, dc_yh,
                                dc_x);
#endif

                    dest = ylookup[dc_yl] + columnofs[dc_x];

                    fracstep = 1;
                    frac = (dc_texturemid >> FRACBITS) + (dc_yl - centery);
                    do
                    {
                        *dest = dc_source[frac];
                        dest += SCREENWIDTH;
                        frac += fracstep;
                    }
                    while (count--);

//                                      colfunc ();
                }
            }
            continue;
        }

        //
        // regular flat
        //
        lumpnum = firstflat + flattranslation[pl->picnum];

        tempSource = W_CacheLumpNum(lumpnum, PU_STATIC);

        switch (pl->special)
        {
            case 25:
            case 26:
            case 27:
            case 28:
            case 29:           // Scroll_North
                ds_source = tempSource;
                break;
            case 20:
            case 21:
            case 22:
            case 23:
            case 24:           // Scroll_East
                ds_source = tempSource + ((63 - ((leveltime >> 1) & 63)) <<
                                          (pl->special - 20) & 63);
                //ds_source = tempSource+((leveltime>>1)&63);
                break;
            case 30:
            case 31:
            case 32:
            case 33:
            case 34:           // Scroll_South
                ds_source = tempSource;
                break;
            case 35:
            case 36:
            case 37:
            case 38:
            case 39:           // Scroll_West
                ds_source = tempSource;
                break;
            case 4:            // Scroll_EastLavaDamage
                ds_source =
                    tempSource + (((63 - ((leveltime >> 1) & 63)) << 3) & 63);
                break;
            default:
                ds_source = tempSource;
        }
        planeheight = abs(pl->height - viewz);
        light = (pl->lightlevel >> LIGHTSEGSHIFT) + extralight;
        if (light >= LIGHTLEVELS)
            light = LIGHTLEVELS - 1;
        if (light < 0)
            light = 0;
        planezlight = zlight[light];

        pl->top[pl->maxx + 1] = 0xff;
        pl->top[pl->minx - 1] = 0xff;

        stop = pl->maxx + 1;
        for (x = pl->minx; x <= stop; x++)
            R_MakeSpans(x, pl->top[x - 1], pl->bottom[x - 1], pl->top[x],
                        pl->bottom[x]);

        W_ReleaseLumpNum(lumpnum);
    }
}