1 /*
2 
3 Copyright (C) 2015-2018 Night Dive Studios, LLC.
4 
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
9 
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 GNU General Public License for more details.
14 
15 You should have received a copy of the GNU General Public License
16 along with this program.  If not, see <http://www.gnu.org/licenses/>.
17 
18 */
19 /*
20  * $Source: r:/prj/lib/src/2d/RCS/genlf.c $
21  * $Revision: 1.3 $
22  * $Author: kevin $
23  * $Date: 1994/08/16 12:50:14 $
24  *
25  * Routines to floor texture map a flat8 bitmap to a generic canvas.
26  *
27  * This file is part of the 2d library.
28  *
29  */
30 
31 #include "cnvdat.h"
32 #include "fl8tf.h"
33 #include "fl8tmapdv.h"
34 #include "gente.h"
35 #include "poly.h"
36 #include "scrmac.h"
37 #include "tmapint.h"
38 #include "vtab.h"
39 
40 int gri_lit_floor_umap_loop(grs_tmap_loop_info *tli);
41 
gri_lit_floor_umap_loop(grs_tmap_loop_info * tli)42 int gri_lit_floor_umap_loop(grs_tmap_loop_info *tli) {
43 
44 #if InvDiv
45     fix inv = fix_div(fix_make(1, 0), tli->w);
46     fix u = fix_mul_asm_safe(tli->left.u, inv);
47     fix du = fix_mul_asm_safe(tli->right.u, inv) - u;
48     fix v = fix_mul_asm_safe(tli->left.v, inv);
49     fix dv = fix_mul_asm_safe(tli->right.v, inv) - v;
50     fix i = fix_mul_asm_safe(tli->left.i, inv);
51     fix di = fix_mul_asm_safe(tli->right.i, inv) - i;
52 #else
53     fix u = fix_div(tli->left.u, tli->w);
54     fix du = fix_div(tli->right.u, tli->w) - u;
55     fix v = fix_div(tli->left.v, tli->w);
56     fix dv = fix_div(tli->right.v, tli->w) - v;
57     fix i = fix_div(tli->left.i, tli->w);
58     fix di = fix_div(tli->right.i, tli->w) - i;
59 #endif
60 
61     ulong t_mask = tli->mask;
62     uchar t_wlog = tli->bm.wlog;
63     uchar *g_ltab = grd_screen->ltab;
64     int32_t *t_vtab = tli->vtab;
65     uchar *t_bits = tli->bm.bits;
66 
67     do {
68         fix dx = tli->right.x - tli->left.x;
69         if (dx > 0)
70         {
71 
72 #if InvDiv
73             inv = fix_div(fix_make(1, 0) << 8, dx);
74             di = fix_mul_asm_safe_light(di, inv);
75             inv >>= 8;
76             du = fix_mul_asm_safe(du, inv);
77             dv = fix_mul_asm_safe(dv, inv);
78 #else
79             du = fix_div(du, dx);
80             dv = fix_div(dv, dx);
81             di = fix_div(di, dx);
82 #endif
83 
84             fix d = fix_ceil(tli->left.x) - tli->left.x;
85             u += fix_mul(du, d);
86             v += fix_mul(dv, d);
87             i += fix_mul(di, d);
88 
89             uchar *p_dest = grd_bm.bits + (grd_bm.row * tli->y) + fix_cint(tli->left.x);
90 
91             int x = fix_cint(tli->right.x) - fix_cint(tli->left.x);
92 
93             switch (tli->bm.hlog) {
94                 case GRL_OPAQUE:
95                     for (; x > 0; x--) {
96                         int k = t_vtab[fix_fint(v)] + fix_fint(u);
97                         *(p_dest++) = g_ltab[t_bits[k] + fix_light(i)];
98                         // gr_fill_upixel(g_ltab[t_bits[k]+fix_light(i)],x,t_y);
99                     }
100                 break;
101 
102                 case GRL_TRANS:
103                     for (; x > 0; x--) {
104                         int k = t_vtab[fix_fint(v)] + fix_fint(u);
105                         k = t_bits[k];
106                         if (k != 0) *p_dest = g_ltab[k + fix_light(i)];
107                         // gr_fill_upixel(g_ltab[k+fix_light(i)],x,t_y);
108                         p_dest++;
109                         u += du;
110                         v += dv;
111                         i += di;
112                     }
113                 break;
114 
115                 case GRL_OPAQUE|GRL_LOG2:
116                     for (; x > 0; x--) {
117                         int k = ((fix_fint(v)<<t_wlog)+fix_fint(u))&t_mask;
118                         *(p_dest++) = g_ltab[t_bits[k]+fix_light(i)];
119                         // gr_fill_upixel(g_ltab[t_bits[k]+fix_light(i)],x,t_y);
120                         u += du;
121                         v += dv;
122                         i += di;
123                     }
124                 break;
125 
126                 case GRL_TRANS | GRL_LOG2:
127                     for (; x > 0; x--) {
128                         int k = ((fix_fint(v) << t_wlog) + fix_fint(u)) & t_mask;
129                         k = t_bits[k];
130                         if (k != 0) *p_dest = g_ltab[k + fix_light(i)];
131                         // gr_fill_upixel(g_ltab[k+fix_light(i)],x,t_y);
132                         p_dest++;
133                         u += du;
134                         v += dv;
135                         i += di;
136                     }
137                 break;
138             }
139         }
140 
141         tli->w += tli->dw;
142 
143 #if InvDiv
144         inv = fix_div(fix_make(1, 0), tli->w);
145         u = fix_mul_asm_safe((tli->left.u += tli->left.du), inv);
146         tli->right.u += tli->right.du;
147         du = fix_mul_asm_safe(tli->right.u, inv) - u;
148         v = fix_mul_asm_safe((tli->left.v += tli->left.dv), inv);
149         tli->right.v += tli->right.dv;
150         dv = fix_mul_asm_safe(tli->right.v, inv) - v;
151         i = fix_mul_asm_safe((tli->left.i += tli->left.di), inv);
152         tli->right.i += tli->right.di;
153         di = fix_mul_asm_safe(tli->right.i, inv) - i;
154 #else
155         u = fix_div((tli->left.u += tli->left.du), tli->w);
156         tli->right.u += tli->right.du;
157         du = fix_div(tli->right.u, tli->w) - u;
158         v = fix_div((tli->left.v += tli->left.dv), tli->w);
159         tli->right.v += tli->right.dv;
160         dv = fix_div(tli->right.v, tli->w) - v;
161         i = fix_div((tli->left.i += tli->left.di), tli->w);
162         tli->right.i += tli->right.di;
163         di = fix_div(tli->right.i, tli->w) - i;
164 #endif
165 
166         tli->left.x += tli->left.dx;
167         tli->right.x += tli->right.dx;
168 
169         tli->y++;
170 
171     } while (--(tli->n) > 0);
172 
173     return FALSE; // tmap OK
174 }
175 
gri_trans_lit_floor_umap_init(grs_tmap_loop_info * tli)176 void gri_trans_lit_floor_umap_init(grs_tmap_loop_info *tli) {
177     if ((tli->bm.row == (1 << tli->bm.wlog)) && (tli->bm.h == (1 << tli->bm.hlog))) {
178         tli->mask = (1 << (tli->bm.hlog + tli->bm.wlog)) - 1;
179         tli->bm.hlog = GRL_TRANS | GRL_LOG2;
180     } else {
181         tli->vtab = gr_make_vtab(&(tli->bm));
182         tli->bm.hlog = GRL_TRANS;
183     }
184     tli->loop_func = (void (*)())gri_lit_floor_umap_loop;
185     tli->left_edge_func = (void (*)())gri_uviwx_edge;
186     tli->right_edge_func = (void (*)())gri_uviwx_edge;
187 }
188 
gri_opaque_lit_floor_umap_init(grs_tmap_loop_info * tli)189 void gri_opaque_lit_floor_umap_init(grs_tmap_loop_info *tli) {
190     if ((tli->bm.row == (1 << tli->bm.wlog)) && (tli->bm.h == (1 << tli->bm.hlog))) {
191         tli->mask = (1 << (tli->bm.hlog + tli->bm.wlog)) - 1;
192         tli->bm.hlog = GRL_OPAQUE | GRL_LOG2;
193     } else {
194         tli->vtab = gr_make_vtab(&(tli->bm));
195         tli->bm.hlog = GRL_OPAQUE;
196     }
197     tli->loop_func = (void (*)())gri_lit_floor_umap_loop;
198     tli->left_edge_func = (void (*)())gri_uviwx_edge;
199     tli->right_edge_func = (void (*)())gri_uviwx_edge;
200 }
201