git.mutantstargoat.com Git - retrocrawl/blob - src/sprite.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include "sprite.h"
   4 #include "hwregs.h"
   5 #include "copper.h"
   6
   7 #define MAX_SPRITES     32
   8
   9 static int scount;
  10 static struct sprite *spr[MAX_SPRITES];
  11 static struct sprite *hwspr[4]; /* 4 channels because we support only attached sprites */
  12
  13 static uint16_t nullspr[] = {
  14         0x2000, 0x2100,
  15         0x0000, 0x0000,
  16         0x0000, 0x0000
  17 };
  18 static uint32_t nullspr_addr = (intptr_t)nullspr;
  19
  20 static uint32_t *coplist;
  21
  22
  23 void begin_sprites(void)
  24 {
  25         scount = 0;
  26         memset(hwspr, 0, sizeof hwspr);
  27
  28         coplist = copperlist_end;
  29 }
  30
  31 void end_sprites(void)
  32 {
  33         int i, j, reg;
  34
  35         copperlist_end = coplist;
  36
  37         /* initially point all sprites to the null sprite */
  38         reg = REGN_SPR0PTH;
  39         for(i=0; i<8; i++) {
  40                 add_copper(COPPER_MOVE(reg, nullspr_addr >> 16));
  41                 add_copper(COPPER_MOVE(reg + 2, nullspr_addr));
  42                 reg += 4;
  43         }
  44
  45 #if 0
  46         /* sort sprites by increasing start position */
  47         for(i=0; i<scount; i++) {
  48                 for(j=i+1; j<scount; j++) {
  49                         if(spr[j]->y < spr[i]->y) {
  50                                 struct sprite *tmp = spr[i];
  51                                 spr[i] = spr[j];
  52                                 spr[j] = tmp;
  53                         }
  54                 }
  55         }
  56 #endif
  57
  58         /* set sprite positions and populate copperlist to draw
  59          * hardware sprites
  60          */
  61         for(i=0; i<scount; i++) {
  62                 struct sprite *s = spr[i];
  63                 uint16_t sx = 0x80 + s->x;
  64                 uint16_t sy = 0x2c + s->y;
  65                 uint16_t vstop = sy + s->height;
  66                 uint32_t addr;
  67                 int reuse = 0;
  68
  69                 int chan[4];
  70                 int nchan_found = 0;
  71                 for(j=0; j<4; j++) {
  72                         if(!hwspr[j] || hwspr[j]->y + hwspr[j]->height < s->y) {
  73                                 if(hwspr[j]) {
  74                                         reuse = 1;
  75                                 }
  76                                 chan[nchan_found++] = j;
  77                                 hwspr[j] = s;
  78                                 if(nchan_found >= s->hwslices) {
  79                                         break;
  80                                 }
  81                         }
  82                 }
  83                 if(nchan_found < s->hwslices) continue;
  84
  85 //              if(reuse) {
  86                         printf("copper wait: %d\n", (int)s->y - 1);
  87                         add_copper(COPPER_VWAIT(s->y - 1));
  88 //              }
  89
  90                 for(j=0; j<s->hwslices; j++) {
  91                         int idx = chan[j] * 2;
  92                         reg = REGN_SPR0PTH + idx * 4;
  93
  94                         s->hwspr[idx][0] = s->hwspr[idx + 1][0] = (sx >> 1) | (sy << 8);
  95                         s->hwspr[idx][1] = s->hwspr[idx + 1][1] = (vstop << 8) |
  96                                 ((vstop >> 7) & 2) | (sx & 1) | 0x80;
  97
  98                         addr = (intptr_t)s->hwspr[idx];
  99                         add_copper(COPPER_MOVE(reg, addr >> 16));
 100                         add_copper(COPPER_MOVE(reg + 2, addr));
 101                         reg += 4;
 102                         addr = (intptr_t)s->hwspr[idx + 1];
 103                         add_copper(COPPER_MOVE(reg, addr >> 16));
 104                         add_copper(COPPER_MOVE(reg + 2, addr));
 105
 106                         sx += 16;
 107                 }
 108         }
 109
 110         *copperlist_end = COPPER_END;
 111         copperlist_end = coplist;
 112 }
 113
 114 void draw_sprite(struct sprite *s, int x, int y)
 115 {
 116         if(s->img) {
 117                 /* blitter sprite */
 118         } else {
 119                 /* hw sprites */
 120                 spr[scount++] = s;
 121                 s->x = x - s->origx;
 122                 s->y = y - s->origy;
 123         }
 124 }