git.mutantstargoat.com Git - dosdemo/blob - src/screen.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <assert.h>
   5 #include "screen.h"
   6 #include "demo.h"
   7
   8 struct screen *tunnel_screen(void);
   9 struct screen *fract_screen(void);
  10 struct screen *grise_screen(void);
  11 struct screen *polytest_screen(void);
  12 struct screen *plasma_screen(void);
  13
  14 #define NUM_SCR 32
  15 static struct screen *scr[NUM_SCR];
  16 static int num_screens;
  17
  18 static struct screen *cur, *prev, *next;
  19 static long trans_start, trans_dur;
  20
  21 int scr_init(void)
  22 {
  23         int i, idx = 0;
  24
  25         if(!(scr[idx++] = tunnel_screen())) {
  26                 return -1;
  27         }
  28         if(!(scr[idx++] = fract_screen())) {
  29                 return -1;
  30         }
  31         if (!(scr[idx++] = grise_screen())) {
  32                 return -1;
  33         }
  34         if(!(scr[idx++] = polytest_screen())) {
  35                 return -1;
  36         }
  37         if (!(scr[idx++] = plasma_screen())) {
  38                 return -1;
  39         }
  40         num_screens = idx;
  41
  42         assert(num_screens <= NUM_SCR);
  43
  44         for(i=0; i<num_screens; i++) {
  45                 int r;
  46                 r = scr[i]->init();
  47                 if(r == -1) {
  48                         return -1;
  49                 }
  50
  51                 /* Make the effect run first if it returns "CAFE" from ins init() */
  52                 if (r == 0xCAFE) {
  53                         struct screen *tmp;
  54                         tmp = scr[i];
  55                         scr[i] = scr[0];
  56                         scr[0] = tmp;
  57                         printf("*** Screen %s displayed out of order ***\n", scr[0]->name);
  58                 }
  59         }
  60         return 0;
  61 }
  62
  63 void scr_shutdown(void)
  64 {
  65         int i;
  66         for(i=0; i<num_screens; i++) {
  67                 scr[i]->shutdown();
  68         }
  69 }
  70
  71 void scr_update(void)
  72 {
  73         if(prev) {  /* we're in the middle of a transition */
  74                 long interval = time_msec - trans_start;
  75                 if(interval >= trans_dur) {
  76                         if(next->start) {
  77                                 next->start(trans_dur);
  78                         }
  79                         prev = 0;
  80                         cur = next;
  81                         next = 0;
  82                 }
  83         }
  84 }
  85
  86 void scr_draw(void)
  87 {
  88         if(cur) cur->draw();
  89 }
  90
  91 struct screen *scr_lookup(const char *name)
  92 {
  93         int i;
  94         for(i=0; i<num_screens; i++) {
  95                 if(strcmp(scr[i]->name, name) == 0) {
  96                         return scr[i];
  97                 }
  98         }
  99         return 0;
 100 }
 101
 102 struct screen *scr_screen(int idx)
 103 {
 104         return scr[idx];
 105 }
 106
 107 int scr_num_screens(void)
 108 {
 109         return num_screens;
 110 }
 111
 112 int scr_change(struct screen *s, long trans_time)
 113 {
 114         if(!s) return -1;
 115         if(s == cur) return 0;
 116
 117         if(trans_time) {
 118                 trans_dur = trans_time / 2; /* half for each part transition out then in */
 119                 trans_start = time_msec;
 120         } else {
 121                 trans_dur = 0;
 122         }
 123
 124         if(cur && cur->stop) {
 125                 cur->stop(trans_dur);
 126                 prev = cur;
 127                 next = s;
 128         } else {
 129                 if(s->start) {
 130                         s->start(trans_dur);
 131                 }
 132
 133                 cur = s;
 134                 prev = 0;
 135         }
 136         return 0;
 137 }