change parts with number keys

[dosdemo] / src / screen.c

diff --git a/src/screen.c b/src/screen.c
index a0faa4b..2387d52 100644 (file)
--- a/src/screen.c
+++ b/src/screen.c
@@ -1,26 +1,35 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <assert.h>
 #include "screen.h"
 #include "demo.h"
 
 struct screen *tunnel_screen(void);
+struct screen *fract_screen(void);
 
-#define NUM_SCR        1
+#define NUM_SCR        32
 static struct screen *scr[NUM_SCR];
+static int num_screens;
 
 static struct screen *cur, *prev, *next;
 static long trans_start, trans_dur;
 
 int scr_init(void)
 {
-       int i;
+       int i, idx = 0;
 
-       if(!(scr[0] = tunnel_screen())) {
+       if(!(scr[idx++] = tunnel_screen())) {
+               return -1;
+       }
+       if(!(scr[idx++] = fract_screen())) {
                return -1;
        }
+       num_screens = idx;
 
-       for(i=0; i<NUM_SCR; i++) {
+       assert(num_screens <= NUM_SCR);
+
+       for(i=0; i<num_screens; i++) {
                if(scr[i]->init() == -1) {
                        return -1;
                }
@@ -31,7 +40,7 @@ int scr_init(void)
 void scr_shutdown(void)
 {
        int i;
-       for(i=0; i<NUM_SCR; i++) {
+       for(i=0; i<num_screens; i++) {
                scr[i]->shutdown();
        }
 }
@@ -41,7 +50,9 @@ void scr_update(void)
        if(prev) {      /* we're in the middle of a transition */
                long interval = time_msec - trans_start;
                if(interval >= trans_dur) {
-                       next->start(trans_dur);
+                       if(next->start) {
+                               next->start(trans_dur);
+                       }
                        prev = 0;
                        cur = next;
                        next = 0;
@@ -57,7 +68,7 @@ void scr_draw(void)
 struct screen *scr_lookup(const char *name)
 {
        int i;
-       for(i=0; i<NUM_SCR; i++) {
+       for(i=0; i<num_screens; i++) {
                if(strcmp(scr[i]->name, name) == 0) {
                        return scr[i];
                }
@@ -65,6 +76,16 @@ struct screen *scr_lookup(const char *name)
        return 0;
 }
 
+struct screen *scr_screen(int idx)
+{
+       return scr[idx];
+}
+
+int scr_num_screens(void)
+{
+       return num_screens;
+}
+
 int scr_change(struct screen *s, long trans_time)
 {
        if(!s) return -1;
@@ -78,12 +99,16 @@ int scr_change(struct screen *s, long trans_time)
        }
 
        if(cur) {
-               cur->stop(trans_dur);
+               if(cur->stop) {
+                       cur->stop(trans_dur);
+               }
 
                prev = cur;
                next = s;
        } else {
-               s->start(trans_dur);
+               if(s->start) {
+                       s->start(trans_dur);
+               }
 
                cur = s;
                prev = 0;