zoo demo: smooth out delays in mselect input #835

src/demo/zoo.c

@@ -57,7 +57,7 @@ static struct ncmselector_item mselect_items[] = {
 
 static struct ncmultiselector*
 multiselector_demo(struct ncplane* n, struct ncplane* under, int dimx,
-                   int y, pthread_mutex_t* lock, int* res){
+                   int y, pthread_mutex_t* lock, int* ret){
   struct notcurses* nc = ncplane_notcurses(n);
   ncmultiselector_options mopts = {
     .maxdisplay = 8,
@@ -89,20 +89,38 @@ multiselector_demo(struct ncplane* n, struct ncplane* under, int dimx,
   pthread_mutex_unlock(lock);
   ncinput ni;
   for(int i = -length + 1 ; i < dimx - (length + 1) ; ++i){
-    if( (*res = locked_demo_render(nc, lock)) ){
-      ncmultiselector_destroy(mselector);
-      return NULL;
-    }
-    ncplane_move_yx(mplane, y, i);
-    char32_t wc = demo_getc(nc, &swoopdelay, &ni);
-    if(wc == (char32_t)-1){
-      ncmultiselector_destroy(mselector);
-      return NULL;
-    }else if(wc){
-      ncmultiselector_offer_input(mselector, &ni);
-    }
+    struct timespec now, deadline;
+    clock_gettime(CLOCK_MONOTONIC, &now);
+    ns_to_timespec(timespec_to_ns(&swoopdelay) + timespec_to_ns(&now), &deadline);
+    do{
+      pthread_mutex_lock(lock);
+        *ret = demo_render(nc);
+        ncplane_move_yx(mplane, y, i);
+      pthread_mutex_unlock(lock);
+      if(*ret){
+        ncmultiselector_destroy(mselector);
+        return NULL;
+      }
+      struct timespec iterdelay;
+      ns_to_timespec(timespec_subtract_ns(&deadline, &now), &iterdelay);
+      char32_t wc = demo_getc(nc, &iterdelay, &ni);
+      if(wc == (char32_t)-1){
+        ncmultiselector_destroy(mselector);
+        return NULL;
+      }else if(wc){
+        pthread_mutex_lock(lock);
+          ncmultiselector_offer_input(mselector, &ni);
+          *ret = demo_render(nc);
+        pthread_mutex_unlock(lock);
+        if(*ret){
+          ncmultiselector_destroy(mselector);
+          return NULL;
+        }
+      }
+      clock_gettime(CLOCK_MONOTONIC, &now);
+    }while(timespec_to_ns(&now) < timespec_to_ns(&deadline));
   }
-  if( (*res = locked_demo_render(nc, lock)) ){
+  if( (*ret = locked_demo_render(nc, lock)) ){
     ncmultiselector_destroy(mselector);
     return NULL;
   }