boxdemo: finally do something worth doing

src/demo/boxdemo.c

@@ -2,9 +2,37 @@
 #include <unistd.h>
 #include "demo.h"
 
+static int
+reload_corners(struct ncplane* n, cell* ul, cell* ur, cell* ll, cell* lr){
+  int dimy, dimx;
+
+  ncplane_dim_yx(n, &dimy, &dimx);
+  cell c = CELL_TRIVIAL_INITIALIZER;
+  if(ncplane_at_yx(n, 1, dimx - 1, &c) < 0){
+    cell_release(n, &c);
+    return -1;
+  }
+  ul->channels = c.channels;
+  if(ncplane_at_yx(n, dimy - 1, dimx - 1, &c) < 0){
+    cell_release(n, &c);
+    return -1;
+  }
+  ur->channels = c.channels;
+  if(ncplane_at_yx(n, dimy - 1, 0, &c) < 0){
+    cell_release(n, &c);
+    return -1;
+  }
+  lr->channels = c.channels;
+  if(ncplane_at_yx(n, 1, 0, &c) < 0){
+    cell_release(n, &c);
+    return -1;
+  }
+  ll->channels = c.channels;
+  cell_release(n, &c);
+  return 0;
+}
+
 int box_demo(struct notcurses* nc){
-  struct timespec iterdelay;
-  timespec_div(&demodelay, 256, &iterdelay);
   struct ncplane* n = notcurses_stdplane(nc);
   ncplane_erase(n);
   cell ul = CELL_TRIVIAL_INITIALIZER, ll = CELL_TRIVIAL_INITIALIZER;
@@ -13,10 +41,6 @@ int box_demo(struct notcurses* nc){
   if(cells_double_box(n, 0, 0, &ul, &ur, &ll, &lr, &hl, &vl)){
     return -1;
   }
-  struct timespec start, now;
-  clock_gettime(CLOCK_MONOTONIC, &start);
-  int zbonus = 40;
-  int zbonusdelta = 20;
   int ylen, xlen;
   ncplane_dim_yx(n, &ylen, &xlen);
   // target grid is 7x7
@@ -50,35 +74,61 @@ int box_demo(struct notcurses* nc){
   if(ncplane_putstr_aligned(n, ytargbase++, NCALIGN_CENTER, "┗━━┻━━┛") < 0){
     return -1;
   }
-  for(int idx = 0 ; idx < 256 ; ++idx){
-    int y = 1, x = 0;
+  if(cell_set_fg_rgb(&ul, 0xff, 0, 0)){
+    return -1;
+  }
+  if(cell_set_bg_rgb(&ul, 20, 40, 20)){
+    return -1;
+  }
+  if(cell_set_fg_rgb(&ur, 0, 0xff, 0)){
+    return -1;
+  }
+  if(cell_set_bg_rgb(&ur, 20, 40, 20)){
+    return -1;
+  }
+  if(cell_set_fg_rgb(&ll, 0, 0, 0xff)){
+    return -1;
+  }
+  if(cell_set_bg_rgb(&ll, 20, 40, 20)){
+    return -1;
+  }
+  if(cell_set_fg_rgb(&lr, 0xff, 0xff, 0xff)){
+    return -1;
+  }
+  if(cell_set_bg_rgb(&lr, 20, 40, 20)){
+    return -1;
+  }
+  int y = 1, x = 0;
+  ncplane_dim_yx(n, &ylen, &xlen);
+  --ylen;
+  while(ylen - y >= targy && xlen - x >= targx){
+    if(ncplane_cursor_move_yx(n, y, x)){
+      return -1;
+    }
+    if(ncplane_box_sized(n, &ul, &ur, &ll, &lr, &hl, &vl, ylen, xlen,
+                          NCBOXGRAD_LEFT | NCBOXGRAD_BOTTOM |
+                          NCBOXGRAD_RIGHT | NCBOXGRAD_TOP)){
+      return -1;
+    }
+    ylen -= 2;
+    xlen -= 2;
+    ++y;
+    ++x;
+  }
+  DEMO_RENDER(nc);
+  int iters = 50;
+  struct timespec iterdelay;
+  ns_to_timespec(timespec_to_ns(&demodelay) * 3 / iters, &iterdelay);
+  nanosleep(&iterdelay, NULL);
+  while(iters--){
+    if(reload_corners(n, &ul, &ur, &ll, &lr)){
+      return -1;
+    }
+    y = 1;
+    x = 0;
     ncplane_dim_yx(n, &ylen, &xlen);
     --ylen;
     while(ylen - y >= targy && xlen - x >= targx){
-      if(cell_set_fg_rgb(&ul, idx, 255 - (y * 2), 255 - idx)){
-        return -1;
-      }
-      if(cell_set_bg_rgb(&ul, 20, zbonus, 20)){
-        return -1;
-      }
-      if(cell_set_fg_rgb(&ur, idx / 2, zbonus, (255 - idx) / 2)){
-        return -1;
-      }
-      if(cell_set_bg_rgb(&ur, 20, zbonus, 20)){
-        return -1;
-      }
-      if(cell_set_fg_rgb(&ll, idx / 2, zbonus, (255 - idx) / 2)){
-        return -1;
-      }
-      if(cell_set_bg_rgb(&ll, 20, zbonus, 20)){
-        return -1;
-      }
-      if(cell_set_fg_rgb(&lr, 255 - idx, 255 - (y * 2), zbonus)){
-        return -1;
-      }
-      if(cell_set_bg_rgb(&lr, 20, zbonus, 20)){
-        return -1;
-      }
       if(ncplane_cursor_move_yx(n, y, x)){
         return -1;
       }
@@ -94,11 +144,6 @@ int box_demo(struct notcurses* nc){
     }
     DEMO_RENDER(nc);
     nanosleep(&iterdelay, NULL);
-    clock_gettime(CLOCK_MONOTONIC, &now);
-    if((zbonus += zbonusdelta > 255) || zbonus < 0){
-      zbonusdelta = -zbonusdelta;
-      zbonus += zbonusdelta;
-    }
   }
   cell_release(n, &ul);
   cell_release(n, &ur);

src/demo/demo.c

@@ -446,7 +446,6 @@ int main(int argc, char** argv){
     if(menu_create(nc) == NULL){
       goto err;
     }
-fprintf(stderr, "START THEM DEMOS [%s]\n", spec);
     if(ext_demos(nc, spec, ignore_failures) == NULL){
       goto err;
     }