grid demo

src/bin/demo.c

@@ -95,6 +95,9 @@ int main(int argc, char** argv){
     goto err;
   }
   sleep(1);
+  if(grid_demo(nc)){
+    goto err;
+  }
   if(box_demo(nc)){
     goto err;
   }

src/bin/demo.h

@@ -11,6 +11,7 @@ extern "C" {
 
 int widecolor_demo(struct notcurses* nc, struct ncplane* n);
 int box_demo(struct notcurses* nc);
+int grid_demo(struct notcurses* nc);
 
 #ifdef __cplusplus
 }

src/bin/grid.c

@@ -0,0 +1,71 @@
+#include <unistd.h>
+#include "demo.h"
+
+// red across, blue down, green from UL to LR
+int grid_demo(struct notcurses* nc){
+  int maxx, maxy;
+  notcurses_term_dimyx(nc, &maxy, &maxx);
+  int rs = 256 / maxx;
+  int gs = 256 / (maxx + maxy);
+  int bs = 256 / maxy;
+  int y, x;
+  struct ncplane* n = notcurses_stdplane(nc);
+  cell ul, ll, cl, cr, lc, lr, ur, uc, cc;
+  cell_init(&ul);
+  cell_init(&uc);
+  cell_init(&cl);
+  cell_init(&cr);
+  cell_init(&ll);
+  cell_init(&lc);
+  cell_init(&lr);
+  cell_init(&ur);
+  cell_init(&cc);
+  cell_load(n, &ul, "┍");
+  cell_load(n, &uc, "┯");
+  cell_load(n, &ur, "┑");
+  cell_load(n, &cl, "┝");
+  cell_load(n, &cc, "┿");
+  cell_load(n, &cr, "┥");
+  cell_load(n, &ll, "┕");
+  cell_load(n, &lc, "┷");
+  cell_load(n, &lr, "┙");
+  ncplane_cursor_move_yx(n, 0, 0);
+  y = 0;
+
+  // top line
+  cell_set_fg(&ul, 255, 255, 255);
+  ncplane_putc(n, &ul);
+  for(x = 1 ; x < maxx - 1 ; ++x){
+    cell_set_fg(&uc, 255 - rs * x, 255 - gs * (x + y), 255);
+    ncplane_putc(n, &uc);
+  }
+  cell_set_fg(&ur, 1, 255 - gs * (x + y), 255);
+  ncplane_putc(n, &ur);
+
+  // center
+  for(y = 1 ; y < maxy - 1 ; ++y){
+    cell_set_fg(&cl, 255, 255 - gs * (x + y), 255 - bs * y);
+    ncplane_putc(n, &cl);
+    for(x = 1 ; x < maxx - 1 ; ++x){
+      cell_set_fg(&cc, 255 - rs * x, 255 - gs * (x + y), 255 - bs * y);
+      ncplane_putc(n, &cc);
+    }
+    cell_set_fg(&cr, 1, 255 - gs * (x + y), 255 - bs * y);
+    ncplane_putc(n, &cr);
+  }
+
+  // bottom line
+  cell_set_fg(&ll, 255, 255 - gs * (x + y), 1);
+  ncplane_putc(n, &ll);
+  for(x = 1 ; x < maxx - 1 ; ++x){
+    cell_set_fg(&lc, 255 - rs * x, 255 - gs * (x + y), 1);
+    ncplane_putc(n, &lc);
+  }
+  cell_set_fg(&lr, 1, 255 - gs * (x + y), 1);
+  ncplane_putc(n, &lr);
+
+  // render!
+  notcurses_render(nc);
+  sleep(1);
+  return 0;
+}