add keys for more paint colors.

README.md

@@ -12,6 +12,8 @@ there's a demo video at `/assets/demo_video.webm`.
 
 - arrow keys: move around.
 - QWEASD: paint with RGBYCM colors, respectively.
+- ZX: paint with background colors.
+- CV: paint with black and white.
 - space: create box.
 - backspace: delete/clear/empty tiles to your left and right, and where you're standing.
 

js/player.mjs

@@ -57,9 +57,17 @@ function set_painting_key (key, color) {
 	});
 }
 
+// RGB
 set_painting_key("q", "#f00");
 set_painting_key("w", "#0f0");
 set_painting_key("e", "#00f");
+// YCM
 set_painting_key("a", "#ff0");
 set_painting_key("s", "#0ff");
 set_painting_key("d", "#f0f");
+// background colors
+set_painting_key("z", "#888");
+set_painting_key("x", "#aaa");
+// black and white
+set_painting_key("c", "#000");
+set_painting_key("v", "#fff");