Added Glitch Room Source code to Gitty

games/robotron/title_palette.gdshader

@@ -0,0 +1,14 @@
+shader_type canvas_item;
+render_mode unshaded;
+uniform bool animate_title = false;
+uniform int palette_step = 0;
+void fragment() {
+	vec4 pixel = texture(TEXTURE, UV) * COLOR;
+	// Only the supplied title lettering cycles; credits and sprites keep their palette.
+	if (animate_title && UV.x>0.13 && UV.x<0.86 && UV.y>0.20 && UV.y<0.49 && pixel.r>0.8 && pixel.b<0.1) {
+		vec3 palette[7] = vec3[7](vec3(1,0,0),vec3(1,0.5,0),vec3(1,1,0),vec3(0,1,0),vec3(0,1,1),vec3(1,0,1),vec3(1,1,1));
+		int index = (palette_step + (pixel.g>0.8 ? 2 : 0)) % 7;
+		pixel.rgb = palette[index];
+	}
+	COLOR = pixel;
+}