Add colours.rgb8(r, g, b)/colours.rgb8(hex)

src/main/resources/assets/computercraft/lua/rom/apis/colors

@@ -25,13 +25,23 @@ function combine( ... )
 end
 
 function subtract( colors, ... )
-	local r = colors
-	for n,c in ipairs( { ... } ) do
-		r = bit32.band(r, bit32.bnot(c))
-	end
-	return r
+    local r = colors
+    for n,c in ipairs( { ... } ) do
+        r = bit32.band(r, bit32.bnot(c))
+    end
+    return r
 end
 
 function test( colors, color )
     return ((bit32.band(colors, color)) == color)
 end
+
+function rgb8( r, g, b )
+    if type(r) == "number" and g == nil and b == nil then
+        return bit32.band( bit32.rshift( r, 16 ), 0xFF ) / 255, bit32.band( bit32.rshift( r, 8 ), 0xFF ) / 255, bit32.band( r, 0xFF ) / 255
+    elseif type(r) == "number" and type(g) == "number" and type(b) == "number" then
+        return r / 255, g / 255, b / 255
+    else
+        return nil
+    end
+end