Font.hs

-- Bitmap font
module Font (
	Font(..),
	fontPut,
	fontPutc
) where

import Graphics.UI.SDL
import Control.Monad (zipWithM_)
import Data.Char (ord)

data Font = Font {
	fontSurface :: Surface,
	fontWidth :: Int,
	fontHeight :: Int,
	fontXN :: Int
	}


-- Put string
fontPut :: Font -> Surface -> Int -> Int -> String -> IO ()
fontPut font sur x y str = zipWithM_ (\i c -> fontPutc font sur i y c) [x..] str

-- Put char
fontPutc :: Font -> Surface -> Int -> Int -> Char -> IO Bool
fontPutc font sur x y c = do
	blitSurface (fontSurface font) (Just rc) sur (Just $ Rect (x * fontWidth font) (y * fontHeight font) w h)
	where
		ic = ord c - ord ' '
		u = (ic `mod` xn) * w
		v = (ic `div` xn) * h
		rc = Rect u v w h

		xn = fontXN font
		w = fontWidth font
		h = fontHeight font