colored floor

1 files changed, 21 insertions, 8 deletions

diff --git a/raytracer.hs b/raytracer.hs
index ed0726d..c73bf13 100644
--- a/raytracer.hs
+++ b/raytracer.hs
@@ -14,7 +14,7 @@ data Sphere = Sphere Coord Double Color deriving (Show, Eq)
 
 degrees = pi / 180
 
-eye = (0, 0, 40)
+eye = (0, 0, 20)
 
 x_of (x, _, _) = x
 y_of (_, y, _) = y
@@ -29,13 +29,16 @@ sphere2 = Sphere (80, 0, 5) 20 (255,60,0)
 
 filename num = "foo/foo" ++ show num ++ ".ppm"
 
-spherepos = take 80 [0,1..]
+spherepos = take 1 [0,20..] -- take 80 [0,1..]
 
-spheres num = [Sphere (num, 2+(num/2), 5) 20 (255,60,0), sphere1]
+spheres num = [ trace ("Sphere at " ++
+                    show (round (80 * sin(num * degrees))) ++ "," ++
+                    show (round (80 * cos(num * degrees))))
+            Sphere (80 * sin(num * degrees), 80 * cos(num * degrees), 5) 10 (255,60,0), sphere1]
 
 writenum :: Double -> IO ()
 writenum num = trace ("Rendering " ++ show (filename num))
-                writeFile (filename num) (image $ spheres num)
+               writeFile (filename num) (image $ spheres num)
 
 main = mapM writenum spherepos
 
@@ -115,19 +118,29 @@ intersect_sphere source (alpha, beta) (Sphere centre radius color)
 
 intersect_point_floor :: Coord -> ScreenCoord -> (Coord, Double)
 intersect_point_floor (_, _, z) (alpha, beta) =
-                      (  (-z * (cos alpha) / (sin beta) - 2 * (cos beta) / (sin beta),
+                      (  (-z * ((cos alpha) + (cos beta)) / (sin beta),
                          -z * (sin alpha) / (sin beta),
                          0),
                       -z / (sin beta) )
 
+direction_color :: Double -> Double -> Int -> Color
+direction_color x y attn
+        | x > 0 && y > 0  = (attn, 0, 0)
+        | x <= 0 && y > 0 = (0, attn, 0)
+        | x > 0 && y <= 0 = (attn, attn, 0)
+        | otherwise       = (0, 0, attn)
+
+checkerboard_pattern :: Double -> Double -> Int -> Color
+checkerboard_pattern x y attn
+        | (round (x/floorscale) `mod` 2) == (round (y/floorscale) `mod` 2) = direction_color x y attn
+        | otherwise              = (attn, attn, attn)
+
 intersect_floor :: Coord -> ScreenCoord -> (Coord, Double, Color)
 intersect_floor source (alpha, beta)
         | beta >= 0              = ((0, 0, 0), 0, black)
         | x > (-0.5) && x < 0.5  = ((x, y, z), t, (0, attn, attn))
         | y > (-0.5) && y < 0.5  = ((x, y, z), t, (attn, attn, 0))
-        | (round (x/floorscale) `mod` 2) == (round (y/floorscale) `mod` 2) =
-                                   ((x, y, z), t, (attn, 0, 0))
-        | otherwise              = ((x, y, z), t, (attn, attn, attn))
+        | otherwise              = ((x, y, z), t, checkerboard_pattern x y attn)
         where   attn = max 0 (round (255 - 8*(sqrt t)))
                 ((x, y, z), t) = intersect_point_floor source (alpha, beta)