module Matrix(
mvp
) where
import Linear
import qualified LambdaCube.Linear as LC
-- | Calculating Model-View-Projection matrix, matrix in LambdaCube format
mvp :: Float -> Float -> LC.M44F
mvp !aspect !t = convLC $ mvp' aspect t
convLC :: M44 Float -> LC.M44F
convLC (V4 !a !b !c !d) = LC.V4 (cv a) (cv b) (cv c) (cv d)
where
cv (V4 !x !y !z !w) = LC.V4 x y z w
-- | Calculating Model-View-Projection matrix
mvp' :: Float -> Float -> M44 Float
mvp' !aspect !t = transpose $ projMatrix !*! cameraMatrix !*! modelMatrix
where
modelMatrix = quatMatrix $ axisAngle (V3 1 0 1) t
cameraMatrix = lookAt eye (V3 0 0 0) (V3 0 1 0)
eye = rotate (axisAngle (V3 0 1 0) t) (V3 0 0 (-5))
projMatrix = perspective (pi/3) aspect 0.1 100
-- | Transform quaternion to rotation matrix
quatMatrix :: Quaternion Float -> M44 Float
quatMatrix q@(Quaternion !w (V3 !x !y !z)) = V4
(V4 m00 m01 m02 0)
(V4 m10 m11 m12 0)
(V4 m20 m21 m22 0)
(V4 0 0 0 1)
where
s = 2 / norm q
x2 = x * s
y2 = y * s
z2 = z * s
xx = x * x2
xy = x * y2
xz = x * z2
yy = y * y2
yz = y * z2
zz = z * z2
wx = w * x2
wy = w * y2
wz = w * z2
m00 = 1 - (yy + zz)
m10 = xy - wz
m20 = xz + wy
m01 = xy + wz
m11 = 1 - (xx + zz)
m21 = yz - wx
m02 = xz - wy
m12 = yz + wx
m22 = 1 - (xx + yy)