public (float Near, float Far) GetClippingPlanes(Transform world, Vector3 cameraPosition, Quaternion cameraOrientation)
{
Vector3[] clipPoints = new Vector3[4] {
new Vector3(-1, 0, HIGHWAY_ADD), new Vector3(1, 0, HIGHWAY_ADD), new Vector3(-1, 0, -HIGHWAY_LENGTH), new Vector3(1, 0, -HIGHWAY_LENGTH)
};
float minClipDist = float.MaxValue;
float maxClipDist = float.MinValue;
Vector3 cameraForward = Vector3.Transform(new Vector3(0, 0, -1), cameraOrientation);
for (int i = 0; i < 4; i++)
{
float clipDist = SignedDistance(Vector3.Transform(clipPoints[i], world.Matrix) - cameraPosition, cameraForward);
minClipDist = Math.Min(minClipDist, clipDist);
maxClipDist = Math.Max(maxClipDist, clipDist);
}
float clipNear = Math.Max(0.01f, minClipDist);
float clipFar = maxClipDist;
// TODO(local): see if the default epsilon is enough? There's no easy way to check clip planes manually right now
if (clipNear.ApproxEq(clipFar))
{
clipFar = clipNear + 0.001f;
}
return(clipNear, clipFar);
Vector3 V3Project(Vector3 a, Vector3 b) => b * (Vector3.Dot(a, b) / Vector3.Dot(b, b));
float SignedDistance(Vector3 point, Vector3 ray)
{
Vector3 projected = V3Project(point, ray);
return(MathL.Sign(Vector3.Dot(ray, projected)) * projected.Length());
}
}
public static bool FactorIsTrivial(this float factor)
{
return(factor.ApproxEq(Constants.TRIVIAL_FACTOR));
}