public override bool CalculateShadow(ref Matrix4x4 matrix, ref float ratio)
{
if (base.CalculateShadow(ref matrix, ref ratio) == true)
{
if (Texture != null)
{
if (SgtHelper.Enabled(RingMesh) == true)
{
RadiusMin = RingMesh.RadiusMin;
RadiusMax = RingMesh.RadiusMax;
}
var direction = default(Vector3);
var position = default(Vector3);
var color = default(Color);
SgtHelper.CalculateLight(Light, transform.position, null, null, ref position, ref direction, ref color);
var rotation = Quaternion.FromToRotation(direction, Vector3.back);
var squash = Vector3.Dot(direction, transform.up); // Find how squashed the ellipse is based on light direction
var width = transform.lossyScale.x * RadiusMax;
var length = transform.lossyScale.z * RadiusMax;
var axis = rotation * transform.up; // Find the transformed up axis
var spin = Quaternion.LookRotation(Vector3.forward, new Vector2(-axis.x, axis.y)); // Orient the shadow ellipse
var scale = SgtHelper.Reciprocal3(new Vector3(width, length * Mathf.Abs(squash), 1.0f));
var skew = Mathf.Tan(SgtHelper.Acos(-squash));
var shadowT = SgtHelper.Translation(-transform.position);
var shadowR = SgtHelper.Rotation(spin * rotation); // Spin the shadow so lines up with its tilt
var shadowS = SgtHelper.Scaling(scale); // Scale the ring into an oval
var shadowK = SgtHelper.ShearingZ(new Vector2(0.0f, skew)); // Skew the shadow so it aligns with the ring plane
matrix = shadowS * shadowK * shadowR * shadowT;
ratio = SgtHelper.Divide(RadiusMax, RadiusMax - RadiusMin);
return(true);
}
}
return(false);
}
