/// <summary>
/// Extracts perspective camera parameters from the frustum, doesn't work with orthographic frustums.
/// </summary>
/// <returns>Perspective camera parameters from the frustum</returns>
public FrustumCameraParams GetCameraParams()
{
var corners = GetCorners();
var cameraParam = new FrustumCameraParams();
cameraParam.Position = Get3PlanesInterPoint(ref this.pRight, ref this.pTop, ref this.pLeft);
cameraParam.LookAtDir = this.pNear.Normal;
cameraParam.UpDir = Vector3.Normalize(Vector3.Cross(this.pRight.Normal, this.pNear.Normal));
cameraParam.FOV = (float)((Math.PI / 2.0 - Math.Acos(Vector3.Dot(this.pNear.Normal, this.pTop.Normal))) * 2);
cameraParam.AspectRatio = (corners[6] - corners[5]).Length / (corners[4] - corners[5]).Length;
cameraParam.ZNear = (cameraParam.Position + (this.pNear.Normal * this.pNear.D)).Length;
cameraParam.ZFar = (cameraParam.Position + (this.pFar.Normal * this.pFar.D)).Length;
return(cameraParam);
}
/// <summary>
/// Creates a new frustum relaying on perspective camera parameters
/// </summary>
/// <param name="cameraParams">The camera params.</param>
/// <returns>The bounding frustum from camera params</returns>
public static BoundingFrustum FromCamera(FrustumCameraParams cameraParams)
{
return(FromCamera(cameraParams.Position, cameraParams.LookAtDir, cameraParams.UpDir, cameraParams.FOV,
cameraParams.ZNear, cameraParams.ZFar, cameraParams.AspectRatio));
}
