private static Ray3D RayFromPerspectiveCameraPoint(PerspectiveCamera camera, Point point, Size viewSize)
{
Point3D position = camera.Position;
Vector3D lookDirection = camera.LookDirection;
Vector3D upDirection = camera.UpDirection;
Transform3D transform = camera.Transform;
double nearPlaneDistance = camera.NearPlaneDistance;
double farPlaneDistance = camera.FarPlaneDistance;
double num1 = camera.FieldOfView * (Math.PI / 180.0);
Point normalizedPoint = CameraRayHelpers.GetNormalizedPoint(point, viewSize);
double aspectRatio = CameraRayHelpers.GetAspectRatio(viewSize);
double num2 = Math.Tan(num1 / 2.0);
double num3 = aspectRatio / num2;
double num4 = 1.0 / num2;
Vector3D vector = new Vector3D(normalizedPoint.X / num4, normalizedPoint.Y / num3, -1.0);
Matrix3D viewMatrix = CameraRayHelpers.CreateViewMatrix((Transform3D)null, ref position, ref lookDirection, ref upDirection);
viewMatrix.Invert();
Vector3D vector3D = viewMatrix.Transform(vector);
Point3D point3D = position + nearPlaneDistance * vector3D;
vector3D.Normalize();
if (transform != null && transform != Transform3D.Identity)
{
point3D = transform.Transform(point3D);
vector3D = transform.Transform(vector3D);
}
return(new Ray3D(point3D, vector3D));
}
private static Ray3D RayFromOrthographicCameraPoint(OrthographicCamera camera, Point point, Size viewSize)
{
Point3D position = camera.Position;
Vector3D lookDirection = camera.LookDirection;
Vector3D upDirection = camera.UpDirection;
Transform3D transform = camera.Transform;
double nearPlaneDistance = camera.NearPlaneDistance;
double farPlaneDistance = camera.FarPlaneDistance;
double width = camera.Width;
Point normalizedPoint = CameraRayHelpers.GetNormalizedPoint(point, viewSize);
double aspectRatio = CameraRayHelpers.GetAspectRatio(viewSize);
double num1 = width;
double num2 = num1 / aspectRatio;
Point3D point1 = new Point3D(normalizedPoint.X * (num1 / 2.0), normalizedPoint.Y * (num2 / 2.0), -nearPlaneDistance);
Vector3D vector = new Vector3D(0.0, 0.0, -1.0);
Matrix3D viewMatrix = CameraRayHelpers.CreateViewMatrix((Transform3D)null, ref position, ref lookDirection, ref upDirection);
viewMatrix.Invert();
Point3D point3D = viewMatrix.Transform(point1);
Vector3D vector3D = viewMatrix.Transform(vector);
if (transform != null && transform != Transform3D.Identity)
{
point3D = transform.Transform(point3D);
vector3D = transform.Transform(vector3D);
}
return(new Ray3D(point3D, vector3D));
}
private static Ray3D RayFromMatrixCameraPoint(MatrixCamera camera, Point point, Size viewSize)
{
Point normalizedPoint = CameraRayHelpers.GetNormalizedPoint(point, viewSize);
Matrix3D matrix3D = camera.ViewMatrix * camera.ProjectionMatrix;
if (!matrix3D.HasInverse)
{
throw new NotSupportedException(ExceptionStringTable.NeedToHandleSingularMatrixCameras);
}
matrix3D.Invert();
Point4D point4D = new Point4D(normalizedPoint.X, normalizedPoint.Y, 0.0, 1.0) * matrix3D;
Point3D origin = new Point3D(point4D.X / point4D.W, point4D.Y / point4D.W, point4D.Z / point4D.W);
Vector3D direction = new Vector3D(matrix3D.M31 - matrix3D.M34 * origin.X, matrix3D.M32 - matrix3D.M34 * origin.Y, matrix3D.M33 - matrix3D.M34 * origin.Z);
direction.Normalize();
if (point4D.W < 0.0)
{
direction = -direction;
}
return(new Ray3D(origin, direction));
}