private void GetEdgePoints(BaseCamera viewerCamera, ConvexVolume volume, out Vector3 LBN, out Vector3 RTF)
{
Vector3 ViewerPosition = viewerCamera.GetEyeVector();
// Find left and right edges
Vector3 IntersectionPointC = GetLeftRightIntersectionPoint(ViewerPosition, volume.FarPlane, volume.LeftPlane);
Vector3 IntersectionPointB = GetLeftRightIntersectionPoint(ViewerPosition, volume.FarPlane, volume.RightPlane);
// Find top and bottom edges
Vector3 IntersectionPointBottom = GetTopBottomIntersectionPoint(ViewerPosition, volume.FarPlane, volume.BottomPlane);
Vector3 IntersectionPointTop = GetTopBottomIntersectionPoint(ViewerPosition, volume.FarPlane, volume.TopPlane);
float left, right, top, bottom, near, far;
// left
Dictionary <float, Vector3> projectedValues = new Dictionary <float, Vector3>();
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointB, -RightVector), IntersectionPointB);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointC, -RightVector), IntersectionPointC);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(ViewerPosition, -RightVector), ViewerPosition);
left = projectedValues[projectedValues.Keys.Max()].X;
// right
projectedValues.Clear();
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointB, RightVector), IntersectionPointB);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointC, RightVector), IntersectionPointC);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(ViewerPosition, RightVector), ViewerPosition);
right = projectedValues[projectedValues.Keys.Max()].X;
// top
projectedValues.Clear();
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointTop, UpVector), IntersectionPointTop);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointBottom, UpVector), IntersectionPointBottom);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(ViewerPosition, UpVector), ViewerPosition);
top = projectedValues[projectedValues.Keys.Max()].Y;
// bottom
projectedValues.Clear();
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointTop, -UpVector), IntersectionPointTop);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointBottom, -UpVector), IntersectionPointBottom);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(ViewerPosition, -UpVector), ViewerPosition);
bottom = projectedValues[projectedValues.Keys.Max()].Y;
// far
projectedValues.Clear();
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointB, ForwardVector), IntersectionPointB);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointC, ForwardVector), IntersectionPointC);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(ViewerPosition, ForwardVector), ViewerPosition);
far = projectedValues[projectedValues.Keys.Max()].Z;
// near
projectedValues.Clear();
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointB, -ForwardVector), IntersectionPointB);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(IntersectionPointC, -ForwardVector), IntersectionPointC);
projectedValues.Add(GeometryMath.ProjectVectorOnNormalizedVector(ViewerPosition, -ForwardVector), ViewerPosition);
near = projectedValues[projectedValues.Keys.Max()].Z;
LBN = new Vector3(left, bottom, near);
RTF = new Vector3(right, top, far);
}
