// With thanks to http://www.turiyaware.com/a-solution-to-unitys-camera-worldtoscreenpoint-causing-ui-elements-to-display-when-object-is-behind-the-camera/
public static MinMax3D GetScreenRectFromBounds(MeshFilter renderer, Camera mainCamera)
{
MinMax3D minMax = new MinMax3D (float.MaxValue, float.MinValue);
Vector3[] screenBoundsExtents = new Vector3[8];
var localBounds = renderer.sharedMesh.bounds;
bool anyPointIsInFrontOfCamera = false;
for (int i = 0; i < 8; i++) {
Vector3 localSpaceCorner = localBounds.center + Vector3.Scale (localBounds.extents, cubeCornerOffsets[i]);
Vector3 worldSpaceCorner = renderer.transform.TransformPoint (localSpaceCorner);
Vector3 viewportSpaceCorner = mainCamera.WorldToViewportPoint (worldSpaceCorner);
if (viewportSpaceCorner.z > 0) {
anyPointIsInFrontOfCamera = true;
} else {
// If point is behind camera, it gets flipped to the opposite side
// So clamp to opposite edge to correct for this
viewportSpaceCorner.x = (viewportSpaceCorner.x <= 0.5f) ? 1 : 0;
viewportSpaceCorner.y = (viewportSpaceCorner.y <= 0.5f) ? 1 : 0;
}
// Update bounds with new corner point
minMax.AddPoint (viewportSpaceCorner);
}
// All points are behind camera so just return empty bounds
if (!anyPointIsInFrontOfCamera) {
return new MinMax3D ();
}
return minMax;
}
internal static MinMax3D GetScreenRectFromBounds(MeshFilter renderer, Camera main_camera)
{
// With thanks to http://www.turiyaware.com/a-solution-to-unitys-camera-worldtoscreenpoint-causing-ui-elements-to-display-when-object-is-behind-the-camera/
var min_max = new MinMax3D(min: float.MaxValue, max: float.MinValue);
var screen_bounds_extents = new Vector3[8];
var local_bounds = renderer.sharedMesh.bounds;
var any_point_is_in_front_of_camera = false;
for (var i = 0; i < 8; i++)
{
var local_space_corner = local_bounds.center
+ Vector3.Scale(a: local_bounds.extents, b: _cube_corner_offsets[i]);
var world_space_corner = renderer.transform.TransformPoint(position: local_space_corner);
var viewport_space_corner = main_camera.WorldToViewportPoint(position: world_space_corner);
if (viewport_space_corner.z > 0)
{
any_point_is_in_front_of_camera = true;
}
else
{
// If point is behind camera, it gets flipped to the opposite side
// So clamp to opposite edge to correct for this
viewport_space_corner.x = (viewport_space_corner.x <= 0.5f) ? 1 : 0;
viewport_space_corner.y = (viewport_space_corner.y <= 0.5f) ? 1 : 0;
}
// Update bounds with new corner point
min_max.AddPoint(point: viewport_space_corner);
}
// All points are behind camera so just return empty bounds
if (!any_point_is_in_front_of_camera)
{
return(new MinMax3D());
}
return(min_max);
}