A rectangular face is an optimized face representation that represents a face that is rectangular and that lies parallel on a coordinate plane (either xy-, xz-, or yz-plane).
This face specifies its position by using two points, the minimum corner and maximum corner. Because the face must lie parallel to a coordinate plane, the corner points share a common coordinate value. For example, if the rectangular face lies on the xy-plane, the corner points share a common z-value.
The surface normal of this rectangular face depends on the order of the specification of the min and max points, as described in the following table.
|
Plane to Which Rectangle is Parallel |
Order of Specification of (Coordinates of) the Corners |
Direction of the Surface Normal |
|
XY |
Min-corner, max-corner |
Positive Z-axis |
|
YZ |
Min-corner, max-corner |
Positive X-axis |
|
XZ |
Min-corner, max-corner |
Positive Y-axis |
|
XY |
Max-corner, min-corner |
Negative Z-axis |
|
YZ |
Max-corner, min-corner |
Negative X-axis |
|
XZ |
Max-corner, min-corner |
Negative Y-axis |
With conjunction of a 4×4 transformation matrix, an IFMERectangleFace can be used to represent rectangular faces that are not parallel to the coordinate planes. This matrix can store affine transformations.
Contains: None
Contained by: IFMECompositeSurface, IFMEMultiSurface