IFC 4.3.0.1 (IFC4X3_TC1)

# 8.8.3.39 IfcSphere

## 8.8.3.39.1 Semantic definition

The IfcSphere is a Construction Solid Geometry (CSG) 3D primitive. It is a solid where all points at the surface have the same distance from the center point. The inherited Position attribute defines the IfcAxisPlacement3D and provides:

• SELF\IfcCsgPrimitive3D.Position: The location and orientation of the axis system for the primitive.
• SELF\IfcCsgPrimitive3D.Position.Location: The center of the sphere.
• SELF\IfcCsgPrimitive3D.Position.Position[3]: The z axis points at its positive direction towards the north pole, and by its negative directions towards the south pole.

Texture Use Definition

Textures are aligned facing upright with origin at the back (+Y direction) revolving counter-clockwise. Textures are stretched or repeated to the extent of the circumference at the equator according to RepeatS and RepeatT.

Figure 8.8.3.39.B illustrates default texture mapping with a clamped texture (RepeatS=False and RepeatT=False). The image on the left shows the texture where the S axis points to the right and the T axis points up. The image on the right shows the texture applied to the geometry where the X axis points back to the right, the Y axis points back to the left, and the Z axis points up.

## 8.8.3.39.4 Formal representation

ENTITY IfcSphere
SUBTYPE OF (IfcCsgPrimitive3D);
END_ENTITY;