Analysis Point

An analysis point consists of a position and a direction vector. It's typically generated as a representation of an underlying surface and generally, the direction vector is perpendicular to the surface associated with the analysis point, which implies it aligns with the normal vector of the surface at that point.

Two different analysis points, one with a vertical direction that is sampled on a horizontal surface and one with a horizontal direction that is sampled on a vertical surface.

Position

The position of the analysis point. For example the centre point of a surface representing a window.

Warning

For ray-tracing based analyses, rays are often traced from the position of the analysis point. If the analysis point is sampled from geometry that is added to the scene there is a risk that the rays from the position intersect with said geometry. It is therefore recommended that the position of the analysis point is moved slightly away from the geometry it is sampled from in order to mitigate this risk.

Direction

The direction of the analysis point, often used to direct the rays that will be traced throughout the scene. This vector has to have a length larger than 0. If the analysis point is sampled from geometry then the direction should usually be orthogonal to the surface of the geometry.

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