Revise comment about outline normals.

This commit is contained in:
Robin KAY 2022-08-09 00:52:52 +01:00
parent 02b9b7c49f
commit a05529928f

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@ -81,10 +81,15 @@ pub enum GenerateOutlineNormalsError {
/// Extension methods for [`Mesh`].
pub trait OutlineMeshExt {
/// Generates outline normals for the mesh by normalising the sum of the regular normals.
/// Generates outline normals for the mesh from the regular normals.
///
/// To the extent that outline normals are not perpendicular to the surface of the mesh,
/// this may result in non-uniform outline thickness.
/// Vertex extrusion only works for meshes with smooth surface normals. Hard edges cause
/// visual artefacts. This function generates faux-smooth normals for outlining purposes
/// by grouping vertices by their position and averaging the normals at each point. These
/// outline normals are then inserted as a separate vertex attribute so that the regular
/// normals remain untouched. However, insofar as the outline normals are not
/// perpendicular to the surface of the mesh, this technique may result in non-uniform
/// outline thickness.
///
/// This function will silently do nothing if the outline normals would be equal to the
/// regular normals.