mergeVertices: Merge duplicate vertices in mesh object

In rgl: 3D Visualization Using OpenGL

Description

A mesh object can have the same vertex listed twice. Each copy is allowed to have separate normals, texture coordinates, and color. However, it is more efficient to have just a single copy if those differences aren't needed. For automatic smoothing using addNormals, triangles and quads need to share vertices. This function merges identical (or similar) vertices to achieve this.

Usage

mergeVertices(mesh, 
              notEqual = NULL, 
              attribute = "vertices", 
              tolerance = sqrt(.Machine$double.eps))

Arguments

mesh	A mesh3d object.
notEqual	A logical matrix indicating that certain pairs should not be merged even if they appear identical.
attribute	Which attribute(s) should be considered in comparing vertices? A vector chosen from c("vertices", "colors", "normals", "texcoords"))
tolerance	When comparing vertices using all.equal, this tolerance will be used to ignore rounding error.

Value

A new mesh object.

Author(s)

Duncan Murdoch

See Also

as.mesh3d.rglId, which often constructs mesh objects containing a lot of duplication.

Examples

(mesh1 <- cube3d())
id <- shade3d(mesh1, col = rainbow(6), meshColor = "face")
(mesh2 <- as.mesh3d(id))
(mesh3 <- mergeVertices(mesh2))

Example output

Warning messages:
1: In rgl.init(initValue, onlyNULL) : RGL: unable to open X11 display
2: 'rgl.init' failed, running with 'rgl.useNULL = TRUE'. 
 mesh3d object with 8 vertices, 0 triangles and 6 quads.
 mesh3d object with 24 vertices, 12 triangles and 0 quads.
 mesh3d object with 8 vertices, 12 triangles and 0 quads.

rgl documentation built on Feb. 1, 2021, 3:01 a.m.