Convert a scimesh mesh to rgl tmesh3d format

Builds an rgl-compatible triangular mesh from a scimesh mesh descriptor so that the result can be used with rgl::shade3d() or other rgl functions.

Usage

mesh_to_rgl(mesh, color = NULL, face_color = NULL)

Arguments

mesh: A scimesh mesh descriptor list with vertices (Nx3 matrix) and triangles (Mx3 integer matrix, 1-based).
color: Optional per-vertex colour, either a single length-4 RGBA vector (applied to all vertices) or an Nx4 matrix.
face_color: Optional per-face colour (Mx4 matrix).

Value

A list with components vb (4xN homogeneous coordinates), it (3xM 1-based index matrix), and optionally normals and mat (material), suitable for use with rgl's tmesh3d() and shade3d().

Examples

mesh <- generate_cuboid(c(0, 0, 0), c(1, 1, 1))
rgl_mesh <- mesh_to_rgl(mesh)
str(rgl_mesh)
#> List of 4
#>  $ vb     : num [1:4, 1:24] -1 -1 1 1 1 -1 1 1 1 1 ...
#>  $ it     : int [1:3, 1:12] 1 2 3 1 3 4 5 6 7 5 ...
#>  $ normals: num [1:3, 1:24] 0 0 1 0 0 1 0 0 1 0 ...
#>  $ mat    :List of 1
#>   ..$ color: num [1:4, 1:24] 0.7 0.7 0.7 1 0.7 ...