search for: qmesh3d

...2.03 1.00 6.74 ... $ ib : num [1:4, 1:384] 1 195 99 196 51 197 99 195 27 198 ... $ primitivetype: chr "quad" $ homogeneous : logi TRUE $ material : list() $ normals : num [1:4, 1:386] 0.290 -0.902 -0.320 1.000 0.635 ... - attr(*, "class")= chr "qmesh3d" -Michael -- Michael Friendly Email: friendly AT yorku DOT ca Professor, Psychology Dept. York University Voice: 416 736-5115 x66249 Fax: 416 736-5814 4700 Keele Street http://www.math.yorku.ca/SCS/friendly.html Toronto, ONT M3J 1P3 CANADA

...pting "homogeneous = F" # # http://www.mail-archive.com/r-help at r-project.org/msg58482.html # # One would think that each vertex would have 3 # coordinates (x,y,z) what does the fourth one in # the definition of the variable vertices stand # for. # # By default qmesh3d uses 4-coordinate homogeneous # coordinates, because that's the coordinate system # used by OpenGL. See the ?rgl::matrices help topic # for a description of how they work. # # Report formatting # # Note that -1.0 * 0.0 gives -0.0 which 'formatC' # then outputs as &quot...

For a paper dealing with generalized ellipsoids, I want to illustrate in 3D an ellipsoid that is unbounded in one dimension, having the shape of an infinite cylinder along, say, z, but whose cross-section in (x,y) is an ellipse, say, given by the 2x2 matrix cov(x,y). I've looked at rgl:::cylinder3d, but don't see any way to make it accomplish this. Does anyone have any ideas? thx,

Does anyone have a way of producing solid shapes other than spheres in rgl? I am using rgl to produce a simple visualisation of a forest model results using "lollipops". Its just a bit of fun, but as many of the trees are pines I would like to depict their crowns as cones. If there is a solution I need it to work under windows. Here is the example. library(rgl) library(misc3d)

Hi folks, I'd like to use scatter3d (which is in R commander) to plot more than one dataset in the same graph, each dataset with a different color. The kind of stuff you would do with "holdon" in Matlab. I read a recent message that was posted to this list with a similar problem, but I couldn't understand the reply. Could someone give me one example? How do you plot subgroups