| Austin Schuh | 405fa6c | 2015-09-06 18:13:55 -0700 | [diff] [blame] | 1 | (* |
| 2 | PolytopeSkeleton.m, |
| 3 | by Komei Fukuda, fukuda@ifor.math.ethz.ch |
| 4 | Version March 3, 1999. |
| 5 | -- This Needs View3D package --- |
| 6 | *) |
| 7 | |
| 8 | Visible[ineq_Integer, {a_,b_}, viewpoint_]:= |
| 9 | If[N[a[[ineq]].viewpoint] >= N[b[[ineq]]], True, False]; |
| 10 | |
| 11 | Visible[{a_,b_}, viewpoint_]:= |
| 12 | Map[Visible[#,{a,b},viewpoint]&, Range[Length[b]]]; |
| 13 | |
| 14 | VisibleSkeleton[vertices_,ecd_, ead_, {a_, b_},viewpoint_]:= |
| 15 | Block[{grtemp, edgelist, i, visibility, viseges, invisedges, visibles,invisibles}, |
| 16 | edgelist={}; |
| 17 | Do[ edgelist=Join[edgelist,Map[{i, #}&, ead[[i]]]], |
| 18 | {i,1,Length[ead]} |
| 19 | ];edgelist=Select[edgelist,#[[1]]<#[[2]]&]; |
| 20 | visibility=Flatten[Position[Visible[{a, b},viewpoint],True]]; |
| 21 | visedges=Select[edgelist, |
| 22 | (Intersection[visibility,ecd[[#[[1]]]],ecd[[#[[2]]]] ] != {}) &]; |
| 23 | invisedges=Complement[edgelist,visedges]; |
| 24 | visibles=(vertices[[#]]&) /@ visedges; |
| 25 | invisibles=(vertices[[#]]&) /@ invisedges; |
| 26 | grtemp=Join[{Thickness[ 0.0085]}, |
| 27 | Line /@ visibles, |
| 28 | {Thickness[ 0.0035], Dashing[{0.01,0.012}]}, Line /@ invisibles]; |
| 29 | grtemp |
| 30 | ]; |
| 31 | |
| 32 | VisibleSkeleton2[vertices_,ecd_, ead_, flist_,{a_, b_},viewpoint_]:= |
| 33 | Block[{grtemp, edgelist, i, edgelist0, visibility, viseges, invisedges, visibles,invisibles}, |
| 34 | edgelist0={}; |
| 35 | Do[ edgelist0=Join[edgelist0,Map[{i, #}&, ead[[i]]]], |
| 36 | {i,1,Length[ead]} |
| 37 | ];edgelist0=Select[edgelist0,#[[1]]<#[[2]]&]; |
| 38 | edgelist=Select[edgelist0,(Intersection[ecd[[#[[1]]]],ecd[[#[[2]]]],flist] != {})&]; |
| 39 | visibility=Flatten[Position[Visible[{a, b},viewpoint],True]]; |
| 40 | visedges=Select[edgelist, |
| 41 | (Intersection[visibility,ecd[[#[[1]]]],ecd[[#[[2]]]] ] != {}) &]; |
| 42 | invisedges=Complement[edgelist,visedges]; |
| 43 | visibles=(vertices[[#]]&) /@ visedges; |
| 44 | invisibles=(vertices[[#]]&) /@ invisedges; |
| 45 | grtemp=Join[{Thickness[ 0.0085]}, |
| 46 | Line /@ visibles, |
| 47 | {Thickness[ 0.0035], Dashing[{0.01,0.012}]}, Line /@ invisibles]; |
| 48 | grtemp |
| 49 | ]; |
| 50 | |
| 51 | getMmaViewPoint[vp_,gr_]:= |
| 52 | ViewPointFromUser[vp, |
| 53 | FullOptions[gr,PlotRange], |
| 54 | FullOptions[gr,BoxRatios] |
| 55 | ]; |
| 56 | |
| 57 | getUserViewPoint[vp_,gr_]:= |
| 58 | ViewPointToUser[vp, |
| 59 | FullOptions[gr,PlotRange], |
| 60 | FullOptions[gr,BoxRatios] |
| 61 | ]; |
| 62 | |
| 63 | circle[alpha_, r_:2, h_:2]:= |
| 64 | {r*Cos[alpha], r*Sin[alpha], h} |
| 65 | |
| 66 | (* end of PolytopeSkeleton.m *) |