Re: Putting Points and Lines into RegionPlot3D

*To*: mathgroup at smc.vnet.net*Subject*: [mg122645] Re: Putting Points and Lines into RegionPlot3D*From*: Fred Klingener <jfklingener at gmail.com>*Date*: Fri, 4 Nov 2011 06:01:41 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <j8m357$s2g$1@smc.vnet.net>

On Oct 31, 8:09 am, Brentt <brenttnew... at gmail.com> wrote: > Hello, > > How can one put points and lines into a 3D plot? > > Here is my non-working code for having a unit sphere with a line inside of > it going from the origin to 1 on the x-axis. > > origin = {0, 0, 0}; > pBox = 1.5; > RegionPlot3D[ > x^2 + y^2 + z^2 <= 1, {x, -pBox, pBox}, {y, -pBox, pBox}, {z, -pBox, > pBox}, PlotStyle -> Directive[Yellow, Opacity[0.2]], Mesh -> None, > Epilog -> {Line[{origin, {0, 1, 0}}]}] If you look at the form of your RegionPlot3D origin={0,0,0}; pBox=1.5; rp=RegionPlot3D[x^2+y^2+z^2<=1,{x,-pBox,pBox},{y,-pBox,pBox},{z,- pBox,pBox},PlotStyle->Directive[Yellow,Opacity[0.2]],Mesh->None (* ,Epilog->{Line[{origin,{0,1,0}}]}*)]; Head[rp] Dimensions[rp] Head[rp[[1]]] Head[rp[[2]]] you'll see that rp is itself just a Graphics3D with two arguments, the first a GraphicsComplex and the second is the option list. So if for some reason you don't want to compose and Show graphics (or if it drives you nuts figuring out how the composition order determines the output), you can compose a single Graphics3D: Graphics3D[ { rp[[1]] (* the RegionPlot3D GraphicsComplex *) ,Arrow[{origin,{1,1,1}}] (* your stuff *) } ,rp[[2]] (* original Options *) ] hth, Fred Klingener