Re: Why are my 3D plots blue?

*To*: mathgroup at smc.vnet.net*Subject*: [mg114360] Re: Why are my 3D plots blue?*From*: John Fultz <jfultz at wolfram.com>*Date*: Thu, 2 Dec 2010 05:38:49 -0500 (EST)

On Wed, 1 Dec 2010 02:10:11 -0500 (EST), Joseph Gwinn wrote: > In article <id2eko$d5t$1 at smc.vnet.net>, John Fultz <jfultz at wolfram.com> > wrote: > >> On Mon, 29 Nov 2010 06:07:39 -0500 (EST), Joseph Gwinn wrote: >>> In article <ictfvj$mi6$1 at smc.vnet.net>, John Fultz >>> <jfultz at wolfram.com> >>> wrote: >>> >>>> If you can move the Dynamic inside of the Graphics3D[], you'll have >>>> a >>>> much >>>> better experience. I.e., instead of... >>>> >>>> Dynamic[stuff; Graphics3D[{dirs}, opts]] >>>> >>>> do this... >>>> >>>> Graphics3D[Dynamic[stuff; {dirs}], opts] >>>> >>> I will try this. >>> >>> Will something like: >>> >>> DynamicModule[{local variables}, >>> Dynamic[stuff]; >>> Graphics3D[ Dynamic[graphic directives], opts] >>> ] >>> >>> also work? I've tried some similar approaches, but the graphics didn't >>> respond to mouse motion, don't know exactly why. I would have thought >>> that a local variable x would be linked by the Dynamic functions. I >>> assume I didn't quite do it right. >>> >> No, that won't work. To understand why, read through my post here... >> >> http://forums.wolfram.com/mathgroup/archive/2009/Feb/msg00424.html >> >> For a further library of stuff that I've written about Dynamic, see >> here... >> >> http://forums.wolfram.com/mathgroup/archive/2010/May/msg00440.html >> > Thanks. I'll study these. I've read all the relevant documentation, > and still don't really have a complete grasp of Dynamic and its friends. > > >>>> and if the options should be dynamically updated, put individual >>>> Dynamics in the option values. >>>> >>> Will this allow me to track the current value of for instance >>> ViewMatrix? I have tried Dynamic[ViewMatrix] to no effect, getting an >>> unchanging empty list {} in response. >>> >> Alas, there's a bug here. You're the first to uncover this, it appears. >> I've made a report to the appropriate developers. >> > Ahh. Thanks. I would guess that you were already able to reproduce the > problem, but here are some miscreants I tried: > > Graphics3D[{Text[Options[Dynamic[ViewMatrix]],{0,0,0}],Text[Options[Dynam > ic[ViewPoint]],{0,0,1}]},ViewPoint->{Pi,Pi/2,2},SphericalRegion->True] > > Graphics3D[{Text[Dynamic[Options[ViewMatrix]],{0,0,0}],Text[Options[ViewP > oint],{0,0,1}]},ViewPoint->{Pi,Pi/2,2},SphericalRegion->True] > > Dynamic[Graphics3D[{Text[Options[ViewMatrix],{0,0,0}],Text[Options[ViewPo > int],{0,0,1}]},ViewPoint->{Pi,Pi/2,2},SphericalRegion->True]] > > >>>> The basic problem here is that the Graphics3D is being recreated over >>>> and over again and Mathematica is getting confused about what exactly >>>> should be selected. In typical examples, this kind of thing works >>>> fine, but your code, for reasons I haven't investigated, stresses this >>>> enough to expose the problem. By preventing the Graphics3D wrapper >>>> from being recreated, you can avoid the problem entirely. >>>> >>> OK. Sounds like it will be faster too. >>> >> Yes, but probably only marginally so. >> > One thing I have been doing is to generate 3D plots in two pieces, with > the unchanging background done once (with no Dynamic calls), the > changing stuff generated in another Graphics3D, then using Show to merge > things. The pattern is something like: > > staticplot==Graphics3d[<background scenery>]; (* No Dynamic stuff *) > > DynamicModule[{local vars}, > dynamicplot==Graphics3D[Dynamic[<stuff that moves>]]; > Show[staticplot,dynamicplot] ] > > Comments? It this complication worthwhile? Yes, this is good. Alternatively, you could have also done... Graphics3D[{<static stuff>, Dynamic[<dynamic stuff>]}] >>> Another perhaps related effect discovered by accident is that moving >>> the 3D mouse while Mathematica is doing the initial evaluation of the >>> notebook can cause Mathematica to crash with a SEGFAULT error. This >>> happened a few days ago, and I allowed MacOS to send the crash report >>> to Apple. >>> >> This might require further investigation of the specific notebook you're >> working with. I suggest starting a dialog with technical support >> about this. >> > OK. If I can reproduce the problem. I assume that Tech Support can > access Mathematica crash logs sent to Apple. Not a safe assumption. I don't know as much about Apple's mechanism, but I know that Microsoft prevents developers from being able to correlate crash reports with specific users as a means of protecting privacy. I'll bet Apple does something similar. Sincerely, John Fultz jfultz at wolfram.com User Interface Group Wolfram Research, Inc. > I bet the logs are under a > rock somewhere on my machine somewhere as well. > > Regards, > > Joe Gwinn