For both Mark and Chris, Yes, compile() may do that in some cases. However, from my very own experience, in many cases it fails to accurately detect what can be merged. Besides that, there are two specific cases that I want to explain:
1. the merging is completely governed by the permissions the user is adding to the scene elements. In most of the cases, the user simply assigns permissions by default, thus totaly defeating the compile() purpose - compile() works only if you don't set any permissions at all. 2. the merging is not done at geometry level, but at scene elements level. An example, let's consider a scene containing 100 spheres, each in it's own TransformGroup containing a different Transform3D. The compile() will *NOT* transform that into a *single* Geometry object, but *you* can do it ! I know that 2. is true, because at the very first stage of my project, I was relying too much on the compile() method. The scene graph was following the hierarchical model description, which was very convenient. However, I saw poor performance and a huge memory usage, besides the fact that compile()-ing or not didn't change anything visible in the performance. Later on I've spend a lot of effort to analize the model I was importing, up to the level of individual triangles and merge everything that I can *before* even generating the Geometry objects. Yes, I've applyied the transforms directly to the vertexes of the triangles and moved the triangles one level up in the hierarchy. Combining that with factory objects to detect and reuse Geometry objects that was repeated, reuse Appearances and Appearances elements, so the overall result was an increase of performance in terms of fps to over 100% (double the fps) and a reduction in memory usage from 200-300 MB to less than 70 MB. Cheers, Florin -----Original Message----- From: Discussion list for Java 3D API [mailto:[EMAIL PROTECTED] Behalf Of Mark McKay Sent: Mittwoch, 5. Mai 2004 21:46 To: [EMAIL PROTECTED] Subject: Re: [JAVA3D] the Need for Speed debate Florin Herinean wrote: >here are my 2c: > >1) carefully design your scene. Don't use TransformGroups if you don't plan >to dynamically move the objects bellow. A static branch containing many >TransformGroups is a waste of resources which results in poor performance >and a high memory usage. Collapse whenever possible such static branchgroups >to Shape3D's or, if possible to single geometries. > > > I thought compiling a scene would walk the scene graph and eliminate unnecessary Transform groups, and even go as far as to merge a static tree into a single Shape. Am I wrong in this? Mark McKay -- http://www.kitfox.com =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help". =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
