From: Sven G. <sgo...@ja...> - 2000-05-02 07:01:41
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Jason Goh wrote: > > Hi again, > > I am wondering if the framerate of an OpenGL scene in a java applet is > comparatively slower than one using C++? > This is a perception i have while doing the programming for a web-enabled > OpenGL scene. :( > > Jason. Well - it depends :) On MS-Windows machines: MS-IE's JVM is much faster than Netscapes JVM :-( The resulting speed of MS-IE looks fine for me (play with the "use repaint" and "sleep" buttons on e.g. morph3D applet - remind, the default (using repaint & sleep) is safe for most JVM's ... but you can play with and customize it for diff. JVM/OS). Unix:Netscape's JVM is also quiet fast May be the Java2 PlugIn for Netscape is faster ?! I tested: Linux 2.3.99 pre6, XFree86 4.0 DRI (Vodoo3, 16bpp) gl-demo: gears native : 75-79 fps java2 & javacomp (inprise) (no repaint, no sleep -> max-fps): 78 fps Netscape (no repaint, no sleep -> max-fps): 58 fps So - the results looks acceptable ? YES ! AND the responsivenes of the native application (cursor keys to rotate) are not that nice, the java one is ! (Remember that the rotation-speed, is set slower in the java app. This is not the fps render speed) It depends on your OpenGL hardware acceleration also, of course. And - of course - Java IS slower than native code ! Well, all demos we have for GL4Java runs well with hardware acceleration, even the GLLandscapeWorld stuff, etc. Also: The usage of display lists is nearly as fast as the native usage ! Just the data generation/manipulation in java is, of course, slower than the native counterpart ! But you are right, we should create a fps measurement - and a kind of performance user guide and performance comparison between native and all the different java vms (incl. OS). So we can make a statement what we can expect ! Yours, Sven -- mailto:sgo...@ja... www : http://www.jausoft.com voice : +49-521-2399440, +49-170-2115963; fax: +49-521-2399442 |