Hi Robert, OSG supports and displays RGB, RGB8 etc correctly, agreed. But whether it is "packing" the RGB components properly, I need to analyze. I think now we are deviating from my simple question that I asked initially. I again give a short description: I had originally 32 Bit textures. I wrote the geometry with the texture data to IVE file. The IVE file size was 26 MB. Then I realized that I do not need true color textures, so I converted my images to 8 Bit images (RGBA8) reducing my image size from 4 mb to 1 mb (This can be easily done using Paint.Net Free App). Then I again wrote the data to IVE file expecting that now the IVE file size shall be far less as the image data has reduced. But the file size is same 26 MB. Thus I guess OSG stores the texture data in RGB or RGBA format only and not in the original file format (that is RGB8 or RGBA8 unsigned byte in my case).
If I set RGBA8 in image->setInternalTextureFormat does not affect size or view. But if I set RGB in image->setPixelFormat instead of RGBA, I see 1 MB less size in the IVE file (now 25 MB). Maybe because now alpha componenet is not written. My final objective is if my texture sizes are less I should have more texture memory available in graphics memory to load additional textures. And i am trying to verify whether OSG loads OpenGL with actual texture size (in my case RGBA8) or uses always RGB/RGBA format only. The display anyway will not be affected but unnecessary texture memory will be allocated I guess. The discussion above is on OSG with OpenGL & not OSG with OpenGL ES. I am using OSG for our Simulation research & I do not doubt its capabilities. But since I am neither a novice nor a full expert in OSG I came across above doubts that someone in forum can answer/reply. Thank you! Cheers, umesh ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=62024#62024 _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
