Somewhat unrelated perhaps... Some time ago I prepared three somewhat identical image files, composite aerial photographs, about 6 x 8.5 km coverage, 100 dpi gave 11MB image 3312 x 4681 pixels 150 dpi gave 18MB image 4967 x 7021 pixels 300 dpi gave 51MB image 9934 x 14042 pixels All but the smallest exceed the 4096 limit. These resulted in similar sized loch files. They all take a reasonable time to load, no errors produced. The interesting thing is that the 50MB one produces a model as black as the inside of Hotblack Deseartos spaceship. Ie nothing is displayed, not even the grey terrain model. Some sort of overload, or too much scaling perhaps? (Any caves imported over top of this are displayed correctly however -viewed just now with 5.3.1, it was created with whatever was current in Sept 2009). Maybe related to your file locations issue Wolfgang? Perhaps not? It would be nice to squeeze some more resolution out of Loch, but then I guess these 3D models are not necessarily suited to the detailed inspection or interrogation that a high resolution implies. Regards Bruce -----Original Message----- From: therion-bounces@speleo.sk [mailto:therion-bounces@speleo.sk] On Behalf Of Wolfgang Zillig Sent: Wednesday, 28 April 2010 7:48 a.m. To: therion@speleo.sk Subject: Re: [Therion] Loch: maximum resolution of image? Hello Stacho, thanks for your answer. Now I reduced the overlay image to 5000x5000 pixel. Still bigger than the 4096 but as I don't know GL_MAX_TEXTURE_SIZE it will be rescaled anyhow. File size is also smaller and it loads significantly faster. The question arose as I have access to a workstation with a quite good grafics card and if it would be possibe to use the full resolution... Anyhow the model looks nice now. I have another strange problem: the model gets loaded without surface texture (only gray height field) when I open the lox file on my external hard disk or from C:\temp. On the "desktop" it shows correct. Any idea? Best regards Wolfgang Am 27.04.2010 13:49, schrieb Stacho Mudrak:

Hi Wolfgang,

texture image size is limited by your hardware (GL_MAX_TEXTURE_SIZE variable returned by OpenGL) or 4096x4096 max. But if your input image is larger, it is scaled down. There is no limit on elevation model, but with some high density, there may be performance problems.

Best regards, S.

Quoting Wolfgang Zillig<wolfgang.zillig@web.de>:

...

Hi,

I once read somewhere that the overlay size is limited. Can anyone tell me where this limit is and where it could be changed (is it hard coded or hidden in a ini-file)? Is there something similar for the elevation model?

Many thanks Wolfgang _______________________________________________

The question arose as I have access to a workstation with a quite good grafics card and if it would be possibe to use the full resolution...

I am not sure, but on Win32 OpenGL supports just textures with sizes that are power of 2, so you would probably need graphic card that will be able to display texture size 8192x8192 (and to recompile loch, that is no problem). It would need some experimenting to adjust it in the code, I will have a look.

I have another strange problem: the model gets loaded without surface texture (only gray height field) when I open the lox file on my external hard disk or from C:\temp. On the "desktop" it shows correct. Any idea?

I have absolutly no idea. Regards, S.