HiRISE DEM's Options

[JRA]

Hi all, I've finally had enough free time to do some more animations based on the HiRISE DTMs. I hope you like them.

Absolutely amazing. I love your animations. I do have a question if you don't mind. How do you handle the large .25m images and in real time no less? Do you chop them up into more manageable pieces? Or do you just have a really powerful computer/graphics card? I've been using 3dsmax and it really doesn't like large images, so I have to chop mine up into small bits, which can be a bit of a pain. I'm just wondering if you have a better technique or solution.

Thanks.

[Mars3D]

Hi JRA,
I have 4GB of ram (only 3GB is usable because I'm running a 32bit OS) The maximum image size I have been able to load into system memory is 32768x49152. Because its greyscale it uses 32768x49152x1 bytes which is 1.6GB. The image is then broken into tiles in memory and a cache of visible tiles are stored on the graphics card, so although I have a graphics card with 1.5Gb of RAM I think 512MB of video RAM would work ok to.

Some of the dataset images are bigger than what I can load into system memory e.g. Mojave, so I have to crop them. A 64bit OS with 6GB of RAM would allow me to not crop any of the datasets and run at the maximum resolution.

I am using a dual core CPU @ 1.8Ghz, CPU speed is not a limiting factor and mid range GPUs can handle the number of polygons I'm rendering. The biggest issue is the high system memory requirement.

I don't know 3dsmax so I cant give you any advice on that.

[JRA]

Hey, thanks for the reply and information. I think I'll have to stick to chopping them up into bite sized pieces for now then.