Hi, I was just wondering if it was possible to load and store textures into System memory instead of the video card memory? I know that system RAM is much slower than video RAM, but that''s not an issue in this case. I need to demonstrate my program on University computers, and I think that they only have 2MB of video memory!... Thanks for your time, Tin

Well sorry if this is not much help,but first of all I have to mention that the opengl programs that NeHe posts all almost all
small. I have even gotten so of them to run on my 75 Mhz machine!!!! If the University computers really slow you down as a last resort you Could bring your own PC to class

sorry if I wasted your time I just wanted to let you know that these progs do run on the low end machines!!!

Hey there, no problemo, no time wasted here...=P

I forgot to mention that my programs (not necessarily NeHe''s ones...) don''t run too good on my notebook either, which is a P3 500, but it only has 3Mb of video RAM...

I think that the performance lag is due to the lack of memory to store the textures into. My textures stretch off into the horizon!

I have used DirectX on a previous assignment (only 2D this time) and you could specify a "SYSTEM_MEMORY" flag on initialisation. Alas, the demo needs to work on WinNT 4.0, so D3D is out of the question...

Thanks for the pointer anyway =P

Tin

I think OpenGL will place your textures in the system memory (instead of video memory) once the video memory is exhausted. Make sure your university''s computers have video cards that support OpenGL, most low quality or old video cards don''t.


http://www.gdarchive.net/druidgames/

...well, the demo does actually RUN on the machines, but only at about 4/5 FPS!!, but when i switch onto wireframe mode, it shoots up to an acceptable 30FPS...does this mean that it does support OpenGL?

There are better machines on some of the other labs, and the demo looks pretty good on them, but typically, we have to be stuck in the lab with the crappest PCs...=P

Thanks anyway...

Tin

It could be that your school''s computers video cards don''t support OpenGL, and it is running in software mode. That would make it run very slowly, so 5 fps could actually be good for software mode...


http://www.gdarchive.net/druidgames/

what video chip do the computers have

http://members.xoom.com/myBollux

I don''t know of any graphics card with 2Mb that supports hardware accelerated OpenGL. Maybe some of the S3Virge cards with 2Mb have OpenGL drivers available, but in those cases you can hardly speak off acceleration...
I don''t know if you have to use OpenGL, but in software, I wouldn''t recommend it, since all OpenGL implementations must meet certain criteria, they aren''t very specific. So a software engine might be better in your case :/.

I''m not actually after hardware acceleration, after all, WinNT doesn''t even support it (right?).

There are some computers in the other labs that have 8mb Video cards (i think...) and the demo runs at a pretty good 50-60 fps. At home, I have a Radeon 64mb, and it runs at about 200fps in NT, and about 600fps in 98SE!!

Thank you all for your help, I think that I''ll just drag the tutor into one of the better labs for the demo!

Tin

quote: Original post by da_tinman

I''m not actually after hardware acceleration, after all, WinNT doesn''t even support it (right?).

WinNT fully supports OpenGL, as long as you can get good drivers for it to use your video card with. It doesn''t fully support DirectX is the problem (only up to version 5).

"Finger to spiritual emptiness underlying everything." -- How a C manual referred to a "pointer to void." --Things People Said
http://www.gdarchive.net/druidgames/