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Re: [LUG] Laptop for OpenGL

 

Robin,

Thanks for the info,

On 09/12/2011 22:25, Robin Cornelius wrote:
On Fri, Dec 9, 2011 at 8:48 PM, Chris Tipney<chris@xxxxxxxxxx>  wrote:

Ok so I'm not explaining this very well....

At the risk of displaying my ignorance,  why would I not want to use the
latest version of OpenGL? If so what version should I consider using and
what hardware does it need?

It's not a part of the course but I do need to be able to use OpenGL as part
of a final year project and at the moment this is far enough away to allow
me to get to grips with OpenGL before the 'rush' sets in...
Most of the updates to OpenGL effect the shader programming, and add
new features/new parts of the state you can do things, new things you
can access. The difference this makes is only really going to effect
you if you are pushing things to the limit and need top performance
out of the latest hardware. I would have thought everything you wanted
to do would be fine on a slightly older graphics card, anything open
GL 3.X or better should be fine. 2.X is probably getting a bit legacy
though.

Sounds like good advice - I'll see have a look to see which Nvidia cards work best with OpenGL 3.x and then find a suitable laptop. It may be that my old Thinkpad T43 will be OK but I need to change the fan (again) before I once more get that smell of overheated insulation :-)

What kinds of things are you looking to do with openGL? What sort of
data, how many verts/tris etc do you need to show?
I am looking to create a 'simple' 3D model of the human wrist and hand in block form - how detailed and how many verts/tris depends on how ambitious we get. The model has to move as in response to external commands. Initially I would be happy for the components to be blocks and cylinders.

I'm hoping that someone has already created one that I could use with permission since 'creating' the model is not the point of the exercise...



OpenGL functions DO NOT have to be in the gpu - often the driver will add
the support.

OK so why do they have a recommended minimum hardware requirement ?
Presumably it's better (as in faster) to get the GPU to do the work.

In general openGL functions are all implemented in the driver which
passes stuff directly out to the hardware unless you are using the
mesa "software" driver which does things 100% on the CPU. Thats what
you are doing with Vertex buffer objects, bound textures and shaders,
keeping data directly in the memory on the gfx card.  When you
implement shaders you run your code on the GPU to modify things
directly there, which is very fast and efficient.

Software OpenGL is not necessarily slow, someone i know runs a linux
VM (on windows host) using mesa open GL driver, and they get a
significantly better frame rate for identical setup than i do on my
laptops.
I can (and do) run Linux under VM on my new laptop so I would be interested to hear more about this option - is this a possibility?

Cheers,

Chris


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