Meeting Minimum Requirements and the definition

[Accelerator]

First thing: For some strange reason, most OpenGL games requiring hardware T&L run on GPUs without it. Why this is I just do not know. How well they run is another question though. As for having shared memory, this isn't really a problem because I've seen KOTOR 1 and 2 being played just fine on my cousin's computer with an nForce motherboard which has an onboard GeForce2 MX which has some 32MB of shared memory.

 

The problem is in the features, the Radeon Xpress 200M will not perform well in KOTOR because KOTOR 1 and 2 are vertex sensitive. The KOTOR engine has very complex vertex shaders and also some cool fragment programs.

 

The KOTOR engine depends on three things:

 

1) Fragment program/register combiner/Pixel Shader support (i.e. GeForce2 MX or better, Radeon 8500 or better. If this had been a D3D game, it would have been Radeon 7500, but hey )

 

2) Vertex shader support (Some Vertex shaders are too large to entirely fit in hardware on graphics cards like Radeon 8500/9000 or GeForce2 series. In such cases vertex shader features are to be emulated on the CPU causing CPU strain)

 

3) Hardware T&L for geometry related operations

 

KOTOR engine has two separate render paths for NVIDIA and ATI graphics cards. The ATI path apparently looks prettier overall while the NVIDIA path runs faster due to various hardware-specific tweaks made available via OpenGL being used in the engine.

 

When your graphics card does not support register combiners (i.e. Radeon 7500 and below, Riva TNT2 and below), then it will suffer badly because it will run the slowest render path available.

 

Therefore, KOTOR performance depends on:

 

1) whether the graphics card supports per-pixel shading (i.e. GeForce2/Radeon 8500 or better)

2) Vertex Shader support

3) Hardware T&L

4) CPU speed

 

For example, a GeForce2 MX card running on a 2.2GHz CPU will be running most vertex shaders in software emulation (i.e. performing vertex shader operations on CPU) because GeForce2 series does not support vertex shaders. But a GeForce2 will still perform well because the CPU speed is quite high, and the GeForce2 supports per-pixel shading as well as Hardware T&L. The same applies to GeForce4 MX, which will be slightly better because of limited hardware vertex shader support under OpenGL, and the Radeon 8500/9000 series, which can perform some, but not all of the vertex shader programs in hardware.

 

Read here for more detailed info, it pertains to the Mac version but the engine would probably largely remain the same:

http://www.insidemacgames.com/news/story.php?ArticleID=9934

 

The problem with integrated chipsets is that KOTOR will detect hardware pixel and vertex shader support, but since Vertex shaders and T&L are done in software over the CPU anyway (though KOTOR thinks the chipset has hardware support for these functions), there is no performance improvement. So, if someone wants to play KOTOR on these PCs, their CPU will be under heavy strain due to which the CPU will need to be of a VERY FAST speed if the person intends to play it smoothly. The vertex shaders and hardware T&L support are the primary reason why KOTOR runs slow on most integrated GPUs. Shared memory has little to do with anything, because if the graphics card already has the features needed to run a game with FULL HARDWARE ACCELERATION, and after sharing, enough memory is left to fulfil the requirements of the game, the game (KOTOR) should run perfectly.

Edited May 17, 2007 by Accelerator