Which GPUs are we going to support?

Jack Claw was in development between 2006-2008 and was released in the Humble Frozenbyte Bundle for the community to play and build upon.
alt_turo
Posts: 195
Joined: Mon Dec 13, 2010 11:06 am

Which GPUs are we going to support?

Postby alt_turo » Thu May 26, 2011 2:05 pm

Currently we support theoretically anything with Shader Model 2.0. On Direct3d there's some support for even older shader models. In practice some older Intels work slightly poorly and it's been a long time since anyone tested with shader model 1.1 or 1.4 GPUs.

What GPUs do we want to support? Things to consider:

On OpenGL we currently use EXT_framebuffer_object. There is a new extension ARB_framebuffer_object which is better.

EXT_framebuffer_object:
1. Is older
2. There are no guaranteed supported FBO formats like in the ARB extension. This would cause some pain in our FBO initialization code and if we're not very careful can lead to nonfunctioning game on a theoretically supported GPU.
3. This extensions does not allow color and depth/stencil buffers to be different sizes. Direct3D and ARB extension do. This is BAD. Because of this there are some REALLY ugly hacks in the current OpenGL renderer.

ARB_framebuffer_object:
1. Is newer and also part of OpenGL 3.0 spec
2. Gets rid of points 2 and 3 above
3. Last time I checked the latest Nvidia binary driver available for GeForce 5 series did not include this extension. People with this hardware would be unable to run OpenGL versions even though their GPUs might support all other features and run in Direct3D mode.


Which shader model are we going to require?
On Direct3D 1.1 and 1.4 might be supported but it's very messy and I'd like to get rid of it. On Opengl SM 2.0 is required because the older shader extensions are very messy.

SM 2.0 has some limitations on shader length/complexity. If we add some advanced effects we might need 3.0. Do we leave people with only SM 2.0 hanging or add backwards-compatibility stuff?
Turo Lamminen
Alternative Games

User avatar
Urfoex
Posts: 50
Joined: Fri Apr 15, 2011 11:14 am

Re: Which GPUs are we going to support?

Postby Urfoex » Wed Jun 01, 2011 6:36 pm

I would like to see some higher and newer qualities so OpenGL 3.3 with GLSL 3.3 FTW! 8)
+-----------------------------------------------------------------\
| Debian testing 64Bit on
| * AMD Phenom x4 905e (4x2500Mhz)
| * 6GB Ram
| * AMD/ATI Radeon HD4770 (fglrx)
+-----------------------------------------------------------------/

alt_turo
Posts: 195
Joined: Mon Dec 13, 2010 11:06 am

Re: Which GPUs are we going to support?

Postby alt_turo » Fri Jun 03, 2011 1:18 pm

Urfoex wrote:I would like to see some higher and newer qualities so OpenGL 3.3 with GLSL 3.3 FTW! 8)

That doesn't mean we have to drop support for old GPUs. OpenGL is nice like that. However if we then want to get parity on Direct3D side someone would have to add a Direct3D 10 renderer. Direct3D is nasty like that.
Turo Lamminen
Alternative Games


Return to “Jack Claw Feedback & Development”

Who is online

Users browsing this forum: No registered users and 1 guest