[Mesa-dev] Gallium3D and Glide

[Brian Paul]

On 03/01/2011 09:51 AM, Roland Scheidegger wrote:
> Am 01.03.2011 16:23, schrieb Brian Paul:
>> On 03/01/2011 04:18 AM, Blaž Tomažič wrote:
>>> On Mon, 2011-02-28 at 16:39 -0800, Brian Paul wrote:
>>>> On Mon, Feb 28, 2011 at 4:13 PM, Blaž Tomažič<blaz.tomazic at gmail.com>   wrote:
>>>>> Hi Mesa developers,
>>>>>
>>>>> I am really interested in Gallium3D and I'm thinking about a project for
>>>>> my diploma (I think this is the same as bachelor's degree) on a computer
>>>>> university. I'm thinking about writing a Glide state tracker for
>>>>> Gallium3D. I know that Glide hasn't been used for a decade, but I think
>>>>> it would be relatively "easy" to implement an old 3D API and a great way
>>>>> to learn a part of Gallium3D on the way.
>>>>>
>>>>> Some old games (only Glide: Need for Speed 2; Glide and OpenGL: Unreal,
>>>>> Quake 2) used Glide API for rendering and Gallium3D could therefore
>>>>> accelerate them on newer hardware and more importantly, render them with
>>>>> nicer graphics instead of software rendering as is with some glide only
>>>>> games. I don't know if there were any Linux games, but Gallium3D works
>>>>> on Windows too if I'm not mistaken.
>>>>>
>>>>> So I have a few question for you:
>>>>>    - How hard and how much work would be involved in implementing such an
>>>>> API? (Any help on implementing it would be welcomed and appreciated of
>>>>> course)
>>>>>    - Are Glide to OpenGL wrappers a better solution because of changing
>>>>> nature of Gallium3D interface? (Personally I think they are, but I would
>>>>> like to work directly on Gallium)
>>>>>    - Do you think this project would fit well in Gallium3D or do you have
>>>>> any other/better proposals for a project including Gallium3D?
>>>>
>>>> I don't mean to discourage you, but I this probably wouldn't be a very
>>>> good project.
>>>>
>>>> The Glide API and 3dfx hardware is lacking in a number of areas,
>>>> particularly shaders.  Gallium was intended for newer hardware so it
>>>> wouldn't be a good fit for this older technology.
>>>>
>>>> I'm sure there are other projects you could do related to
>>>> OpenGL/gallium if that's where your interest lies.  Other people on
>>>> this list might have some ideas.  I could probably come up with a few
>>>> otherwise.  What do you think?
>>>>
>>>> -Brian
>>>
>>> I know that Glide is an old technology and probably I should test this
>>> games if they even run on newer OSs. But still, Gallium supports OpenGL
>>> 1.x functionality and Glide is a subset of it. Fixed-pipe  functionality
>>> is easily implemented with shaders so I think that it could be
>>> implemented.
>>
>> The issue isn't converting fixed-function GL rendering (e.g. 1.x
>> functionality) into shaders, it's converting Gallium shaders into
>> Glide/3dfx fixed-function.
>
> But he was only talking about implementing a glide state tracker hence I
> can't see why he'd need to do that.

Oops, I misread the email.  I thought Blaz was proposing a glide 
driver, not a state tracker.


> So I think conceptually this would work just fine.
> Still, it might not be something terribly useful. For one, if you'd want
> to run this with windows, while gallium is OS-independent, the hw
> drivers surely are not. Hence you'd also need to write a d3d or ogl
> backend driver for gallium if you'd want it to run hw-accelerated with
> windows. Also, for this really old glide api, opengl wrappers are
> probably just fine - noone is going to write new glide apps anyway.

Agreed.

-Brian