Use glium ?

[Yamakaky]

As you use opengl, you should check https://github.com/tomaka/glium/.

[simias]

I considered it but it's basically the first time I'm using OpenGL so I wanted to understand how the "raw" API worked.

I was also concerned about instabilities in glium: I started working on this emulator before rust itself was stabilized, just fixing breakage with rust-nightly and rust-sdl2 was a daily ordeal, I didn't want to add another experimental dependency. That might be less of an issue now though.

Keep in mind that the current renderer is mostly placeholder code, it doesn't handle textures or transparency. When I revisit the GPU I'll consider switching to glium if it supports everything I need to emulate the PlayStation's GPU accurately (which includes some uses cases not commonly seen in the average 3D application I think).

[Yamakaky]

Some simplifications such a migration would do:

• remove error.rs: glium does it better with less overhead.
• VertexBuffer replaces buffer.rs (check the persistent and write methods.
• replace shader.rs by https://tomaka.github.io/glium/glium/struct.Program.html#method.from_source
• mod.rs: removes drop, simplifies new, use standard rust types instead of GL*, replace draw with VertexBuffer::write
• remove all unsafe blocks!

Some pointers:

• https://medium.com/@tomaka/the-glium-library-5be149d87dc1#.8ta0w9de5
• https://github.com/tomaka/glium/
• glutin doesn't support controllers for now so https://github.com/AngryLawyer/rust-sdl2 (minimal changes).

[Yamakaky]

BTW, glMemoryBarrier calls are automatic https://tomaka.github.io/glium/glium/

[simias]

I've talked with @tomaka a while ago and he told me that some of the things that are needed by rustation's renderer aren't yet supported fully by glium (mainly using a texture while simultaneously rendering into it if memory serves).

That being said it would probably be better to improve glium rather than reinventing the wheel. Once again my main reason for using raw OpenGL was to get a feel for it. Now that I've seen how it looks like I think I would welcome the glium abstraction with my arms wide open...

If you want to try and port the current code to glium I'll definitely attempt to merge it in but keep in mind that the current renderer is basically placeholder code, see issue #10 for my current "specification" for the OpenGL renderer.

If you feel ambitious and want to try to implement a more fully featured renderer (in glium or otherwise) I'd gladly help you but at the moment I can't boot a single game correctly (although I think I'm getting close...) so it might not be great for testing.

[Yamakaky]

A few questions:

• I plan to pack the color and position of the vertices in a struct like https://github.com/tomaka/glium/blob/master/examples/triangle.rs. Currently they are separated indifferent buffers. Is it possible ?

[simias]

Definitely, I considered doing it but I thought it would be a pain to match the rust representation with the shader one, if glium does it for us then let's go for it. Eventually we'll probably have to add new attributes for textures, transparency etc...

[simias]

By the way I hang on the freenode IRC network if you want a more immediate communication medium. I could also create a gitter for the project or something like that, whatever's the most convenient.

[Yamakaky]

Ok then. It's easy with glium.