Could I write customized shader for SWGL?

[kaiwk]

When use OpenGL, I can create shader like below:

mod shaders {
...
    pub static VERT_SHADER: &'static [u8] = b"#version 330 core

layout (location = 0) in vec3 position;

void main()
{
    gl_Position = vec4(position.x, position.y, position.z, 1.0);
}
\0";
...
}

...
    let vert_shader = gl.create_shader(gl::VERTEX_SHADER);
    gl.shader_source(vert_shader, &[shaders::VERT_SHADER]);
    gl.compile_shader(vert_shader);
...
    let program = gl.create_program();
    gl.attach_shader(program, vert_shader);
    gl.link_program(program);
    gl.use_program(program);

How to do that with swgl? Seems like swgl have its own syntax?

[kvark]

IIRC, SWGL translates our GLSL sources, so you should be able to have your custom shaders, as long as they do roughly the same or similar things to the existing shaders (or otherwise you might hit limitations of the implementation).

[kaiwk]

I can see prefix // shader: is used for debug, but if // shader: missing, shader_source will panic.

[kvark]

It was added for debugging purposes, and then SWGL decided to piggy back on it without adjusting the comment.
Maybe @lsalzman can chime in.

[kaiwk]

I can see that SWGL use glsl-to-cxx translating glsl to C/C++. It happens during compiling, and I thought I can translate glsl during runtime.

Maybe I can specify the shader_dir to my own directory.

[kaiwk]

I tried put the customized glsl in res directory, looks like SWGL doesn't support some new OpenGL API. I also find a bug of SWGL, see: #4325

[lsalzman]

I filed https://bugzilla.mozilla.org/show_bug.cgi?id=1703069 to fix this

We can close this now