Rust+cgmathで変換行列を計算

[package]
name = "opengltest"
version = "0.1.0"
edition = "2021"


[dependencies]
glutin = "0.26.0"
gl="0.14.0"

cgmath = "0.18.0"

pub fn draw_triangle(programid:gl::types::GLuint,vertexbuffer: gl::types::GLuint,colorbuffer:gl::types::GLuint){

    unsafe {
        gl::UseProgram(programid);
    }


    let translate_mat = cgmath::Matrix4::from_translation(
        cgmath::Vector3::new(0.0,0.0,-3.0)
    );
    let rotate_mat = cgmath::Matrix4::from_angle_z(cgmath::Deg(45.0));

    let model_mat = rotate_mat * translate_mat;

    let fov = cgmath::Deg(45.0);
    let aspect = 1.0;
    let near = 0.1;
    let far = 100.0;
    let proj_mat = cgmath::perspective(fov,aspect,near,far);


    let proj;
    let model;
    unsafe {
        let proj_location_name = CString::new("projectionMatrix").unwrap();
        let model_location_name = CString::new("modelViewMatrix").unwrap();
        proj = gl::GetUniformLocation(programid,proj_location_name.as_ptr());
        model = gl::GetUniformLocation(programid,model_location_name.as_ptr());

        gl::UniformMatrix4fv(proj,1,gl::FALSE,proj_mat.as_ptr());
        gl::UniformMatrix4fv(model,1,gl::FALSE,model_mat.as_ptr());
    }
/*
    // デバッグ
    println!("proj location: {}",proj);
    println!("model location: {}",model);
*/

    unsafe{
        gl::EnableVertexAttribArray(0);
        gl::BindBuffer(gl::ARRAY_BUFFER,vertexbuffer);
        gl::VertexAttribPointer(
            0,
            3,
            gl::FLOAT,
            gl::FALSE,
            0,
            null()
        );
    }

    unsafe{
        gl::EnableVertexAttribArray(1);
        gl::BindBuffer(gl::ARRAY_BUFFER,colorbuffer);
        gl::VertexAttribPointer(
            1,
            3,
            gl::FLOAT,
            gl::FALSE,
            0,
            null()
        );
    }

    unsafe {
        gl::DrawArrays(gl::TRIANGLES, 0,3);

        let err_check = gl::GetError();
        if err_check != gl::NO_ERROR {
            println!("ERROR::: {}\n", err_check);
        }

        gl::DisableVertexAttribArray(0);
        gl::DisableVertexAttribArray(1);
    }

    unsafe {
        gl::UseProgram(0);
    }

}