Function look_at_rh

tools/imposter-baker/src/render.rs:454–464

(eye: [f32; 3], target: [f32; 3], up: [f32; 3])

fn dot3(a: [f32; 3], b: [f32; 3]) -> f32 { a[0]*b[0] + a[1]*b[1] + a[2]*b[2] }

fn look_at_rh(eye: [f32; 3], target: [f32; 3], up: [f32; 3]) -> [[f32; 4]; 4] {
    let f = normalize3([target[0] - eye[0], target[1] - eye[1], target[2] - eye[2]]);
    let s = normalize3(cross(f, up));
    let u = cross(s, f);
    [
        [ s[0],  u[0], -f[0], 0.0],
        [ s[1],  u[1], -f[1], 0.0],
        [ s[2],  u[2], -f[2], 0.0],
        [-dot3(s, eye), -dot3(u, eye), dot3(f, eye), 1.0],
    ]
}

fn ortho_rh(l: f32, r: f32, b: f32, t: f32, n: f32, f: f32) -> [[f32; 4]; 4] {
    // wgpu clip-space Z = [0, 1].