Function postprocess

examples/cuda/gpu/path_tracer_gpu/src/render_kernels.rs:41–56

(fb: *const Vec3, out: *mut vek::Vec3<u8>, view: Viewport)

/// Postprocesses a (scaled) buffer into a final u8 buffer.
#[kernel]
pub unsafe fn postprocess(fb: *const Vec3, out: *mut vek::Vec3<u8>, view: Viewport) {
    let idx_2d = thread::index_2d();
    if idx_2d.x >= view.bounds.x as u32 || idx_2d.y >= view.bounds.y as u32 {
        return;
    }
    let idx = idx_2d.y as usize * view.bounds.x + idx_2d.x as usize;
    let original = &*fb.add(idx);
    let out = &mut *out.add(idx);
    // gamma=2.0
    let gamma_corrected = original.sqrt();

    *out = (gamma_corrected * 255.0)
        .clamped(Vec3::zero(), Vec3::broadcast(255.0))
        .numcast()
        .unwrap();
}