Kaba class Renderer ed

class Renderer
    var command_buffers: owned[CommandBuffer][]
    var device: Device&
    var height: i32
    var image_available_semaphore: owned[Semaphore]
    var pool: owned[DescriptorPool]
    var render_finished_semaphore: owned[Semaphore]
    var wait_for_frame_fences: owned[Fence][]
    var width: i32

    # constructors
    func mut __init__(_device: Device&)

    # functions
    func area() -> rect
    func virtual current_command_buffer() -> CommandBuffer*
    func virtual current_frame_buffer() -> FrameBuffer*
    func virtual default_render_pass() -> RenderPass*
    func mut virtual end_frame()
    func mut virtual start_frame() -> bool