Kaba class Context ed

class Context
    var default_framebuffer: FrameBuffer&
    var default_shader_2d: Shader&
    var default_shader_3d: Shader&
    var extensions: string[]
    var gl_renderer: string
    var gl_version: string
    var glsl_version: string
    var tex_white: Texture&
    var vb_temp: VertexBuffer&
    var vb_temp_i: VertexBuffer&

    # constructors
    func mut __init__()

    # functions
    func mut create_shader(source: string) -> xfer[Shader]
    func mut load_shader(filename: Path) -> xfer[Shader]