lighttroupe/luz

class DirectorEffectCamera < DirectorEffect
    title                "Camera"
    description "Sets camera position, pitch, roll, yaw."

    hint "Place above effects that draw actors in the effects list."

    setting 'x', :float, :default => 0.0..1.0
    setting 'y', :float, :default => 0.0..1.0
    setting 'z', :float, :default => 0.0..1.0
    setting 'roll', :float, :default => 0.0..1.0
    setting 'pitch', :float, :default => 0.0..1.0
    setting 'yaw', :float, :default => 0.0..1.0

    setting 'width', :float, :range => 0.1..10.0, :default => 1.0..2.0
    setting 'height', :float, :range => 0.1..10.0, :default => 1.0..2.0

    def render
        if $env[:hit_test]
            # render nothing when hit testing
            yield

        elsif $env[:stage]
            yield

            # render a camera at its location
            GL.SaveMatrix {
                with_translation(x, y, z) {
                    with_pitch(pitch) {
                        with_yaw(yaw) {
                            with_roll(roll) {
                                with_scale(width, height) {
                                    draw_camera
                                }
                            }
                        }
                    }
                }
            }

        else
            # render via the camera
            GL.MatrixMode(GL::PROJECTION)
            GL.SaveMatrix {
                GLU.LookAt(
                    x, y, z,
                    x + (fuzzy_sine(-yaw + 0.5) - 0.5), y + (fuzzy_sine(-pitch + 0.5) - 0.5), -1,         # TODO: look at appropriate point
                    0, 1, 0)         # up vector positive Y up vector

                with_roll(-roll) {
                    GL.MatrixMode(GL::MODELVIEW)
                        with_scale(1.0/width, 1.0/height) {
                            yield
                        }
                    GL.MatrixMode(GL::PROJECTION)
                }
            }
            GL.MatrixMode(GL::MODELVIEW)
        end
    end

    def draw_camera
        far_z = 5
        half_height = 5.5 #* (height.to_f / width.to_f)
        half_width = 5.5 #* (height.to_f / width.to_f)

        # a unit square on the origin 0, 0, 0
        unit_square_outline

        @camera_distance_from_origin = 0.5
        GL.Begin(GL::LINES)
            GL.Vertex(0.0, 0.0, @camera_distance_from_origin) ; GL.Vertex(half_width, half_height, -far_z)
            GL.Vertex(0.0, 0.0, @camera_distance_from_origin) ; GL.Vertex(half_width, -half_height, -far_z)
            GL.Vertex(0.0, 0.0, @camera_distance_from_origin) ; GL.Vertex(-half_width, -half_height, -far_z)
            GL.Vertex(0.0, 0.0, @camera_distance_from_origin) ; GL.Vertex(-half_width, half_height, -far_z)
        GL.End

        GL.Begin(GL::LINE_LOOP)
            GL.Vertex(half_width, half_height, -far_z)
            GL.Vertex(half_width, -half_height, -far_z)
            GL.Vertex(-half_width, -half_height, -far_z)
            GL.Vertex(-half_width, half_height, -far_z)
        GL.End

        GL.Begin(GL::POINTS) ; GL.Vertex(0.0, 0.0, @camera_distance_from_origin) ; GL.End
    end
end