proc customSolverBias(self: Shape2D): float64 {.
gcsafe, locks: 0, raises: [], tags: []
.}

proc customSolverBias=(self: Shape2D; val: float64) {.
gcsafe, locks: 0, raises: [],
    tags: []
.}

proc collide(self: Shape2D; localXform: Transform2D; withShape: Shape2D;
            shapeXform: Transform2D): bool {.
gcsafe, locks: 0, raises: [], tags: []
.}

proc collideWithMotion(self: Shape2D; localXform: Transform2D; localMotion: Vector2;
                      withShape: Shape2D; shapeXform: Transform2D;
                      shapeMotion: Vector2): bool {.
gcsafe, locks: 0, raises: [],
    tags: []
.}

proc collideAndGetContacts(self: Shape2D; localXform: Transform2D;
                          withShape: Shape2D; shapeXform: Transform2D): Variant {.

    gcsafe, locks: 0, raises: [], tags: []
.}

proc collideWithMotionAndGetContacts(self: Shape2D; localXform: Transform2D;
                                    localMotion: Vector2; withShape: Shape2D;
                                    shapeXform: Transform2D; shapeMotion: Vector2): Variant {.

    gcsafe, locks: 0, raises: [], tags: []
.}