Re: [Visualpython-users] Arbitrary frame transformation routine

[Robert X. <nne...@gm...>]

I wrote a small frame wrapper class to add these sorts of transformations in
a program I developed:

class Frame(frame):
    def world_axes(self):
        x_axis = norm(self.axis)
        z_axis = norm(self.axis.cross(self.up))
        y_axis = norm(z_axis.cross(x_axis))
        return (x_axis, y_axis, z_axis)

    def world_offset(self, pos):
        x,y,z = self.world_axes()
        return pos.x*x + pos.y*y + pos.z*z

    def world_pos(self, pos):
        return self.pos + self.world_offset(pos)

    def frame_offset(self, pos):
        x,y,z = self.world_axes()
        return vector(pos.dot(x), pos.dot(y), pos.dot(z))

    def frame_pos(self, pos):
        return self.frame_offset(pos - self.pos)

world_pos is the frame->world transformation; frame_pos is the world->frame
transformation.

Robert