Map screen coord to 3d scene with Vispy -

is there way of doing built in function?

i understand have revert transformation of projection screen. tried first obtaining simplified chain matrix with:

canvas.render_cs.node_transform(canvas.view.scene).simplified() , canvas.canvas_cs.node_transform(canvas.view.scene).simplified()

but lost here when both return chain object.

then tried canvas "node_transform" method:

canvas.render_cs.node_transform(canvas.view.scene).map((0, 0))

that gives result vector of 4 elements. thought coords of line, isn't.

here example code:

import sys vispy import app,scene  class canvas(scene.scenecanvas):     def __init__(self):         scene.scenecanvas.__init__(self, keys='interactive', show=true)          self.view = self.central_widget.add_view()         camera = scene.cameras.turntablecamera(fov=45, azimuth=80, parent=self.view.scene)          self.view.camera = camera         self.show()     def on_mouse_press(self, event):         """pan view based on change in mouse position."""         if event.button == 1:             x0, y0 = event.last_event.pos[0], event.last_event.pos[1]             x1, y1 = event.pos[0], event.pos[1]             print x1,y1             print self.view.scene.node_transform(self.canvas_cs).simplified()             print self.view.scene.node_transform(self.canvas_cs).map((x1,y1))  if __name__ == '__main__':     canvas = canvas()     axis = scene.visuals.xyzaxis(parent=canvas.view.scene)     if sys.flags.interactive != 1:         app.run()