import bpy import bgl import blf def draw_callback_px(self, context): print("mouse points", len(self.mouse_path)) font_id = 0 # XXX, need to find out how best to get this. # draw some text blf.position(font_id, 15, 30, 0) blf.size(font_id, 20, 72) blf.draw(font_id, "Hello Word " + str(len(self.mouse_path))) # 50% alpha, 2 pixel width line bgl.glEnable(bgl.GL_BLEND) bgl.glColor4f(0.0, 0.0, 0.0, 0.5) bgl.glLineWidth(2) bgl.glBegin(bgl.GL_LINE_STRIP) for x, y in self.mouse_path: bgl.glVertex2i(x, y) bgl.glEnd() # restore opengl defaults bgl.glLineWidth(1) bgl.glDisable(bgl.GL_BLEND) bgl.glColor4f(0.0, 0.0, 0.0, 1.0) class ModalDrawOperator(bpy.types.Operator): """Draw a line with the mouse""" bl_idname = "view3d.modal_operator" bl_label = "Simple Modal View3D Operator" def modal(self, context, event): context.area.tag_redraw() if event.type == 'MOUSEMOVE': self.mouse_path.append((event.mouse_region_x, event.mouse_region_y)) elif event.type == 'LEFTMOUSE': context.region.callback_remove(self._handle) return {'FINISHED'} elif event.type in {'RIGHTMOUSE', 'ESC'}: context.region.callback_remove(self._handle) return {'CANCELLED'} return {'RUNNING_MODAL'} def invoke(self, context, event): if context.area.type == 'VIEW_3D': context.window_manager.modal_handler_add(self) # Add the region OpenGL drawing callback # draw in view space with 'POST_VIEW' and 'PRE_VIEW' self._handle = context.region.callback_add(draw_callback_px, (self, context), 'POST_PIXEL') self.mouse_path = [] return {'RUNNING_MODAL'} else: self.report({'WARNING'}, "View3D not found, cannot run operator") return {'CANCELLED'} def register(): bpy.utils.register_class(ModalDrawOperator) def unregister(): bpy.utils.unregister_class(ModalDrawOperator) if __name__ == "__main__": register()