import bpy
import bgl
import blf
import time
def draw_callback_px(self, context):
font_id = 0
# draw some text
blf.position(font_id, 15, 30, 0)
blf.size(font_id, 20, 72)
blf.draw(font_id, str(time.time()))
# 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 ModalOperator(bpy.types.Operator):
bl_idname = "object.modal_operator"
bl_label = "Simple Modal Operator"
timer = None
draw_handle = None
def modal(self, context, event):
context.area.tag_redraw()
if event.type in {'RIGHTMOUSE', 'ESC'}:
print("CANCELLED")
context.window_manager.event_timer_remove(self.timer)
bpy.types.SpaceView3D.draw_handler_remove(self.draw_handle, 'WINDOW')
return {'CANCELLED'}
if event.type == "TIMER":
print(time.time())
return {'PASS_THROUGH'}
def invoke(self, context, event):
self.timer = context.window_manager.event_timer_add(0.1, context.window)
self.draw_handle = bpy.types.SpaceView3D.draw_handler_add(draw_callback_px, (self, context), 'WINDOW', 'POST_PIXEL')
context.window_manager.modal_handler_add(self)
print("INVOKE")
return {'RUNNING_MODAL'}
if __name__ == "__main__":
bpy.utils.register_class(ModalOperator)
bpy.ops.object.modal_operator('INVOKE_DEFAULT')
As you can see in the code, the console is updated normally as event.type == “TIMER”. But unfortunately the draw handler is updated only when a user input event occurs.
Not even putting the tag_redraw() inside the TIMER condition helps.
Do you know how is it done?
There is not documentation about this.
https://www.blender.org/api/blender_python_api_2_77_0/bpy.types.Space.html?highlight=draw_handler_add#bpy.types.Space.draw_handler_add
