bisect_handler.py

# B E W A R E 
#
# 1) requires a 3dview to be open


import bpy


sce = bpy.context.scene


def get_override():
    for window in bpy.context.window_manager.windows:
        screen = window.screen

        for area in screen.areas:
            if area.type == 'VIEW_3D':
                override = {'window': window, 'screen': screen, 'area': area}    
                return override


def my_handler(sce):
    
    sce.objects.active = bpy.data.objects['Alpha_0']
    
    co = (0.0, 0.0, 0.0) 
    no = (0.0, 0.0, 1.0)

    #    xstart=24, xend=223, ystart=506, yend=519)
    override = get_override()
    if override:
        bpy.ops.object.mode_set(override, mode='EDIT', toggle=False)
        bpy.ops.mesh.bisect('INVOKE_DEFAULT', plane_co=co, plane_no=no, clear_inner=True, clear_outer=True) 
        bpy.ops.object.mode_set(override, mode='OBJECT', toggle=False)
        
        bpy.ops.object.convert('INVOKE_DEFAULT', target='Curve')
        bpy.context.active_object.data.fill_mode = 'FULL'
        bpy.context.active_object.data.bevel_depth = 0.03
        # sce.update()   <-- crashes blender


def register():
    bpy.app.handlers.render_pre.append(my_handler)


register()