ipkiss 3.12版加入write_obj函数，可以直接输出器件的三维模型。

如，输出自定义的mmi的三维模型：

代码如下：

from si_fab import all as pdk
from ipkiss3 import all as i3class MMI1x2(i3.PCell):"""MMI with 1 input and 2 outputs."""_name_prefix = "MMI1x2"trace_template = i3.TraceTemplateProperty(doc="Trace template of the access waveguide")width = i3.PositiveNumberProperty(default=4.0, doc="Width of the MMI section.")length = i3.PositiveNumberProperty(default=20.0, doc="Length of the MMI secion.")taper_width = i3.PositiveNumberProperty(default=1.0, doc="Width of the taper.")taper_length = i3.PositiveNumberProperty(default=5.0, doc="Length of the taper")waveguide_spacing = i3.PositiveNumberProperty(default=2.0, doc="Spacing between the waveguides.")def _default_trace_template(self):return pdk.SiWireWaveguideTemplate()class Layout(i3.LayoutView):def _generate_elements(self, elems):length = self.lengthwidth = self.widthtaper_length = self.taper_lengthtaper_width = self.taper_widthhalf_waveguide_spacing = 0.5 * self.waveguide_spacingcore_layer = self.trace_template.core_layercladding_layer = self.trace_template.cladding_layercore_width = self.trace_template.core_width# Si coreelems += i3.Rectangle(layer=core_layer,center=(0.5 * length, 0.0),box_size=(length, width),)elems += i3.Wedge(layer=core_layer,begin_coord=(-taper_length, 0.0),end_coord=(0.0, 0.0),begin_width=core_width,end_width=taper_width,)elems += i3.Wedge(layer=core_layer,begin_coord=(length, half_waveguide_spacing),end_coord=(length + taper_length, half_waveguide_spacing),begin_width=taper_width,end_width=core_width,)elems += i3.Wedge(layer=core_layer,begin_coord=(length, -half_waveguide_spacing),end_coord=(length + taper_length, -half_waveguide_spacing),begin_width=taper_width,end_width=core_width,)# Claddingelems += i3.Rectangle(layer=cladding_layer,center=(0.5 * length, 0.0),box_size=(length + 2 * taper_length, width + 2.0),)return elemsdef _generate_ports(self, ports):length = self.lengthtaper_length = self.taper_lengthtrace_template = self.trace_templatehalf_waveguide_spacing = 0.5 * self.waveguide_spacingports += i3.OpticalPort(name="in1",position=(-taper_length, 0.0),angle=180.0,trace_template=trace_template,)ports += i3.OpticalPort(name="out1",position=(length + taper_length, -half_waveguide_spacing),angle=0.0,trace_template=trace_template,)ports += i3.OpticalPort(name="out2",position=(length + taper_length, half_waveguide_spacing),angle=0.0,trace_template=trace_template,)return portsclass Netlist(i3.NetlistFromLayout):passif __name__ == '__main__':mmi_layout = MMI1x2().Layout()mmi_layout.visualize(annotate=True)mmi_geometry = i3.device_sim.SimulationGeometry(layout=mmi_layout,process_flow=i3.TECH.VFABRICATION.PROCESS_FLOW,)mmi_geometry.write_obj(filename="mmi.obj")

输出三维模型部分的代码：

mmi_geometry = i3.device_sim.SimulationGeometry(layout=mmi_layout,process_flow=i3.TECH.VFABRICATION.PROCESS_FLOW,)mmi_geometry.write_obj(filename="mmi.obj")

生成的obj文件可以用Mayo打开。