Different materials for top and bottom decks.

Author: yufei4hua

drone_models/data/cf21B_500.xml

@@ -8,7 +8,9 @@
     <material name="silver" rgba="0.898 0.898 0.898 1"/>
     <material name="gold" rgba="0.969 0.878 0.6 1"/>
     <material name="green" rgba="0.522 0.902 0.145 1"/>
-    <material name="clear" rgba="1.0 1.0 1.0 0.0"/>
+    <!-- The LED materials are initially transparent and can be changed dynamically -->
+    <material name="led_top" rgba="1.0 1.0 1.0 0.0"/>
+    <material name="led_bot" rgba="1.0 1.0 1.0 0.0"/>
 
     <mesh name="pcb" file="cf21B/cf21B_pcb.stl" scale="1e-3 1e-3 1e-3"/>
     <mesh name="motors" file="cf21B/cf21B_motors.stl" scale="1e-3 1e-3 1e-3"/>
@@ -47,8 +49,8 @@
       <geom mesh="connector-pins" material="gold" class="visual" />
       <geom mesh="battery" material="light-gray" class="visual" />
       <geom mesh="battery-holder" material="black" class="visual" />
-      <geom name="led_top" mesh="led-diffusor" material="clear" class="visual" pos="0 0 0.015"/>
-      <geom name="led_bot" mesh="led-diffusor" material="clear" class="visual" pos="0 0 -0.002" euler="180 0 0"/>
+      <geom name="led_top" mesh="led-diffusor" material="led_top" class="visual" pos="0 0 0.015"/>
+      <geom name="led_bot" mesh="led-diffusor" material="led_bot" class="visual" pos="0 0 -0.002" euler="180 0 0"/>
 
       <!-- Collision geometry is estimated based on the visual mesh. We use a sphere for maximum
        computational efficiency with larger swarms. Used by default-->