Object occlusion issues with camera plugin for ROS

edit

I created two simple SDF models to represent a wall section and a door prop (that is, just a board with the picture of a door on it). When I place a "door" in front of a wall and get a camera (via the ROS camera plugin) to record the scene,

The door appears behind the wall in the camera image, even though it is clearly in front of it in the environment view.

However if I use the "Brick Box 3x1x3" from the model library instead of my own wall model, images are generated correctly:

What could be the problem here?

The wall SDF model and texture script are:

yumebros_room_wall_240cm2.sdf

<?xml version='1.0'?>
<sdf version="1.4">
  <model name='yumebros_room_wall_240cm2'>
    <static>true</static>
    <link name='link'>
      <pose>0 0 1.2 0 0 0</pose>
      <collision name='collision'>
        <geometry>
          <box>
            <size>0.2 2.4 2.4</size>
          </box>
        </geometry>
      </collision>
      <visual name='visual'>
        <geometry>
          <box>
            <size>0.2 2.4 2.4</size>
          </box>
        </geometry>
        <material>
          <script>
            <uri>model://yumebros_room_wall_240cm2/materials/scripts</uri>
            <uri>model://yumebros_room_wall_240cm2/materials/textures</uri>
            <name>Yumebros/RoomWallSurface</name>
          </script>
        </material>
      </visual>
    </link>
  </model>
</sdf>

white_paint.material

material Yumebros/RoomWallSurface
{
  technique
  {
    pass
    {
      texture_unit
      {
        texture white_paint.png
        scale 0.125 0.125
      }
    }
  }
}

And for the door:

yumebros_door_blue.sdf

<?xml version='1.0'?>
<sdf version="1.4">
  <model name='yumebros_door_blue'>
    <pose>0 0 1.05 0 0 0</pose>
    <static>1</static>
    <link name='link'>
      <collision name='collision'>
        <geometry>
          <box>
            <size>0.05 0.92 2.1</size>
          </box>
        </geometry>
      </collision>
      <visual name='visual'>
        <geometry>
          <box>
            <size>0.05 0.92 2.1</size>
          </box>
        </geometry>
        <material>
          <script>
            <uri>model://yumebros_door_blue/materials/scripts</uri>
            <uri>model://yumebros_door_blue/materials/textures</uri>
            <name>Yumebros/DoorBlue</name>
          </script>
        </material>
      </visual>
      <self_collide>1</self_collide>
      <gravity>1</gravity>
    </link>
  </model>
</sdf>

door_blue.material

material Yumebros/DoorBlue
{
  technique
  {
    pass
    {
      texture_unit
      {
        texture door_blue.png
      }
    }
  }
}