Adds a system which enables exporting occupancy grids.

BUILD.bazel

@@ -821,6 +821,26 @@ gz_sim_system_libraries(
     ],
 )
 
+gz_sim_system_libraries(
+    srcs = glob(
+        [
+            "src/systems/free_space_explorer/**/*.cc",
+            "src/systems/free_space_explorer/**/*.hh",
+        ],
+    ),
+    so_lib_name = "gz-sim-free-space_explorer--system.so",
+    static_lib_name = "gz-sim-free-space-explorer-system-static",
+    visibility = ["//visibility:public"],
+    deps = [
+        ":gz-sim",
+        "@gz-common//graphics",
+        "@gz-math",
+        "@gz-msgs//:gzmsgs_cc_proto",
+        "@gz-plugin//:register",
+        "@gz-transport",
+    ],
+)
+
 gz_sim_system_libraries(
     srcs = glob(
         [

examples/worlds/export_occupancy_grid.sdf

@@ -0,0 +1,183 @@
+<!--
+  This world demonstrates the FreeSpaceExplorer system plugin.
+  A lidar will explore the world and generate an occupancy grid.
+  The occupancy grid will be published as an image on the /scan_image topic.
+
+  To start the exploration, run the following command in a new terminal:
+  gz topic -t /start_exploration -m gz.msgs.Boolean -p 'data: true'
+-->
+<sdf version="1.6">
+  <world name="empty">
+    <gui>
+      <plugin filename="ImageDisplay" name="Image Display">
+        <topic>/scan_image</topic>
+      </plugin>
+    </gui>
+    <physics name="1ms" type="ignored">
+      <max_step_size>0.001</max_step_size>
+      <real_time_factor>1.0</real_time_factor>
+    </physics>
+    <plugin
+      filename="gz-sim-physics-system"
+      name="gz::sim::systems::Physics">
+    </plugin>
+    <plugin
+      filename="gz-sim-user-commands-system"
+      name="gz::sim::systems::UserCommands">
+    </plugin>
+    <plugin
+      filename="gz-sim-scene-broadcaster-system"
+      name="gz::sim::systems::SceneBroadcaster">
+    </plugin>
+    <plugin
+      filename="gz-sim-contact-system"
+      name="gz::sim::systems::Contact">
+    </plugin>
+    <plugin
+      filename="gz-sim-sensors-system"
+      name="gz::sim::systems::Sensors">
+      <render_engine>ogre2</render_engine>
+    </plugin>
+
+    <light type="directional" name="sun">
+      <cast_shadows>true</cast_shadows>
+      <pose>0 0 10 0 0 0</pose>
+      <diffuse>0.8 0.8 0.8 1</diffuse>
+      <specular>0.2 0.2 0.2 1</specular>
+      <attenuation>
+        <range>1000</range>
+        <constant>0.9</constant>
+        <linear>0.01</linear>
+        <quadratic>0.001</quadratic>
+      </attenuation>
+      <direction>-0.5 0.1 -0.9</direction>
+    </light>
+
+    <model name="model_with_lidar">
+        <pose>-1 -1 0.5 0 0 0</pose>
+        <link name="link">
+            <inertial>
+                <mass>0.1</mass>
+                <inertia>
+                <ixx>0.000166667</ixx>
+                <iyy>0.000166667</iyy>
+                <izz>0.000166667</izz>
+                </inertia>
+            </inertial>
+            <collision name="collision">
+                <geometry>
+                <box>
+                    <size>0.1 0.1 0.1</size>
+                </box>
+                </geometry>
+            </collision>
+            <visual name="visual">
+                <geometry>
+                <box>
+                    <size>0.1 0.1 0.1</size>
+                </box>
+                </geometry>
+            </visual>
+
+            <sensor name='gpu_lidar' type='gpu_lidar'>
+                <topic>scan</topic>
+                <update_rate>10</update_rate>
+                <lidar>
+                <scan>
+                    <horizontal>
+                    <samples>640</samples>
+                    <resolution>1</resolution>
+                    <min_angle>0</min_angle>
+                    <max_angle>6.28</max_angle>
+                    </horizontal>
+                </scan>
+                <range>
+                    <min>0.08</min>
+                    <max>9.0</max>
+                    <resolution>0.01</resolution>
+                </range>
+                </lidar>
+                <visualize>true</visualize>
+            </sensor>
+        </link>
+        <static>true</static>
+
+        <plugin
+            filename="gz-sim-free-space-explorer-system"
+            name="gz::sim::systems::FreeSpaceExplorer">
+            <lidar_topic>/scan</lidar_topic>
+            <image_topic>/scan_image</image_topic>
+            <start_topic>/start_exploration</start_topic>
+            <width>100</width>
+            <height>100</height>
+            <resolution>0.25</resolution>
+            <sensor_link>link</sensor_link>
+        </plugin>
+    </model>
+
+    <model name="cube">
+     <pose>1 1 0.5 0 0 0</pose>
+      <link name="box_link">
+        <inertial>
+          <inertia>
+            <ixx>0.16666</ixx>
+            <ixy>0</ixy>
+            <ixz>0</ixz>
+            <iyy>0.16666</iyy>
+            <iyz>0</iyz>
+            <izz>0.16666</izz>
+          </inertia>
+          <mass>1.0</mass>
+        </inertial>
+        <collision name="box_collision">
+          <geometry>
+            <box>
+              <size>1 1 1</size>
+            </box>
+          </geometry>
+        </collision>
+
+        <visual name="box_visual">
+          <geometry>
+            <box>
+              <size>1 1 1</size>
+            </box>
+          </geometry>
+          <material>
+            <ambient>1 0 0 1</ambient>
+            <diffuse>1 0 0 1</diffuse>
+            <specular>1 0 0 1</specular>
+          </material>
+        </visual>
+      </link>
+    </model>
+
+    <model name="ground_plane">
+      <static>true</static>
+      <link name="link">
+        <collision name="collision">
+          <geometry>
+            <plane>
+              <normal>0 0 1</normal>
+              <size>100 100</size>
+            </plane>
+          </geometry>
+        </collision>
+        <visual name="visual">
+          <geometry>
+            <plane>
+              <normal>0 0 1</normal>
+              <size>100 100</size>
+            </plane>
+          </geometry>
+          <material>
+            <ambient>0.8 0.8 0.8 1</ambient>
+            <diffuse>0.8 0.8 0.8 1</diffuse>
+            <specular>0.8 0.8 0.8 1</specular>
+          </material>
+        </visual>
+      </link>
+    </model>
+
+  </world>
+</sdf>

src/gui/plugins/CMakeLists.txt

@@ -149,14 +149,14 @@ add_subdirectory(playback_scrubber)
 add_subdirectory(plot_3d)
 add_subdirectory(plotting)
 add_subdirectory(resource_spawner)
-add_subdirectory(select_entities)
 add_subdirectory(scene_manager)
+add_subdirectory(select_entities)
 add_subdirectory(shapes)
 add_subdirectory(spawn)
 add_subdirectory(transform_control)
 add_subdirectory(video_recorder)
 add_subdirectory(view_angle)
 add_subdirectory(visualization_capabilities)
 add_subdirectory(visualize_contacts)
-add_subdirectory(visualize_lidar)
 add_subdirectory(visualize_frustum)
+add_subdirectory(visualize_lidar)

src/systems/CMakeLists.txt

@@ -104,6 +104,7 @@ add_subdirectory(environment_preload)
 add_subdirectory(environmental_sensor_system)
 add_subdirectory(follow_actor)
 add_subdirectory(force_torque)
+add_subdirectory(free_space_explorer)
 add_subdirectory(hydrodynamics)
 add_subdirectory(imu)
 add_subdirectory(joint_controller)

src/systems/free_space_explorer/CMakeLists.txt

@@ -0,0 +1,8 @@
+gz_add_system(free-space-explorer
+  SOURCES
+  FreeSpaceExplorer.cc
+  PUBLIC_LINK_LIBS
+    gz-common::gz-common
+    gz-math::gz-math
+    gz-plugin::core
+)