updated: ROS2 mixin docs

Author: afxalz

docs/10-prerequisities/25-ros2/50-ros1-ros2-patterns/workspace_profiles.md

@@ -1,25 +1,17 @@
 ---
-title: workspace profiles
-pagination_label: ROS2 workspace profiles
+title: Mixin AKA Workspace Profiles
+pagination_label: ROS2 workspace profiles mixin
 description: ROS2 workspace profiles
 ---
 
 # ROS2 workspace profiles
 
 ## Setting work-space wide configurations
 
-Create a file `colcon_defaults.yaml` in the workspace's root.
-Build parameters can be set, e.g., for limiting the number of build threads:
-
-```yaml
-build:
-  parallel-workers: 8
-```
-
 ## Mixin
+A `mixin` is a tag given to a set of parameters that you may want to pass to `colcon` during build (maybe used with other `colcon` commands).
 
-**"Manually adding arguments but with extra steps"**
-
+### Adding Mixins to `colcon`
 Add the official mixin repository:
 ```bash
 colcon mixin add default https://raw.githubusercontent.com/colcon/colcon-mixin-repository/master/index.yaml
@@ -40,11 +32,48 @@ Build with particular mixin:
 colcon build --mixin rel-with-deb-info
 ```
 
-Use mixins automatically: Use the `colcon_defaults.yaml` file:
+### Adding a custom Mixins
+- Make a `build_types.mixin` file that defines custom mixins(`JSON` format)
+```json
+{
+    "build": {
+        "debug": {
+            "cmake-args": ["-DCMAKE_BUILD_TYPE=Debug",
+                            "-DCMAKE_EXPORT_COMPILE_COMMANDS=ON",
+                            "-DCMAKE_CXX_FLAGS='-std=c++17 -Og'",
+                            "-DCMAKE_C_FLAGS='-Og'"]
+        },
+        "rel-with-deb-info": {
+            "cmake-args": ["-DCMAKE_BUILD_TYPE=RelWithDebInfo",
+                            "-DCMAKE_EXPORT_COMPILE_COMMANDS=ON",
+                            "-DCMAKE_CXX_FLAGS='-std=c++17'"]
+        },
+        "release": {
+            "cmake-args": ["-DCMAKE_BUILD_TYPE=Release",
+                            "-DCMAKE_EXPORT_COMPILE_COMMANDS=ON",
+                            "-DCMAKE_CXX_FLAGS='-std=c++17'"]
+        }
+    }
+}
+```
+- Make an `index.yaml` file for `colcon mixin` to find all the defined mixins
+```bash
+mixin:
+  - build_types.mixin
+```
+- Add the file to the mixin repository and update the mixins:
+```bash
+colcon mixin add mrs file://<path-to-directory-with-mixin-index-file>/index.yaml
+colcon mixin update mrs
+```
+Add these lines to your `.zshrc` or `.bashrc` to automatically access the mixins with each new shell.
 
+## Using Mixins for build
+- `colcon` uses configuration files for building, testing and installing packages. It's good practice to have a `colcon_defaults.yaml` in the root of your ROS2 workspace.
+- The file can have different parameters as described at https://colcon.readthedocs.io/en/released/reference/verb/build.html. For eg. using a particular mixin and limiting the threads during build would look like
 ```yaml
 build:
+  parallel-workers: 8
   mixin:
     - rel-with-deb-info
-    - compile-commands
-```
+```

docs/10-prerequisities/25-ros2/index.md

@@ -1,5 +1,5 @@
 ---
-title: ROS
+title: ROS2
 pagination_label: Robot Operating System
 description: Robot Operating System
 ---