Update CI workflow with dependency installation per job

.github/workflows/c-cpp.yml

@@ -7,47 +7,82 @@ on:
     branches: [ "main" ]
 
 jobs:
-  installing-dependencies:
+  install-dependencies:
+    name: Installing Dependencies
     runs-on: ubuntu-latest
+    container: ghcr.io/gravity-sim/deps:latest
     steps:
       - uses: actions/checkout@v4
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y build-essential libgl1-mesa-dev libglew-dev libglfw3-dev libopenmpi-dev
+      - name: Cache build artifacts
+        uses: actions/cache@v3
+        with:
+          path: |
+            src/*.o
+            tests/*.o
+          key: ${{ runner.os }}-build-${{ hashFiles('**/*.c') }}
+          restore-keys: ${{ runner.os }}-build-
+      - name: Setup complete
+        run: echo "Dependencies are pre-installed in the container"
 
   build:
+    name: Build
     runs-on: ubuntu-latest
-    needs: installing-dependencies
+    needs: install-dependencies
+    container: ghcr.io/gravity-sim/deps:latest
     steps:
       - uses: actions/checkout@v4
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y build-essential libgl1-mesa-dev libglew-dev libglfw3-dev libopenmpi-dev
+      - name: Restore build cache
+        uses: actions/cache@v3
+        with:
+          path: |
+            src/*.o
+            tests/*.o
+          key: ${{ runner.os }}-build-${{ hashFiles('**/*.c') }}
+          restore-keys: ${{ runner.os }}-build-
       - name: Build
         run: make
 
   test:
+    name: Test
     runs-on: ubuntu-latest
     needs: build
+    container: ghcr.io/gravity-sim/deps:latest
     steps:
       - uses: actions/checkout@v4
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y build-essential libgl1-mesa-dev libglew-dev libglfw3-dev libopenmpi-dev
+      - name: Restore build cache
+        uses: actions/cache@v3
+        with:
+          path: |
+            src/*.o
+            tests/*.o
+          key: ${{ runner.os }}-build-${{ hashFiles('**/*.c') }}
+          restore-keys: ${{ runner.os }}-build-
       - name: Test
         run: make test
 
   make:
+    name: Make
     runs-on: ubuntu-latest
     needs: test
+    container: ghcr.io/gravity-sim/deps:latest
     steps:
+    - uses: actions/checkout@v4
+    - name: Install dependencies
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y build-essential libgl1-mesa-dev libglew-dev libglfw3-dev libopenmpi-dev
+    - name: Build
+      run: make
+    - name: Test
+      run: make test
       - uses: actions/checkout@v4
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y build-essential libgl1-mesa-dev libglew-dev libglfw3-dev libopenmpi-dev
+      - name: Restore build cache
+        uses: actions/cache@v3
+        with:
+          path: |
+            src/*.o
+            tests/*.o
+          key: ${{ runner.os }}-build-${{ hashFiles('**/*.c') }}
+          restore-keys: ${{ runner.os }}-build-
       - name: Make
-        run: make
+        run: make

README.md

@@ -10,6 +10,7 @@ This project is a continuation of fluid simulation concepts, extended to simulat
 - [Installation](#installation)
 - [Build](#build)
 - [Usage](#usage)
+- [Continuous Integration](#continuous-integration)
 - [Project Layout](#project-layout)
 - [Acknowledgments](#acknowledgments)
 - [License](#license)
@@ -74,6 +75,14 @@ To set up and compile the project on your local machine, follow these steps:
    ./gravity_simulation
    ```
 
+## Continuous Integration
+
+This project uses a GitHub Actions workflow that runs inside a prebuilt Docker
+container containing all required OpenGL dependencies. The workflow consists of
+four sequential jobs: **Installing Dependencies**, **Build**, **Test**, and
+**Make**. Compiled object files are cached between jobs to speed up subsequent
+steps.
+
 ## Usage
 
 To run the simulation: