Cmake Vs Make
CMake + Make Build Flow for OpenGL Projects (Triangle Example)
This post summarizes the build system flow using CMake and Make for a simple OpenGL triangle rendering project, using GLFW, GLAD, and C++.
Folder Structure
Your project layout might look like this:
triangle_glfw/
├── include/ # GLAD headers
│ └── glad/
├── src/ # C++ source files
│ ├── main.cpp
│ └── glad.c
├── CMakeLists.txt # Build instructions
├── build/ # CMake-generated build folder (after configuration)
What is CMake?
CMake is a cross-platform build system generator. It reads CMakeLists.txt to understand how to build your code, and generates a platform-specific build system (e.g., Makefiles on macOS/Linux).
What is Make?
Make is a build tool that uses the generated Makefile to:
- Compile your
.cppfiles - Link them into an executable
- Track which files have changed and only rebuild what’s needed
Build Workflow
You’ll typically follow this 3-step process:
1. Generate the Build System (using CMake)
mkdir build
cd build
cmake ..
This runs CMake and generates the Makefile based on your CMakeLists.txt.
The .. means: “Look for CMakeLists.txt in the parent folder.”
2. Build the Project (using Make)
make
This compiles your project using the rules from the generated Makefile.
It will produce an executable, typically named based on add_executable(...) in your CMakeLists.txt.
Example:
add_executable(Triangle src/main.cpp src/glad.c)
→ Output will be Triangle
3. Run the Program
From inside the build/ folder:
./Triangle
You should see your first triangle rendered in a GLFW window.
When to Rerun CMake?
| You changed… | Run make again? |
Run cmake .. again? |
|---|---|---|
Edited .cpp file |
Yes | No |
| Added new source/header | Yes | Yes (recommended) |
Edited CMakeLists.txt |
Yes | Yes |
| Changed library setup | Yes | Yes |
Optional: Clean Rebuild
If things get weird or stale:
rm -rf build/
mkdir build
cd build
cmake ..
make
This resets the entire build state.
Summary
| Tool | Role |
|---|---|
CMake |
Generates build system from CMakeLists.txt |
Make |
Compiles source files into an executable |
./Triangle |
Runs the program after successful build |
This setup works great for small OpenGL projects and scales easily with more complexity later (e.g., shader loading, asset pipelines, camera systems).
Happy coding!