OPEN SOURCE GAME ENGINE
An open source game engine with ECS, physics, audio, and C# scripting. Built in C and C++ with OpenGL. Use it as a framework or a full engine.
Kolpa is a game engine written in C and C++. It has a C99 framework layer for rendering, input, audio, and math, and a C++20 engine layer with ECS, scene management, physics, and optional C# scripting.
The kolpa C library gives you window, input, rendering, audio, and math. No ECS, no scenes, no scripting. Just a fast, readable C API for making games.
The C++ engine layer adds GameObjects, Components, Behaviours, Systems, physics, audio DSP, resource pipelines, and C# scripting via .NET 10 with hot reload.
$ git clone https://github.com/gabriel-aplok/kolpa-lib.git
$ cd kolpa-lib
$ dotnet build build/Kine.Build
$ build/Kine.Build.exe buildExplore the sub-systems, pipelines, and frameworks built into Kolpa Engine.
Write gameplay logic in C# with full type safety. Direct access to .NET runtime, multithreading, and high-level libraries via hot-reloaded assemblies.
public class BasePlayer : EntityComponent
{
public float Speed { get; set; } = 5.0f;
public override void OnUpdate(float deltaTime)
{
Vector3 input = GameInput.GetMovementVector();
Transform.Translate(input * Speed * deltaTime);
}
}Forward rendering pipeline with MSAA anti-aliasing. Supports dynamic lights, shadow mapping, light probes, and depth pre-passes for efficient scene rendering.
Save code changes and see updates immediately in the running viewport. The editor reloads assemblies without resetting runtime state or dropping frames.
Action-based input system for controllers, keyboard, and mouse. Unified input state shared between editor and standalone packages.
// Action-based input routing.
if (Input!.IsActionPressed("Jump"))
Velocity.Y = JumpForce;
var moveDir = Input.GetAxis2D("MoveX", "MoveY");PBR material system with node-based controls or code parameters. Configure reflectivity, roughness, normal maps, and emissive properties.
Write GLSL code directly for materials and fullscreen post-process passes. The editor compiles shaders immediately upon saving.
// Write native GLSL directly in engine.
vec4 EvaluateUnlit(MaterialInput input)
{
float rim = pow(1.0 - clamp(dot(
normalize(input.Normal), input.ViewDir), 0.0, 1.0), 3.0);
return vec4(input.BaseColor + rim * vec3(0.2, 1.0, 0.4), 1.0);
}Pluggable physics backend supporting multiple implementations. Switch between Jolt, Box3D, or a lightweight dummy backend per project needs.
Visual state machines and blend trees for character animation. GPU-accelerated skeletal skinning with real-time playback in the editor.
Hardware-accelerated immediate mode UI framework. Build HUDs, editor panels, and overlays with a simple draw-call API.
// Immediate mode UI drawing.
_UI.Draw(() =>
{
using (UI.Panel("Inventory"))
{
UI.Header("Items");
if (UI.Button("Equip Sword"))
Player.Equip(ItemId);
}
});Edit C# and GLSL code inside the engine viewport. Syntax highlighting, auto-completions, and script diagnostics without leaving the editor.
Level prototyping with CSG operations. Add, subtract, and intersect shapes to generate static meshes for rapid level design.
One-click build pipeline. Compile code, cook assets, strip unused data, and write archives into a standalone executable.
Import 3D models, textures, and animations. The pipeline converts assets into optimized binary formats for fast loading and low memory usage.
$ kine build --assets import
$ Converting model.fbx to .kmd...
$ Converting texture.png to .ktx...
$ Asset pipeline complete (2.4s)Discover featured games and technical prototypes created by the team and the community.
News, tutorials, and development notes from the Kolpa Engine team.
How Kolpa renders 3D scenes with OpenGL and the roadmap for future renderer improvements.
A quick walkthrough of a gameplay component, from blank file to running in the engine.
Why this blog exists, what we are building, and how to follow along.