dcronqvist / DotGL

👾 a low level OpenGL 4.6 binding for C#

👾 DotGL

A low level OpenGL 4.6 binding for C#. Contains exact function signatures (unsafe with pointers) and safe wrappers for all OpenGL functions. Allows for configuring which functions to expose (unsafe/safe or both) and which OpenGL version to target.

How to use

1. Download the GL.cs file and add it to your project somewhere.
2. Include the following in your .csproj file.
   • Configure OpenGLVersionMajor and OpenGLVersionMinor to your desired OpenGL version.
   • Configure OpenGLProfile to either CORE or COMPAT. (COMPAT not implemented yet)
   • Configure OpenGLWrapperAPI to either SAFE, UNSAFE or BOTH.

<Project ...>
    ...
    <PropertyGroup>
        <!-- GL.cs configuration options! -->

        <!-- Profile: CORE/COMPAT -->
        <!-- COMPAT not implemented yet -->
        <OpenGLProfile>CORE</OpenGLProfile>

        <!-- Version: Any valid OpenGL version from 1.0-4.6 -->
        <OpenGLVersionMajor>3</OpenGLVersionMajor>
        <OpenGLVersionMinor>3</OpenGLVersionMinor>

        <!-- Defining exposed wrapper API (SAFE/UNSAFE/BOTH) -->
        <!-- SAFE: Only safe functions are exposed -->
        <!-- UNSAFE: Only unsafe functions are exposed -->
        <!-- BOTH: Both safe and unsafe functions are exposed -->
        <OpenGLWrapperAPI>BOTH</OpenGLWrapperAPI>

        <!-- Defining constants for compile time availability of APIs -->
        <DefineConstants>$(DefineConstants);OGL_V_$(OpenGLVersionMajor)_$(OpenGLVersionMinor);OGL_P_$(OpenGLProfile);OGL_WRAPPER_API_$(OpenGLWrapperAPI)</DefineConstants>
    </PropertyGroup>
    ...
</Project>

3. Done!

Example with DotGLFW

The following example shows how to use this binding with DotGLFW. The example is not complete, but should give a good idea of how this binding is supposed to be set up and used.

// Gives access to all OpenGL functions without the `GL.` prefix
using static DotGL.GL; 

// Retrieve OpenGL version and profile from `.csproj` file
// Does some switching depending on which constants are defined
int glMajor = GL.GetProjectOpenGLVersionMajor();
int glMinor = GL.GetProjectOpenGLVersionMinor();
string glProfile = GL.GetProjectOpenGLProfile();

// Normal GLFW window creation
Glfw.Init();
Glfw.WindowHint(Hint.ClientAPI, ClientAPI.OpenGLAPI);
Glfw.WindowHint(Hint.ContextVersionMajor, glMajor);
Glfw.WindowHint(Hint.ContextVersionMinor, glMinor);
OpenGLProfile profile = glProfile switch
{
    "CORE" => OpenGLProfile.CoreProfile,
    "COMPAT" => OpenGLProfile.CompatProfile,
    _ => throw new Exception("Invalid OpenGL profile!")
}
Glfw.WindowHint(Hint.OpenGLProfile, profile);
Window window = Glfw.CreateWindow(800, 600, "DotGL", Monitor.NULL, Window.NULL);

// Set the current context to the newly created window
Glfw.MakeContextCurrent(window);

// Load all OpenGL functions for the given version and profile
GL.Import(Glfw.GetProcAddress);

// OpenGL functions now working!
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);