LeveGL

A simple rendering library for a simpler world. 🍃

Documentation

Introduction

LeveGL aims to empower you to build and prototype games quickly. It is a lightweight rendering library written in C99, drawing inspiration from the simplicity of Raylib and the robustness of liblava. Originally a study project, the focus is on keeping the code clear, simple, and easy to work with.

It started as a learning project, but I’ve come to appreciate its simple and practical design, which makes it great for experimenting.

Screenshots

 

 

Usage

Caution

LeveGL is currently in a highly work-in-progress state. The API is unstable and subject to significant changes. It is intended for learning and experimentation purposes.

To get started with, here's a simple example that demonstrates the basics:

This minimal code creates a window and draws a static triangle in the center. The triangle is drawn using simple trigonometric calculations to position its vertices equidistant from the center point.

#include "levegl/levegl.h"

int main( void )
{
    // Set up window
    const int width = 480;
    const int height = 272;

    InitWindow( width, height, "LeveGL Triangle" );
    SetTargetFPS( 60 );

    // Calculate fixed triangle points
    float cx = width / 2.0F;
    float cy = height / 2.0F;
    float r = 100.0F;

    // Points for an upward-facing triangle
    float x1 = cx;                        // Top point
    float y1 = cy - r;
    float x2 = cx - r * 0.866F;           // Bottom left (cos(120°))
    float y2 = cy + r * 0.5F;             // Bottom left (sin(120°))
    float x3 = cx + r * 0.866F;           // Bottom right (cos(240°))
    float y3 = cy + r * 0.5F;             // Bottom right (sin(240°))

    // Main loop
    while( !ShouldQuit() )
    {
	// Draw triangle
	BeginDrawing();
        {
		ClearBackground( WHITE );
		DrawTriangle( (int)x1, (int)y1, (int)x2, (int)y2, (int)x3, (int)y3, BLACK );
	}
        EndDrawing();
    }

    // Close window and clean up resources before exiting
    CloseWindow();

    return 0;
}

Build & Run

CPM.cmake

1. First, set up CPM.cmake in your project:

   mkdir -p cmake
   wget -O cmake/CPM.cmake https://github.com/cpm-cmake/CPM.cmake/releases/latest/download/get_cpm.cmake

2. In your CMakeLists.txt, add the following lines after project(...):

   include(cmake/CPM.cmake)
   
   CPMAddPackage("gh:SOHNE/LeveGL@0.0.1")
   
   add_executable(your_target main.cpp)
   target_link_libraries(your_target PRIVATE LeveGL::LeveGL)
   

Roadmap

• Design and implement an OpenGL Abstraction Layer
• Font rendering system
• 3D shapes and models
• Dedicated documentation page

Contributing

The majority of LeveGL code is open-source. We are committed to a transparent development process and highly appreciate any contributions. Whether you are helping us fix bugs, proposing new features, improving our documentation or spreading the word - we would love to have you as a part of the SOHNE/LeveGL community. Please refer to our contribution guidelines.

• Bug Report: If you see an error message or encounter an issue while using LeveGL, please create a bug report.

• Feature Request: If you have an idea or if there is a capability that is missing and would make development easier and more robust, please submit a feature request.

• Documentation Request: If you're reading the LeveGL docs and feel like you're missing something, please submit a documentation request.

License

LeveGL is licensed under the zlib/libpng license.

You are free to use, modify, and distribute this library under the following conditions:

1. No Misrepresentation: You must not misrepresent the origin of the software. If you use this software in a product, an acknowledgment in the product documentation is appreciated but not required.
2. Modified Versions: Altered source versions must be clearly marked as such and must not be misrepresented as the original software.
3. License Notice: This license notice may not be removed or altered from any source distribution.

For the full license text, please see the LICENSE file.

LeveGL depends on several third-party libraries and dependencies, each distributed under its own license. It is the responsibility of the user to review and comply with these additional licenses.

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