sdl3_node2d_lua

License: MIT

Status:

• work in progress.

Project Overview

sdl3_node2d_lua is a sample project demonstrating a 2D node-based editor using SDL3, SDL_ttf, and FreeType. It renders a graphical interface with the "Kenney Mini" font and supports interactive node manipulation. Built for Windows using the MSYS2/MinGW-w64 environment, it serves as a foundation for developing node-based graphical applications, such as visual scripting or dataflow editors. The project uses SDL3’s software rendering for simplicity and portability.

sdl3_node2d_lua/
├── include
│   ├── module_gl.h.c
│   └── module_lua.h.c
├── src/
│   ├── main.c
│   ├── module_gl.h.c
│   └── module_lua.h.c
├── build/ - build files
├── docs/ - work in progress
├── glad/ - library for opengl
├── build.bat
├── CMakeLists.txt
├── Kenney Mini.ttf
├── README.md
├── run.bat
├── script.lua

Features

• Node2D Editor:

  • Dragging: Drag nodes by left-clicking and moving the mouse.
  • Input/Output Ports: Green squares for input ports, red squares for output ports, with text labels (e.g., “In1”, “Out1”).
  • Connections:
    • Left-click a red output square, then a green input square to connect with a white line.
    • Middle-click a disconnect a specific connection.
  • Node Addition: Right-click away from green squares to add a new node at the click position.
  • delete. drag and delete key.
  • Panning: Middle-click hold and drag to pan the view.
  • Zooming: Scroll wheel to zoom in/out (0.5x to 2.0x), centered on the mouse cursor.
  • Grid g key to toggle snap
  • Menus: Planned for node type selection and configuration.
  • Variables: Planned for node data storage.
  • Functions: Planned for node-based logic or scripting.

• Rendering:

  • Nodes rendered as blue 100x100 squares, scaling with zoom.
  • Red debug rectangle outlines nodes during dragging.
  • Yellow lines indicate active connections during creation.

• Static Linking: SDL3, SDL_ttf, and FreeType are statically linked to avoid DLL dependencies.

• Cross-Platform Build: Configured with CMake for MinGW-w64, adaptable to other platforms.

  Does not have variables and functions. Just a simple node 2D with the connectors.

Goals

• Provide a minimal, working example of SDL3 and SDL_ttf for interactive 2D graphics.
• Serve as a extensible base for a node-based editor (e.g., visual scripting, shader graphs).
• Ensure an easy setup for Windows developers using MSYS2, with clear build instructions.
• Expand functionality with menus, variables, and functions for a fully-featured editor.

Requirements

Software

• Operating System: Windows 10 or later (64-bit).
• MSYS2: Software distribution and build platform for Windows.
  • Download: MSYS2 Installer
• CMake: Version 3.10 or later (install via MSYS2).
• MinGW-w64 Toolchain: Provides GCC, G++, and build tools (install via MSYS2).
• Git: Optional, for cloning the repository.
• Font File: “Kenney Mini.ttf” (included in the project directory).

Dependencies

The following libraries are fetched and built via CMake’s FetchContent:

• Lua: Version 5.4.7 ( lua script )
• SDL3: Version 3.2.14 (window and graphics handling).
• SDL_ttf: Version 3.2.2 (font rendering for SDL3).
• FreeType: Version 2.13.3 (font engine for SDL_ttf).
• Font: “Kenney Mini.ttf” (must be in the project root). https://kenney.nl/assets/kenney-fonts
• Glad: Version 2.0.8 ( opengl ) https://gen.glad.sh https://github.com/Dav1dde/glad

# Added glad default
# https://gen.glad.sh/
    # - Generator: c
    # - API: gl=3.3
    # - Profile: Core
    # - Options
    #     - Generate a loader: Checked

MSYS2 Packages

Setup Instructions

1. Install MSYS2:

   • Download and install MSYS2 from msys2.org.
   • Open the MSYS2 MinGW 64-bit terminal (C:\msys64\mingw64.exe).

2. Install Dependencies:

   bash

   pacman -Syu

   update system.

   bash

   pacman -S mingw-w64-x86_64-gcc mingw-w64-x86_64-g++ mingw-w64-x86_64-cmake mingw-w64-x86_64-make mingw-w64-x86_64-pkgconf
   

   Install packages for dev tool.

3. Clone or Download the Project:

   • Clone with Git (if available):

     bash

     git clone https://github.com/Lightnet/sdl3_node2d_lua.git
     cd sdl3_node2d_lua

   • Or download and extract the project ZIP, then navigate to the directory in the MSYS2 terminal.

4. Ensure Font File:

   • Verify that Kenney Mini.ttf is in the project root directory (sdl3_node2d_lua/Kenney Mini.ttf).

5. Build the Project:

   • Create a build directory and run CMake:

     bash

     mkdir build
     cd build
     cmake .. -G "MinGW Makefiles" -DCMAKE_BUILD_TYPE=Debug
     cmake --build . --config Debug

   • Alternatively, use the provided run.bat (ensure MSYS2’s mingw64/bin is in your PATH):

     cmd

     @echo off
     setlocal
     set MSYS2_PATH=C:\msys64\mingw64\bin
     set PATH=%MSYS2_PATH%;%PATH%
     if not exist build mkdir build
     cd build
     cmake .. -G "MinGW Makefiles" -DCMAKE_BUILD_TYPE=Debug -DCMAKE_C_COMPILER=%MSYS2_PATH%\gcc.exe -DCMAKE_CXX_COMPILER=%MSYS2_PATH%\g++.exe
     cmake --build . --config Debug
     endlocal
     

   • This generates the executable in build/src/sdl3_node2d_editor.exe.

6. Run the Application:

   • From the build directory:

     bash

     build/sdl3_node2d_editor.exe

   • Or double-click run.bat if it’s configured to run the executable.

Usage

• Dragging: Left-click and drag a node to move it.
• Connections:
  • Left-click a red output square, then a green input square to create a white connection line.
  • Right-click a green input square to disconnect its connection.
• Node Addition: Right-click away from green squares to add a new node.
• Panning: Middle-click and drag to pan the view.
• Zooming: Scroll wheel to zoom in/out (0.5x to 2.0x).
• Debugging: Console logs show drag positions, connections, disconnections, node additions, and zoom levels.

Troubleshooting

• Font Not Found:

  • Ensure Kenney Mini.ttf is in the project root. If missing, download from Kenney Fonts.

• Build Errors:

  • Verify MSYS2 packages are installed.
  • Check CMake output for missing dependencies.
  • Ensure run.bat points to the correct MSYS2 path (C:\msys64\mingw64\bin).

• Rendering Issues:

  • If nodes or lines don’t scale/pan, verify the SDL3 version (3.2.14).

  • Test with software rendering:

    c

    SDL_SetHint(SDL_HINT_RENDER_DRIVER, "software");

    (Add before SDL_CreateWindowAndRenderer in main.c.)

• Performance:

  • Reduce MAX_NODES or MAX_CONNECTIONS in main.c if rendering lags.

Future Roadmap

• Menus: Implement a right-click menu UI for selecting node types and properties.
• Variables: Add support for nodes to store and manipulate data (e.g., integers, floats).
• Functions: Enable nodes to define and execute logic (e.g., math operations, conditionals).
• Node Types: Support different node categories (e.g., math, logic, input/output).
• Save/Load: Allow saving and loading node graphs to/from files.
• OpenGL Integration: Optionally switch to OpenGL for enhanced rendering (if needed).

Credits:

• Blender Node 2D editor idea.
• https://kenney.nl/assets/kenney-fonts
• Grok
  • work code
  • manual feed data and mistakes.
• https://github.com/Dav1dde/glad
  • examples