TrussSketch

AngelScript-based scripting engine for TrussC Web Playground.

Overview

TrussSketch powers tcScript, a browser-based creative coding playground. Write C++-like script code and see it run instantly in WebAssembly.

float hue = 0.0f;

void setup() {
    logNotice("Hello from TrussSketch!");
}

void update() {
    hue += 0.005f;
    if (hue > 1.0f) hue = 0.0f;
}

void draw() {
    clear(1.0f);

    for (int i = 0; i < 8; i++) {
        float angle = TAU * float(i) / 8.0f + getElapsedTimef();
        float x = getWindowWidth() / 2.0f + cos(angle) * 120.0f;
        float y = getWindowHeight() / 2.0f + sin(angle) * 120.0f;

        setColorHSB(fmod(hue + float(i) * 0.125f, 1.0f), 0.7f, 0.9f);
        drawCircle(x, y, 25.0f);
    }
}

void mousePressed(float x, float y, int button) {
    logNotice("Click at " + x + ", " + y);
}

Features

• Instant feedback: Edit code and click Run to see changes immediately
• Zero server load: Everything runs client-side in WebAssembly
• Chromebook friendly: Works on low-spec devices
• Share your creations: Generate URLs to share your sketches

Building

Requirements

• CMake 3.20+
• Emscripten SDK (for Web builds)
• TrussC library

Build for Web (WASM)

./build-web.command

Or manually:

mkdir build-web && cd build-web
emcmake cmake ..
cmake --build .

Output files land in bin/:

• TrussSketch.js
• TrussSketch.wasm

Deploy to R2

After building, deploy both files to Cloudflare R2:

cd bin
wrangler r2 object put trussc-wasm/sketch/TrussSketch.wasm --file TrussSketch.wasm --remote
wrangler r2 object put trussc-wasm/sketch/TrussSketch.js --file TrussSketch.js --remote

Build for macOS (Development)

mkdir build-macos && cd build-macos
cmake ..
cmake --build .

API Reference

See the online reference: trussc.org/tcscript/reference/

The full TrussC C++ API reference lives at trussc.org/reference/.

Architecture

TrussSketch/
├── src/
│   ├── main.cpp           # Entry point, Emscripten exports
│   ├── tcApp.cpp/h        # TrussC app with script lifecycle
│   └── tcScriptHost.cpp/h # AngelScript wrapper with TrussC bindings
├── testScript/            # Sample .tcs scripts used for local testing
├── CMakeLists.txt
├── ROADMAP.md             # Planned features
└── README.md

AngelScript itself is pulled in via CMake FetchContent (see CMakeLists.txt), so there is no vendored script engine in the source tree.

API Documentation Generation

The API reference is generated from TrussC/docs/api-definition.yaml:

cd ../docs/scripts
node generate-docs.js

This generates tcscript-api.js for the web playground's autocomplete and reference page, and fills the auto-generated C++ API index in TrussC/docs/FOR_AI_ASSISTANT.md.

License

MIT License - see TrussC for details.

Links

• tcScript Playground
• tcScript API Reference
• TrussC Framework
• AngelScript