What on Earth?

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What on Earth? ​

What on Earth? is a tool for exploring quaternions, geometry, and satellite perspectives—all from the comfort of your browser. It provides an interactive 3D environemtn to perform complex geometric calculations, visualize scenes from a satellite’s viewpoint, and optimize quaternions under various constraints.

Key Features ​

  • Geometric Calculations: Compute angles, distances, and other geometrical properties.
  • Satellite Perspectives: Simulate and analyze views from a satellite’s camera, complete with orientation and field of view adjustments.
  • Quaternion Optimization: Determine the best quaternion given constraints such as:
    • Specific camera orientations.
    • Alignment of secondary vectors or targets.
  • User-Driven Scripting: Write and execute scripts directly in the app’s built-in editor using a custom API or DSL, enabling:
    • Adding new points or objects to the scene.
    • Performing calculations on-the-fly.
    • Automating workflows for repeated tasks.
    • Time-based simulations with adjustable simulation time
    • ... much more coming soon.

Getting Started ​

User Interface ​

User Interface

The application interface is divided into the following areas:

  1. Simulation View (Left): The main 3D visualization area showing the Earth globe, satellite points, and other geometric elements. You can rotate and zoom the view using your mouse.

  2. Code Editor (Right): A full-featured code editor where you can write and edit your script using the application's DSL. The editor includes syntax highlighting and auto-completion features.

  3. Execute Button: Located below the editor, this button runs your current script and update the simulation accordingly.

  4. Settings Tabs: On the left edge of the editor panel, vertical tabs provide access to additional features:

  • Editor: The main coding interface
  • Settings: Configuration options for the simulation, including time controls and visualization settings

Example workflow ​

Let's walk through a practical example of using What on Earth? to debug quaternion orientations. This workflow will show you how to:

  • Position a satellite
  • Create reference points
  • Analyze orientations
  • Calculate angles between vectors

Here's a complete example you can copy/paste into the integrated editor:

javascript
// Move the default point, `sat`, near Helsinki
mov("sat", [62.0, 34.0, 500.0], true);

// Kuva Space HQ
let ksCoords = geo2xyz([60.186, 24.828, 0]);
addPoint("KS", ksCoords);

// Create a line between satellite and point
createLine("sat2KS", "sat", "KS");

// Apply a test quaternion rotation
rot("sat", [-0.6313439, -0.1346824, -0.6313439, -0.4297329]);

// Calculate angle between satellite's z-axis and the line
angle("sat2KS", point("sat").frame.z);

Full details on how this example works can be found the debugging quaternions workflow example. For more examples and detailed workflows, check out our workflow guides.

DSL Documentation ​

Dive into the scripting capabilities provided by the app’s DSL. Read the documentation.