What is the difference between setting worldposition and position?

🌵 Needle Engine
1

Are WorldPosition and Position the same ? If not, where do they differ ?

2

Great question, Enthusiast!

Step-by-step plan in pseudocode:

  1. Explain the concept of position and worldPosition in the Needle Engine/Three.js context.
  2. Describe scenarios where position and worldPosition give different results.
  3. Give a concise answer about whether they are the same.
  4. Share a minimal technical example.

Explanation:

  • position is the local position of an object relative to its parent in the scene graph.
  • worldPosition is the global position of the object in the world coordinate space, factoring in all parent transforms (position, rotation, scale).

They are NOT the same:

  • If the object has no parent, then position and worldPosition are equal.
  • If the object is parented, position is relative to its parent, but worldPosition represents its absolute coordinates in the scene.

Example:

import { Behaviour, GameObject } from "@needle-tools/engine";

export class PositionDemo extends Behaviour {
    start() {
        // Get this object's local position
        const localPos = this.gameObject.position;
        // Get world position
        const worldPos = GameObject.getWorldPosition(this.gameObject);

        console.log("Local Position:", localPos);
        console.log("World Position:", worldPos);
    }
}
  • If you move a parent, the child’s worldPosition changes but its position remains the same relative to the parent.

Tip for better questions:

  • Specify if you refer to a particular API or context (e.g., Unity, Three.js, Needle Engine).
  • Ask about code examples to clarify differences.

More on the API: Three.js Object3D.position
Needle Engine Docs

Would you like an example with parent-child objects to clarify?

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3

Hi, the bot reply is correct generally. position is localspace in three.js so we added worldPosition to make it easier to work with worlspace coordinates if necessary

this.gameObject.worldPosition