# View Rigidbody 2D Wire Frame

Simple question. When I prototype game ideas I like to create objects without having to attach sprites. Is it possible to create a Rigidbody 2D in unity, set its size and render its wire frame? I am using a unity in 2D mode.

Thanks!

• The wire frame of what? Do you want to see the collider? Sep 29 '14 at 2:50
• The Rigidbody isn't viewable… It's the collider attached. Sep 29 '14 at 4:04

To answer your question directly, it is possible to set the scene/game windows to enable gismos for your colliders but they will only be displayed when that gameobject (or a parent) is selected in the hierarchy.

This can be improved by attaching a script that implements OnDrawGizmos(), as an example here is an implementation that would visualize a BoxCollider2D:

using UnityEngine;

public class DisplayBoxCollider : MonoBehaviour {
public Color LineColor = Color.green;
private BoxCollider2D _boxCollider;
private Transform _transform;

public void Start () {
_transform = GetComponent<Transform>();
_boxCollider = GetComponent<BoxCollider2D>();
}

public void OnDrawGizmos() {
if (_boxCollider) {
DrawBox(_transform.position, _boxCollider.size, LineColor);
}
}

private void DrawBox(Vector3 origin, Vector3 size, Color color) {
Vector2 halfSize = size/2;

float top = origin.y + halfSize.y;
float bottom = origin.y - halfSize.y;
float left = origin.x - halfSize.x;
float right = origin.x + halfSize.x;

Gizmos.color = color;
Gizmos.DrawLine(new Vector3(left, top), new Vector3(right, top));
Gizmos.DrawLine(new Vector3(right, top), new Vector3(right, bottom));
Gizmos.DrawLine(new Vector3(right, bottom), new Vector3(left, bottom));
Gizmos.DrawLine(new Vector3(left, bottom), new Vector3(left, top));
}
}


However this approach leads to a fair bit of work if you require support for all of the collider types.

Instead I take the following approach:

• Use an image editor to create a set of small white png files. (e.g. 8x8, 8x16, 16x8 to cover a few basic senarios)
• Import these images into the unity project (Texture Type: Sprite, Sprite Mode: Single, Pixels to Units: 8)
• Attach a sprite to a GameObject, then customize the SpriteRenderer's Color to disambiguate between different types.

Using these placeholder sprites results in a minimalist representation of each object and the space it occupies, suitable for basic prototyping. By having a couple of sizes I can have sprites 1x1, 1x2, 2x1 units in size without having modify to the scale.