Gizmo Sensors

This code is for Unity engine.

Those sensors use Unity Physics API and they provide Gizmos which work inside Editor - so you can preview what sensors are doing.

Useful for anyone to see in 'real-time' how Raycasting works in Unity.

Types of sensors

• LineCast (Physics.Linecast)
• BoxCast (Physics.BoxCast)
• SphereCast (Physics.SphereCast)
• CheckBox (Physics.CheckBox)
• CurvedCast (Physics.Linecast - multiple calls)
• FullBoxCast (Physics.BoxCastAll)

How do I use this?

• Single script (Sensor.cs),

In inspector

• Add Sensor.cs to GameObject,
• Set "Hit Mask" (LayerMask),
• Select sensor type in "Raycast Type",
• Change other settings to change shape of your Sensor,

In code

• Get reference to Sensor by calling "var s = GetComponent()" or making Sensor s public variable and setting reference to it
• Call "s.Scan()" from code whenever you wish to scan,
• use "s.Hit" boolean to check if Sensor has hit anything,
• FullBoxCast specific - "s.hits" hold all RaycastHits after you call "s.Scan()"

Why is it useful for?

• We use LineCast on NPCs for collision avoidance,
• FullBoxCast is used as a damage area where NPCs can give damage,
• LineCast is used for Foundations (Building) to scan for ground,
• LineCast is used for Props placement to scan the surface,
• CheckBox is used for all buildable things - to check if there is enough space / volume,
• CurvedCast was used for scanning ground by wall-walking NPCs. They were removed out of game now.

How does it work?

• OnDrawGizmos() calls Scan() every Editor frame,
• some transformation calculations are done,
• Gizmos API is used to draw Gizmos,
• OnDrawGizmos() is not called when you build your game.
• Otherwise, inside game there are never calls to Scan() function. Sensor is static - has no Update() function.

Possible drawbacks

• Sensors are not sensitive to scale of Transform. So if you plan to scale your prefabs, sensors will not,
• Sensors ignore colliders marked as "Triggers",
• Many Sensors will make your Scene view (inside Editor) lag. Rename "OnDrawGizmos()" to "OnDrawGizmosSelected()" - it will draw gizmos only on currently selected prefab.

In action

Licence

MIT licence. Full details in licence.txt file.