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Projectile with zero speed not giving a Hit Normal

I made a basic Projectile following a simple tutorial.
Its components are :



- Projectile
- [Root] Sphere1
   - PaperFlipbook1


This projectile has a speed, and when fired it moves correctly and collides with my Enemy. In the projectile BeginOverlap gets called with “Sweep Result” giving me an Impact Normal.

I then created a child of this projectile and gave it a zero speed, and zero gravity - so it would just spawn and hang there for a second.
I realised though, with this inheritance I cant change properties in the Components window? So on Begin Play I do : Stop Movement() and Set Enabled Gravity (false)

When this projectile spawns, it hits the Enemy, but the Sweep Result gives a vec(0,0,0) on all the Normals
As soon as I un hook the “stop move”, it fires and gives me the Normals

Is this correct behaviour?

If the hit normal is the direction that the object got hit, and it was not moving when it ran into the other object, it would seem that it would have to have a length of zero.

So two objects overlap, but because they arent moving, the Hit doesn’t generate a Normal?