B3D Collisions EntityCollided()

Blitz3D Forums/Blitz3D Programming/B3D Collisions EntityCollided()

_PJ_	(Posted 2009) [#1]

I can see now why B3D collision stuff is avoided so much.

I Have set up my collisions with the 'Collisions' command, and givent he entities involved EntityTypes when 'in-game', the collisions appear to work, as (using STOP response) the entities that collide are indeed stopped.

However, when I come to check the collision:

		If (EntityCollided(ShipMesh,CollisionTypeAlien))
			DebugLog "ShipHit "+EntityName(EntityCollided(ShipMesh,CollisionTypeAlien)))
		End If

I have tried this code both before, after and without UpdateWorld and still the debug message never appears :(

Vorderman

(Posted 2009) [#2]

Have you assigned them collision radiuses (assuming you're using sphere->sphere collisions)?

Warner

(Posted 2009) [#3]

Because multiple collisions can occur, it is better to use CountCollisions and CollisionEntity instead:

Graphics3D 800, 600, 0, 2
SetBuffer BackBuffer()

CreateLight()

cam = CreateCamera()
MoveEntity cam, 0, 0, -25

ship = CreateCube()
EntityType ship, 1
EntityAlpha ship, 0.5

EntityParent cam, ship

For i = 0 To 30
	enemy = CreateSphere()
	PositionEntity enemy, Rnd(-25, 25), Rnd(-25, 25), Rnd(-25, 25)
	EntityType enemy, 2
	NameEntity enemy, "ship " + i
Next

MoveMouse 400, 300
MouseXSpeed()
MouseYSpeed()

Collisions 1, 2, 1, 2

Repeat


	TurnEntity ship, -MouseYSpeed(), MouseXSpeed(), 0
	MoveMouse 400, 300
	MoveEntity ship, 0, 0, KeyDown(17)-KeyDown(31)

	UpdateWorld
	
	For i = 1 To CountCollisions(ship)
		DebugLog "hit " + EntityName$(CollisionEntity(ship, i))
		FreeEntity CollisionEntity(ship, i)
	Next
			
	RenderWorld
	Flip
	
Until KeyHit(1)

End

_PJ_	(Posted 2009) [#4]

Yes, Vorderman. they all have collision radii.

Warner - Considering the 'ShipMesh' will only collide with one thing at a time, and I only need to check for ANY collision with an "Alien" type entity, is the count collisions necessary?

Also, I should have mentioned, the "Alien" entities are made with CopyEntity (Although the master has a radius and type set too) Is that likely to be a factor?

Warner

(Posted 2009) [#5]

That should no be an issue:

Graphics3D 800, 600, 0, 2
SetBuffer BackBuffer()

CreateLight()

cam = CreateCamera()
MoveEntity cam, 0, 0, -25

ship = CreateCube()
EntityType ship, 1
EntityAlpha ship, 0.5

EntityParent cam, ship

org = CreateSphere()
EntityRadius org, 1
EntityType org, 2
HideEntity org
	
For i = 0 To 30
	enemy = CopyEntity(org)
	PositionEntity enemy, Rnd(-25, 25), Rnd(-25, 25), Rnd(-25, 25)
	NameEntity enemy, "ship " + i
Next

MoveMouse 400, 300
MouseXSpeed()
MouseYSpeed()

Collisions 1, 2, 1, 2

Repeat


	TurnEntity ship, -MouseYSpeed(), MouseXSpeed(), 0
	MoveMouse 400, 300
	MoveEntity ship, 0, 0, KeyDown(17)-KeyDown(31)

	UpdateWorld
	
	ent = EntityCollided(ship, 2)
	If ent Then
		DebugLog "hit " + EntityName$(ent)
		FreeEntity ent
	End If
			
	RenderWorld
	Flip
	
Until KeyHit(1)

End

_PJ_	(Posted 2009) [#6]

		For iterColls=1 To CountCollisions(ShipMesh)
			DebugLog "Counting: "+iterColls
			Collided=(CollisionEntity(ShipMesh,iterColls))
			If (Collided)
				DebugLog "ShipHit "+EntityName$(Collided)
			End If
		Next

-=-=-=-=

Edit edit edit:
(I made a silly mistake, trying to fid the name of anentitybefore it was even verified to exist!)

Thanks for the help, Warner. The above works fine now I put CountCollisions in. Thank you!