6DoF Demo

Well I figured since I couldn't get the quat rotations working then I'd try to use some built in commands. Come to find out it was exactly what I was looking for. My first big hurdle was being able to define a thrust vector (along the z-axis) and being able to apply thrust to it no matter what orientation the aircraft was at. I had a feeling TFormNormal looked promising...and it was just what the doctor ordered.

Here's my labor. Thrust applied to the z-axis (0,0,1) no matter what orientation the object is at. It's a first step towards making a decent flight sim. Test it out. I know it's not much but at least I'm getting there. With this accomplishment, I'm kicking Tandem Fighters up to 2% complete!

From here on out it should get easier...well...let me get another beer.

;6DoF Demo
;by Chroma

Graphics3D 800,600,32,2
SetBuffer BackBuffer()

camera = CreateCamera()
PositionEntity camera,0,15,-15
light = CreateLight()

;Replace with your airplane
cube = CreateCube()
RotateEntity cube,0,0,0
PointEntity camera,cube

;Vectors
vOri.Vec3 = New Vec3	;Orientation
vFor.Vec3 = New Vec3	;Total Forces acting on the object
vAcc.Vec3 = New Vec3	;Acceleration (a=f/m)
vVel.Vec3 = New Vec3	;Velocity
vPos.Vec3 = New Vec3	;Position

;Object mass
Local mass# = 10

;Gravity
g# = 9.8

;Initial thrust
Local thrust# = 10.0

;Main Loop
While Not KeyHit(1)
Cls

;Crude Controls
If KeyDown(200) TurnEntity cube,1,0,0
If KeyDown(208) TurnEntity cube,-1,0,0
If KeyDown(203) TurnEntity cube,0,0,1
If KeyDown(205) TurnEntity cube,0,0,-1

;Reset Forces to Zero
Vec3_Set( vFor )

;Set Thrust Vector Forward
TFormNormal 0,0,1,cube,0

;Get Transformed Thrust Vector
Vec3_Set( vOri, TFormedX#(), TFormedY#(), TFormedZ#() )

;Apply Thrust
Vec3_MulScalar(vFor, vOri, Thrust)

;Gravity
;vFor\y = vFor\y - g * mass

;Apply Physics
Vec3_DivScalar(vAcc, vFor, mass)
Vec3_Add(vVel,vVel,vAcc,0.016)
Vec3_Add(vPos,vPos,vVel,0.016)
PositionEntity cube,vPos\x,vPos\y,vPos\z

UpdateWorld
RenderWorld

;Debug
Text 5,5,"XRot: "  + vOri\x
Text 5,25,"YRot: " + vOri\y
Text 5,45,"ZRot: " + vOri\z

Flip
Wend
EndGraphics
End


;Bare Vector Guts
Type Vec3
	Field x#,y#,z#
End Type

Function Vec3_Set(a.Vec3, x#=0, y#=0, z#=0)
	a\x = x
	a\y = y
	a\z = z
End Function

Function Vec3_Add(res.Vec3, a.Vec3, b.Vec3, time# = 1.0)
	res\x = a\x + b\x * time
	res\y = a\y + b\y * time
	res\z = a\z + b\z * time
End Function

Function Vec3_Mul(res.Vec3, a.Vec3, b.Vec3)
	res\x = a\x * b\x
	res\y = a\y * b\y
	res\z = a\z * b\z
End Function

Function Vec3_MulScalar(res.Vec3, a.Vec3, scalar#)
	res\x = a\x * scalar
	res\y = a\y * scalar
	res\z = a\z * scalar
End Function

Function Vec3_DivScalar(res.Vec3, a.Vec3, scalar#)
	res\x = a\x / scalar
	res\y = a\y / scalar
	res\z = a\z / scalar
End Function

man i'd thought you have support of 6DoF for TrackIR with Blitz3d when i read your title ;)

stupid me thought, DOF would stay for DepthOfField...stupid, i know ;)


hm, but what exactly is this code meant to do? i see a small cube slowly flying out of view...? o.O

Apparently my choice of title sucks lol.

Use the arrow keys to turn the cube. The thrust always emits along the cube's local z-axis no matter what the global orientation. That was what I've been trying to do with quaternions but, and I still have no clue why, I couldn't get it working.

Nothing wrong with the title if you ask me but I am surprised you hadn't discovered the wonders of the tform commands before now.

I can't stress enough how useful they've been in building my 2d and 3d physics engines.

Good luck with the flight sim - you'll definately need it! ;)

Stevie

I blame everquest! But now I have nothing to do except code. :)