Mark's chasecam

Blitz3D Forums/Blitz3D Programming/Mark's chasecam

slenkar

(Posted 2005) [#1]

I am using Mark's chasecam code, but I want 'markio' to stay the same distance from the camera no matter how fast he is going,

so I changed this line:
TranslateEntity entity_camera,dx*.1,dy*.1,(dz*.1)+speed

but the camera didnt centre itself properly and ended up at a strange angle,
can anyone help?

RiverRatt

(Posted 2005) [#2]

I just tried it and the camera worked fine. Idid not see a angle. Are you sure you did not change something else?

slenkar

(Posted 2005) [#3]

Function CreateChaseCam(entity_camera,entity )

EntityParent(entity_camera,0)
camera_target=CreatePivot( entity )
heading=CreatePivot( entity )
PositionEntity camera_target,0,4,-10
PositionEntity heading,0,4,20

End Function

Function UpdateChaseCam(entity_camera,speed#)	
	dx#=EntityX(camera_target,True)-EntityX(entity_camera,True)
	dy#=EntityY(camera_target,True)-EntityY(entity_camera,True)
	dz#=EntityZ(camera_target,True)-EntityZ(entity_camera,True)
	
TranslateEntity entity_camera,dx*.1,dy*.1,(dz*.1)+speed

PointEntity entity_camera,heading,EntityRoll(piloted_ship)

End Function

I am using a simplified version,
when I add +speed the camera doesnt centre itself properly
but when I leave it out it centres itself normally

DJWoodgate

(Posted 2005) [#4]

In effect that *.1 bit for each axis is the speed the camera will translate towards the target in that axis. So change that. It is not an absolute speed of course, it divides the distance down, so it will take progessively smaller steps, a bit like the rate parameter on aligntovector. So just remove the *.1 from dz*.1 to keep the Z distance constant.

You could have the camera transition at an absolute rate if you prefer. To do that get the distance...
dist#=sqr(dx*dx+dy*dy+dz*dz)
Then if the distance is greater than the speed divide each component by the distance (normalising the vector so the sum of the components will be one) and then multiply each component by the speed...
if dist>speed Then
dx=dx/dist*speed
dy=dy/dist*speed
dz=dz/dist*speed
Endif
Then translate by dx,dy,dz

Not tested though, so it may need some of that old fine tuning.

slenkar

(Posted 2005) [#5]

thanks Ratt and DJ