Obtaining Positional Data

[betancourtb82]

I'm using a variation of this duckcourt example, except I increased the speed and shrunk the ball so it looks like a bullet. Unfortunately the crosshair is not too accurate. I don't need pinpoint accuracy, but I would like the "bullet" to "shoot" from the middle of the crosshair. Sometimes when I shoot to the left or right, the bullet comes out from the left or right of the crosshair. I can't think of anyway to adjust this so the bullet comes out from the crosshair no matter what direction I'm shooting. Here is the code for your reference:

def MoveBullet(bullet,elapsed):
	hitObject = 0
	
	#check if bullet is colliding with an object
	for object in collidables:
		
		#perform the collision check with the object
		info = bullet.collidingwith(object,1)
		if info.intersected:
			#set the bullets new vector to the reflection vector
			bullet.vector = viz.Vector(vizmat.ReflectionVector(bullet.vector,info.normalVector))
			
			#create a vector of the normal of the collision
			normal = viz.Vector(info.normalVector)
			
			#Check dot product of velocity and normal
			if bullet.vector * normal <0:
				bullet.vector*= -1
				
			#calculate the rotation vector of the ball
			bullet.rotvector = bullet.vector * rotRight
						
			#if object.isTarget and ball.lastHit != object:
				
			hitObject = object
			
			#play ball bounce sound
			viz.playsound('bounce.wav')
			
			break
	#get the bullet's current position
	pos = bullet.get(viz.POSITION)
	
	#calculate the balls future position based on it's velocity
	futurePos = pos + (bullet.vector * elapsed)
	bullet.translate(futurePos.get())
	
	#rotate the bullet along it's rotation vector
	#bullet.rotate(bullet.rotvector[0],bullet.rotvector[1],ball.rotvector[2],90*elapsed,viz.RELATIVE_WORLD)
	
	#Update the bullet's shadow
	bullet.shadow.translate(futurePos.x,0,futurePos.z)	
			
def mytimer(num):
	
	if num == ANIMATION:
		
		#Calculate elapsed time since last update
		elapsed = viz.elapsed()
		
		#Update each active ball
		for bullet in bullets:
			if bullet.active:
				#Move the ball and check if it has collided with any objects
				MoveBullet(bullet,elapsed)
		
		#Update the crosshair position
		crosshair.translate(viz.mousepos()+[0])
		
	elif num == START_AVATAR:
		global nextAvatar
		#Get the next available duck and start it
		avatar = avatars[nextAvatar]
		walkAvatar(avatar)
		nextAvatar = (nextAvatar + 1) % NUM_AVATARS
		viz.starttimer(START_AVATAR,TIME_BETWEEN_AVATARS)

#Shoot a ball whenever left mousebutton is clicked
vizact.onmousedown(viz.MOUSEBUTTON_LEFT,shootBullet)

#Create callbacks for timer events
viz.callback(viz.TIMER_EVENT,mytimer)

##Start a timer which starts the next available duck
viz.starttimer(START_AVATAR,0.1)

#Start the animation timer, which animates the ball and checks for collisions
viz.starttimer(ANIMATION,0.01,-1)