slow intersect call

[farshizzo]

I can't replicate your problem. I downloaded your model and made the thickness of the wall to 1.0. I then setup a timer that would perform a 180 degree sweep of intersection tests based on the current view position/orientation. I spent a minute navigating through the maze and never got a missed intersection. Here's the script I used to test it out:

import viz
import math
viz.go()

wall = viz.add('wall_thick.wrl')
wall.collideMesh()
wall.disable(viz.DYNAMICS)

viz.MainView.translate(10.5,1.3,-21.0)

def SweepIntersection():

	#Get begin point for intersection test
	begin = viz.MainView.getPosition()
	bx = begin[0]
	by = begin[1]
	bz = begin[2]
	
	#Get point 100 units ahead of viewpoint
	forward = viz.Vector(viz.MainView.getMatrix().getForward(),length=100)
	px = forward[0]
	pz = forward[2]
	
	for deg in range(-90,90):
		
		#Rotate ahead point by deg (Assume no pitch/roll)
		rad = viz.radians(deg)
		x = math.cos(rad)*px - math.sin(rad)*pz 
		z = math.sin(rad)*px + math.cos(rad)*pz
		
		#Calculate end point
		ex = bx + x
		ez = bz + z
		
		#Perform intersection
		info = viz.phys.intersectLine(begin,(ex,by,ez))
		
		#Check if intersection is not valid
		if not info.valid:
			print 'NO INTERSECTION'

vizact.ontimer(0,SweepIntersection)

Does this problem only occur under certain conditions or is it pretty much random?

[pbeeson]

Here is code that works with the Test.wrl I posted earlier. The view is at an angle to the hallway, so a line straight ahead should intersect the wall which is 4.3 meters away. But, this particular line misses the intersection with the closest wall and intersects another wall in the environment (> 10 meters away).

This shows the different results sometimes returned by viz.phys.intersectLine() and viz.intersect().

import viz, math

viz.go()

env = viz.add('Test.wrl')
env.collidemesh()
env.disable(viz.DYNAMICS)

start_pos=[10.5, 1.3, -21.43391, 23.975]

view=viz.get(viz.MAIN_VIEWPOINT)
view.translate(start_pos[0], start_pos[1], start_pos[2])
view.rotate(0,1,0,start_pos[3], viz.BODY_ORI,viz.ABSOLUTE)

def dist(x1,y1,x2,y2):
    return math.sqrt(pow(x1-x2,2)+pow(y1-y2,2))

def timerCallback(num): 
    end_pos=[start_pos[0]+100*math.sin(start_pos[3]*math.pi/180),
             start_pos[1],
             start_pos[2]+100*math.cos(start_pos[3]*math.pi/180)]
    inters_obj = viz.phys.intersectLine(start_pos[0:3], end_pos)
    print inters_obj.intersectPoint
    print dist(inters_obj.intersectPoint[0],inters_obj.intersectPoint[2],
               start_pos[0],start_pos[2])
    inters_obj = viz.intersect(start_pos[0:3], end_pos)
    print ''
    print inters_obj.intersectPoint
    print dist(inters_obj.intersectPoint[0],inters_obj.intersectPoint[2],
               start_pos[0],start_pos[2])
    print '\n\n'

    

viz.callback(viz.TIMER_EVENT, timerCallback)
viz.starttimer(1, 1, -1)

[farshizzo]

I see now, at first I thought the problem was that no intersections were being reported, but the problem is that it doesn't return the closest intersection. Thanks for the test script, the problem should be fixed now.

[pbeeson]

Originally Posted by farshizzo

I see now, at first I thought the problem was that no intersections were being reported, but the problem is that it doesn't return the closest intersection. Thanks for the test script, the problem should be fixed now.

Any way I can get my hands on the fixed code. For "testing" purposes.