WorldViz User Forum  

Go Back   WorldViz User Forum > Vizard

Reply
 
Thread Tools Rate Thread Display Modes
  #1  
Old 11-09-2015, 01:21 PM
vserchi vserchi is offline
Member
 
Join Date: Sep 2013
Posts: 7
Road Animation Path

Hi,
I am trying to animate infinitely a sequence of elements using animation paths. I want to be able to update the speed of the elements but I want them always at the same distance one from the others. My goal is to have a road translating toward a subject walking on a treadmill and to update the speed of translation according to the subject's speed. I took as example the code implemented into the Vizard examples folder. I have a first set of elements that translate and stop out of the view of the subject and a set of permanent elements that make an infinite loop of the animation path their are linked to. My problem is that my permanent elements either superimpose or let space between them (when the first element starts the loop of the animation again). I am using animation path events to animate the different animation paths I have.
I am probably wrongly implementing either the animation paths or the animation events. Here is the code I wrote. Can you tell me how can I improve it or if there is any other solution that I can implement?

Code:
import viz
import vizinfo
import vizact

viz.setMultiSample(4)
viz.fov(60)
viz.go()

#Add the ground plane
ground = viz.addChild('ground.osgb')

#Move the viewpoint back
viz.MainView.move([ 0, 0, -4])

#Initialize an array of control points
positions = [[ 2, 0, 0], [ 1, 0, 0], [ 0, 0, 0], [ -1, 0, 0], [ -2, 0, 0], [ -3, 0, 0], [ -4, 0, 0]]

for i in range(0, len(positions)):	
	# Define the first sequence of elements which will disappear after 
	# their animation
	viz.startlayer(viz.QUADS) 
	viz.texCoord( 0, 1)
	viz.vertex(  -0.5, .005, -0.5)
	viz.texCoord( 1, 1)
	viz.vertex(  -0.5, .005, 0.5)
	viz.texCoord( 1, 0)
	viz.vertex(  0.5, .005, 0.5)
	viz.texCoord( 0, 0)
	viz.vertex(0.5, .005, -0.5)
	
	exec('QUAD' + str(i) + ' = viz.endLayer()')
	exec('BALL' + str(i) + '= viz.addChild("beachball.osgb")')
	exec('PATH' + str(i) + ' = viz.addAnimationPath()')
	
	positions1 = positions[i :]
	
	for x, pos in enumerate(positions1):
		exec('PATH' + str(i) + '.addControlPoint( x + 1, pos = pos)')
	
	# Add a control point on the second element of PATH0
	if (i == 0):
		exec('PATH'  + str(i) + '.addEventAtControlPoint("positions", 1)')
	
	#Link BALL and QUAD to PATH and play PATH
	viz.link(eval('PATH' + str(i)) , eval('BALL' + str(i)))
	viz.link(eval('PATH' + str(i)) , eval('QUAD' + str(i)))
	exec('PATH'  + str(i) + '.play()')
	
	
	#Definition of permanent elements
	viz.startlayer(viz.QUADS) 
	viz.texCoord( 0, 1)
	viz.vertex(  -0.5, .005, -0.5)
	viz.texCoord( 1, 1)
	viz.vertex(  -0.5, .005, 0.5)
	viz.texCoord( 1, 0)
	viz.vertex(  0.5, .005, 0.5)
	viz.texCoord( 0, 0)
	viz.vertex(0.5, .005, -0.5)
	
	exec('quad' + str(i) + ' = viz.endLayer()')
	exec('ball' + str(i) + '= viz.addChild("beachball.osgb")')
	exec('path' + str(i) + ' = viz.addAnimationPath()')
	exec('positions1' + str(i) + '= positions')
	
	for x, pos in enumerate(eval('positions1' + str(i) )):
		#Add a ball at each control point and make it
		#semi-transparent, so the user can see where the
		#control points are
		b = viz.addChild('beachball.osgb',cache=viz.CACHE_CLONE)
		b.setPosition(pos)
		b.alpha(0.2)
		
		exec('path' + str(i) + '.addControlPoint( x + 1, pos = pos)')
	
	#Set the initial loop mode to circular
	exec('path' + str(i) + '.setLoopMode(viz.ON)')
	
	# Add a control point at the second control point of path-i
	exec('path'  + str(i) + '.addEventAtControlPoint("positions", 1)')
	
	# Link the ball  and the quad to the path
	viz.link(eval('path' + str(i)) , eval('ball' + str(i)))
	viz.link(eval('path' + str(i)) , eval('quad' + str(i)))
	
	
def onPointReached():
	# Trigger the start of the animation of path0
	path0.play()
	
# Setup callbacks for the PATH0 events	
vizact.onPathEvent(PATH0, "positions", onPointReached)

index = 1
def onPointReached1():
	# Trigger the start of the following animation path
	global index
	eval('path' + str(index) + '.play()')
	eval('path' + str(index - 1) + '.clearEvents()')
	index += 1
	
# Setup callbacks for the path-i events	
for i in range( 0, len(positions) - 1):
	vizact.onPathEvent(eval('path' + str(i)) , "positions", onPointReached1)

#Setup path control panel
controlPanel = vizinfo.InfoPanel(text = None, title = 'Settings', icon = False)
slider_speed = controlPanel.addLabelItem('Speed', viz.addSlider())
slider_speed.set(0.1)

def changeSpeed(pos):
	#Adjust the speed of the animation path
	for i in range(0, len(positions)):
		eval('path' + str(i) + '.setSpeed( pos * 10 )')
		eval('PATH' + str(i) + '.setSpeed( pos * 10 )')

#Setup callbacks for slider events
vizact.onslider(slider_speed, changeSpeed)
Reply With Quote
  #2  
Old 11-10-2015, 04:04 PM
Jeff Jeff is offline
WorldViz Team Member
 
Join Date: Aug 2008
Posts: 2,383
To get coding suggestions on the forum, it's best to create the simplest possible example that shows the issue.
Reply With Quote
  #3  
Old 11-11-2015, 07:38 AM
vserchi vserchi is offline
Member
 
Join Date: Sep 2013
Posts: 7
Sorry my bad. Here is the simplest example I could think about. Even if I am interested only in the motion of the quads, I added also balls to show that my elements superimpose. When I attach a texture to the quads and they superimpose, the resulting effect is a flashing of the overlaid part. Do you have any suggestion?

Code:
import viz
import vizinfo
import vizact

viz.setMultiSample(4)
viz.fov(60)
viz.go()

#Add the ground plane
ground = viz.addChild('ground.osgb')

#Move the viewpoint back
viz.MainView.move([ 0, 0, -4])

#Initialize an array of control points
positions = [[ 2, 0, 0], [ 1, 0, 0], [ 0, 0, 0], [ -1, 0, 0], [ -2, 0, 0], [ -3, 0, 0], [ -4, 0, 0]]

#Define a variable to store the animation paths relative to each element
PATH = []

for i in range(0, len(positions)):	
	viz.startlayer(viz.QUADS) 
	viz.texCoord( 0, 1)
	viz.vertex(  -0.5, .005, -0.5)
	viz.texCoord( 1, 1)
	viz.vertex(  -0.5, .005, 0.5)
	viz.texCoord( 1, 0)
	viz.vertex(  0.5, .005, 0.5)
	viz.texCoord( 0, 0)
	viz.vertex(0.5, .005, -0.5)
	
	quad = viz.endLayer()
	ball= viz.addChild("beachball.osgb")
	
	exec('path' + str(i) + ' = viz.addAnimationPath()')
	PATH.append(eval('path' + str(i)))
	
	for x, pos in enumerate(positions):
		#Add a ball at each control point and make it
		#semi-transparent, so the user can see where the
		#control points are
		b = viz.addChild('beachball.osgb',cache=viz.CACHE_CLONE)
		b.setPosition(pos)
		b.alpha(0.2)
		
		PATH[i].addControlPoint( x + 1, pos = pos)
	
	#Set the initial loop mode to circular
	PATH[i].setLoopMode(viz.ON)
	
	# Add a control point at the second control point of path-i
	PATH[i].addEventAtControlPoint("positions", 1)
	
	# Link the ball  and the quad to the path
	viz.link( PATH[i], ball)
	viz.link( PATH[i], quad)
	
index = 1
def onPointReached1():
	# Trigger the start of the following animation path
	global index
	
	if index < len(PATH):
		PATH[index].play()

	index += 1
	
# Setup callbacks for each animation path
for i in range( 0, len(PATH) - 1):
	vizact.onPathEvent( PATH[i], "positions", onPointReached1)

#Play the first animation path
PATH[0].play()

#Setup path control panel
controlPanel = vizinfo.InfoPanel(text = None, title = 'Settings', icon = False)
slider_speed = controlPanel.addLabelItem('Speed', viz.addSlider())
slider_speed.set(0.1)

def changeSpeed(pos):
	#Adjust the speed of the animation path
	for i in range(0, len(PATH)):
		PATH[i].setSpeed( pos * 10 )

#Setup callbacks for slider events
vizact.onslider(slider_speed, changeSpeed)
Reply With Quote
  #4  
Old 11-11-2015, 04:53 PM
Jeff Jeff is offline
WorldViz Team Member
 
Join Date: Aug 2008
Posts: 2,383
If you're just interested in animating the textures another way of doing this is to modify the texture coordinates over time. See the 'applying textures example' in Teacher in a Book available from our downloads page. If you have 3ds Max, you could animate the textures, export the animation with the OSG model, and control the animation speed in Vizard.
Reply With Quote
  #5  
Old 11-12-2015, 09:29 AM
vserchi vserchi is offline
Member
 
Join Date: Sep 2013
Posts: 7
Ok I will try that but there still something I do not understand. The texture has to be applied to something, right? In my case this something would be a sequence of quads on the ground. I want to simulate a road translating on the ground. To do that I define an animation path for each quad composing my road. I link each animation path to the others and play them (using viz.FOREVER as attribute to my animation path). If the quads superimpose or separate during the time my script runs, also the texture will do that. Is that correct?
Reply With Quote
Reply

Tags
animation, events, path, road, speed

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Clarification on CAL3D Avatar Animation in Vizard shivanangel Vizard 2 11-22-2010 07:16 AM
positions on animation path whj Vizard 3 10-27-2009 01:21 PM
Start_position on animation path ptjt255 Vizard 1 08-24-2009 11:40 AM
Problems with interaction of vizact.turn and animation path Enlil Vizard 3 11-24-2008 04:23 PM
speed on animation path whj Vizard 8 11-17-2008 07:41 PM


All times are GMT -7. The time now is 02:33 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Copyright 2002-2018 WorldViz LLC