Re: [osg-users] Extend a Line

2012-09-05 Thread Sebastian Messerschmidt

Hello Dan,

I don't really see what your question has to do with OSG or I simply 
don't understand the question.

Here's some interpretation:
You have two coordinate frames in 3d space.
Now you want a the second frame to be aligned to the first one.
Position only is easy. Construct a vector between the two positions and 
normalize it.
Now multiply this vector with the desired distance and add it to the 
first position.


But this won't bring you _behind_ the first. For this you have to take 
the direction vector of the first plane and do the same trick as above:
Normalize it, and add it (negated) to the first position scaled by your 
desired distance. This point will give you your second position.

I guess you will have to adapt the seconds orientation as well.

A general advice though:
Before you start building a flight simulator you should really learn the 
maths in 3d in order to understand OSG and the simulation stuff.


cheers
Sebastian



Hi,

I am making a very simple flight simulator and have a plane location and a 
second chase plane location

I do not want the chase plane to get too close to the target plane.

I also do not want it to get too far away from the target plane.

How do I extend a line in 3D space?  If I can extend the points below I can 
always have the chase plane a fixed distance behind

targetPos = 3, 3, 3 * trailPos = 6, 7, 3

Thank you for help to a simple question

Dan

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Read this topic online here:
http://forum.openscenegraph.org/viewtopic.php?p=49758#49758





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[osg-users] Extend a Line

2012-09-04 Thread Dan Marshal
Hi,

I am making a very simple flight simulator and have a plane location and a 
second chase plane location  

I do not want the chase plane to get too close to the target plane.

I also do not want it to get too far away from the target plane.

How do I extend a line in 3D space?  If I can extend the points below I can 
always have the chase plane a fixed distance behind

targetPos = 3, 3, 3 * trailPos = 6, 7, 3

Thank you for help to a simple question

Dan

--
Read this topic online here:
http://forum.openscenegraph.org/viewtopic.php?p=49758#49758





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