# Intercepting a line

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I have drawn a line from 0, 0, 0  to 0, 1, 0. So in other words it drawn going upward.

How can I check of some object intercept my line ?

Any detailed description or tutorial?

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What kind of intersection you want to check for?

Some specific like line-plane (line-triangle?)?

Or do you want to know how to properly check for intersection with a big model with many triangles?

Or perhaps you want something like raycasting?

Edited by Waterlimon

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Ohh

I want to check of a Sphere is intercepting my Line.

More then that I don't know. Solutions to the problem?

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Here is how I would do it:

the distance from one point to another is sqrt( (X2 - X1)^2 + (Y2 - Y1)^2 + (Z2 - Z1)^2 )

The equation for your line is  0xi + 1yj + 0zk => yj

So you would want to see if that line ever comes closer to the center of the sphere than the radius of the sphere.  So basically, is there any value of y (for your line) that would make the distance calculation above be less than or equal to R.