edit: This thread might need moved, sorry about that.(adsbygoogle = window.adsbygoogle || []).push({});

Hi, I have ended up on this site a few times after searching various maths issues; it seems to have a good community so I am asking you good people for a little help understanding this.

Tomorrow I have a semi-important maths exam, if I fail it I can resit in 2010 but I would of course rather not have to do that. I am studying game design, so I shall be needing maths a lot more soon.

I missed the part that involved the mathematics of projection, so I need to figure this out fast.

Reading the materials I understood fairly well until it bluntly proposed a problem without before giving a solution to a similar one, so I need a bit of help.

The problem is as follows:

Calculate the orthogonal projection of the points A(3,5,1) and B(-4,2,6) onto the plane -2x+4y-z=3 and determine the equation of the line joining the image points on the plane.

I understand visually what is going on here, but I don't know where to start. The notes talk about the Par i/j/k matrices (none seem to apply here) and the homogeneous coordinate transformation matrix... now I could plug numbers in and see what I come up with, its not like I am going to run out of paper. But I am scared to get lost in this.

Who can help walk me through this? It may take a few posts ^_^

edit:

OK, I think I need to start with:

vector n = (-2,4,-1)

n being the normal

brackets should be vertical... but I don't know how to format it that way

edit:

Ok, I have got this far:

-2(3-2t)+4(5+4t)-(1-t)=3

correct so far? I filled in the values for p=r+tn

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# Orthogonal projection of 2 points onto a plane

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