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Vectors.... Nearly there....

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Hi GuysGerrish and Luis and others have tried to explain vectors and distances on vectors, displaying great patience and obviously this still remains a challedge for somebodyI need to understand this and it seems pictures are the only way that I can grasp what is being said. May be because its 3D space(Virtual)http://forums.avsim.com/user_files/9163.jpgThe black line is a polygon like a side of a house and in the real world you want to view it from a very obqiue angle. Of course in designing their is a issue about the more limited view from the cockpit. May be I am geting mixed up with V2's here which I would be more than happy to leave for another day The diagram is attempt to try and explain my understanding, with what I am trying to doI hope somebody feels they can take on this challedge:-hmmm RegardsDave

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Let me give it a try :).You can best see a vector as some sort of arrow that is pointing in a certain direction. Because we have a 3D world in FS the vector has 3 coordinates (x, y and z). The direction in which the arrow points indicates the side of your polygon for example.These vectors are also normalized, that means that the length of them must always be 32767. So this means that (x^2 + y^2 + z^2)^0.5 must be equal to 32767.Now let's go to your image. Let's assume this is the top view of your polygon. The x-axis is pointing to the right and the y-axis to the top. When you now want to indicate that the upper side (the one facing to the top of the image) should be drawn then you need a vector that reads [0 32767 0] for the x y z coordinates (I think SCASM want them in x z y order, so be carefull there). If you want the other side you need [0 -32767 0].Now make it a bit more difficult. Assume you polygon is not along the x-axis, but rotated 45 degrees to the right compared to it. Now the side of it pointing upwards has a vector of [23170 23170 0] and the other side has [-23170 -23170 0]. The value of 23170 is (0.5)^0.5*32767, so that the total length is still 32767.I have tried to illustrate it in the image below.http://home.wanadoo.nl/arno.gerretsen/pics/vector1.gifhttp://home.wanadoo.nl/arno.gerretsen/pics/vector2.gif


Arno

If the world should blow itself up, the last audible voice would be that of an expert saying it can't be done.

FSDeveloper.com | Former Microsoft FS MVP | Blog

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Thanks ArnoIt is the diagram that helps:-jumpy Now in the top diagram the X value would need to be greater than zero to view at an angle, similar has you have indicated in diagram 2, but with the poly still on either X or Y axisI am inching nearer and nearer, with your helpWith this knowledge, I need to experiment further I GuessRegardsDave

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