I have a problem on how to represent or compute the rendering of some 3D handles in my game
My goal is to render something at the side of a graphical plane (not infinite) based on the right vector of the camera.
see this
In this drawing the camera is at the right side of the object,
I need to draw the two circles at the edge of the plane based on where my camera right vector is.
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If I rotate the camera to say infront of the object it will look like this
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Same if the camera is at the side
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by the looks of it it is easy.
as i just need to get the look vector by subtracting camera position and object position, and cross vector with object's Up vector and I can get the right vector and display.
my problem is, if the Plane is tilted or rotated, Example like this
(front view)
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if the above is front view and the plane is rotated in Z axis, i need to get the correct position of where to draw the two circles. I can get the ‘direction’ of this plane though, as this plane was drawn from a line and extruded so i have its normal, I just need to project the computed right vector based from the one i described above to this plane so that when i rotate the points are always inside that plane.
any one can help?