How to view point of 3D surface under cursor?

eugen1344 shared this question 9 months ago
Answered

Hi. I am using a 3D calculator. I have made a 3D surface, and i want to move my cursor over it and view each coordinate on the surface under my cursor.

Comments (5)

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Hi,

do you want something like this ?

...

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Hi. Your example looks similar to what i want, but not really. I want to define my own surface, move my cursor over it and view the coordinate of each point on my surface

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@Patrick : cursor se traduit par "pointeur de la souris" (sinon c'est slider)

@eugen : if you move your cursor over a surface (sphere for example), you want coordinate of foreground point (and not background) and you want show nothing if your cursor is not over the surface ?

It is possible in 2D, with JavaScript (see here for example) : the position of cursor is one point of the plane

but in 3D, position of cursor define a line...

(perhap's it is possible : position of cursor define a line, and show intersect of this line and your surface

if you knows JavaScript programming...)

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Yep, i want a foreground point. And if my cursor is over the surface, it should either show nothing, or closest point to a cursor.

And it is possible. You can just cast a ray from your screen coordinate directly to the nearest point of the surface. It just requires some math to achieve. For instance, in video games, you can select any 3D object on a screen with your cursor.

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