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How to get 2D coordinate of point located in 3D-world?
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@duyizhuo

Posts: 1

NGLNewbie

Thu, Jul 18 2013


I tried to use projection and view matrix of the camera to do this, but it seems comes out the wrong answer.


NGLmat4 tmp1;
nglMatrixMultiply(*(camera.matrixView),*(camera.matrixProjection), tmp1);
NGLvec4 a = nglVec4ByMatrix(pos, tmp1);


What's wrong with my way doing this?
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@dineybomfim

Posts: 571

NGLAdmin

Thu, Jul 18 2013


In response to: @duyizhuo

Are you looking for 2D coordinate in which space? In relation to the device's screen?

If so, there are a much more work involved in this. You must search for a technique called "ray cast" or other ray techniques.
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