Forced Perspective with 3D Graphics
Submitted by Lanowen on Sun, 05/24/2015 - 02:15A friend asked me about this problem, on how to calculate the distance an object needs to be from the camera to appear a certain height on the screen.
Easy Solution:
The solution is simpler when dealing with an object centered in the in the screen where a right angle can be created from the camera to the object.

Fig. 1: right angle triangle diagram.
Solving the triangle in Fig.1:
tan(θ2)=h2d