Placing objects in the world

[jkndmiththinda]

Hi I'm new to JPCT engine and find it great and very interesting. I need to create a screen with 3d icons and text captions and i want these icons to be spread evenly on the screen, regardless the screen size of the device. I used blitting to position the captions as desired. But i have trouble positioning the corresponding 3d icons, I don't understand how to correlate screen size with the object translation units. Could you please explain how to do this? Once again, thank you very much for sharing this great engine!

[EgonOlsen]

It's a basic perspective projection, but there's no rule that says "50 units in world space to the left ends up at pixel 50/60 on a 800*480 display. It depends on a lot of things like fov, camera position, scale etc.

However, maybe this method can help to find a solution: http://www.jpct.net/jpct-ae/doc/com/threed/jpct/Interact2D.html#reproject2D3DWS(com.threed.jpct.Camera, com.threed.jpct.FrameBuffer, int, int)

[jkndmiththinda]

Dear EgonOslen,

Thank you very much for the reply. I managed to get the task done using the reference you gave. Again, thanks for sharing this great engine with the developer community.