finding a position in a figure...

I´m quiet new to OpenGL. I wonder if there is a easy way to figure out the coordinates within a figure, if I make a click with the mouse in the figure. Let´s say I´d like to paint a sphere…


by figure do you mean your window? or something within the window?

I want to insert a figure of a head in my OpenGL window and Id like to paint on this head. Say Id like to add a intensity map over the figure of the head… and also be able to add points to the figure of the head…

get it?? ; )


You can do it using selection buffer.
But you have to assign names to each polygon.
If “head” is round, it can be done using simple math. OpenGL can give you a world coordinates of point under cursor.