🚀 go-pugleaf

In article <1992Sep1.212308.19369@bmw.mayo.edu>, Kall@Mayo.EDU writes:
> I guess what I was wondering (or dreaming of) is:
> 
> Yes the cursor 'sits over a pixel in the 2D device coordinate space
> of the screen'.  The escape X_DRAWABLE_TO_WC_POINTS
> returns some 3d location based on the X,Y drawable
> location and some Z  value you pass in.  
> 
> Isn't there anyway for Phigs to  figure out  from the
> scene what pixel the 2d cursor is sitting on (i.e. traverse the
> whole scene from Z-min to Z_max  for that 2d X,Y coordinate
> and find out what the 3d WC coordinate is of the pixel that you
> are seeing on the screen.  After traversal  doesn't only one 3d WC coordinate
> deposit that pixel even if structures overlap? 

What you are asking for is PHIGS picking. You need to be using a IN/OUT
workstation type and look at the description of the input functions
for INITIALIZE PICK 3, SET PICK MODE (I recommend event mode), AWAIT EVENT,
and GET PICK.

> 
> 
> ---
> 
> 
> 
> \------------------------------------------------------------\
>  \   Bruce Kall                \  Internet:   Kall@Mayo.edu   \
>   \   Mayo Clinic (Foundation)  \  Phone: (507)-255-4768       \
>    \   Rochester, MN 55905       \                              \
>     \------------------------------------------------------------\
> 

--
 ---		Gary G. Cannon
 ---		Evans & Sutherland
 ---		cannon@dsd.es.com