Here's the example code snippet that comes with DBP:
Rem Pick Object
Rem Created: 14/07/2003 18:54:11
rem Init app
sync on : sync rate 60
rem Make floor
make object plain 1,300,300
position object 1,0,-50,0
xrotate object 1,270
rem Make object to drag
make object cube 2,100
set shadow shading on 2
rem Setup camera and light
set point light 0,-100,500,-100
position camera -200,0,-200
point camera 0,0,0
rem main loop
do
rem Call drag subroutine
gosub _drag_object
rem User prompt
center text 320,20,"CLICK AND HOLD OBJECT TO DRAG - RIGHT BUTTON TO ROTATE"
rem Update screen
sync
rem End loop
loop
_drag_object:
if mouseclick()=0 then pickmode=0 : cursorobj=0
mclick=mouseclick()
if mclick>0
if pickmode=0
cursorobj=pick object(mousex(),mousey(),2,2)
if cursorobj>0
pickmode=mclick
pickdistance#=get pick distance()
pickfromx#=get pick vector x()
pickfromy#=get pick vector y()
pickfromz#=get pick vector z()
if pickmode=1
objx#=object position x(cursorobj)
objy#=object position y(cursorobj)
objz#=object position z(cursorobj)
else
objx#=object angle x(cursorobj)
objy#=object angle y(cursorobj)
objz#=object angle z(cursorobj)
pickdiffx#=mousemovey() : pickdiffx#=0
pickdiffy#=mousemovex() : pickdiffy#=0
endif
else
highlightobj=0
endif
endif
if pickmode>0
if pickmode=1
pick screen mousex(),mousey(),pickdistance#
picktox#=get pick vector x()
picktoy#=get pick vector y()
picktoz#=get pick vector z()
pickdiffx#=picktox#-pickfromx#
pickdiffy#=picktoy#-pickfromy#
pickdiffz#=picktoz#-pickfromz#
grid=0
if grid=1
pickdiffx#=int(pickdiffx#/5)*5
pickdiffy#=int(pickdiffy#/5)*5
pickdiffz#=int(pickdiffz#/5)*5
endif
position object cursorobj,objx#+pickdiffx#,objy#+pickdiffy#,objz#+pickdiffz#
else
pickdiffx#=pickdiffx#+mousemovey()
pickdiffy#=pickdiffy#+mousemovex()
grid=0
if grid=1
tpickdiffx#=int(pickdiffx#/22.5)*22.5
tpickdiffy#=int(pickdiffy#/22.5)*22.5
else
tpickdiffx#=pickdiffx#
tpickdiffy#=pickdiffy#
endif
rotate object cursorobj,wrapvalue(objx#-tpickdiffx#),wrapvalue(objy#-tpickdiffy#),objz#
endif
endif
endif
returnQuote: "PICK SCREEN
This command will calculate a relative 3D coordinate from a 2D screen coordinate. The additional Distance parameter
indicates how far into the screen the 3D coordinate is to be calculated. The resulting 3D coordinate is not a world
position, but a relative 3D vector from the current camera position. The world coordinate can be obtained by adding the
camera position to the resulting vector. The resulting vector is generated internally and can be retrieved using the GET
PICK VECTOR commands.
SYNTAX
PICK SCREEN Screen X, Screen Y, Distance"
Basically, the pick screen command will generate 3d co-ordinates relative to the camera position. For exmaple, if the camera is at 10,10,10 and the co-ordinates generated are 1,2,3 then the position will be 11,12,13.
At least I think that's what it means
"Nowadays more and more of our imports are coming from abroad" - George Bush
Formerly David89.
