Given a plane and a 3D point, transform the 3D point to a 2D coordinate along the plane.

Blitz3D Forums/Blitz3D Programming/Given a plane and a 3D point, transform the 3D point to a 2D coordinate along the plane.

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fredborg
 #1
This should get you started:
Global ProjectX#,ProjectY#,ProjectZ#

;
; x,y,z       = Position of the point
; px,py,pz    = A point on the plane
; pnx,pny,pnz = The plane normal
; returns the shortest distance from the point to the plane
;
Function ProjectPointOnPlane#(x#,y#,z#,px#,py#,pz#,pnx#,pny#,pnz#)
	
	Local sb#, sn#, sd#
	sn = - (pnx*(x-px) + pny*(y-py) + pnz*(z-pz))
	sd = (pnx*pnx + pny*pny + pnz*pnz)
	sb = sn / sd

	ProjectX = x + sb * pnx
	ProjectY = y + sb * pny
	ProjectZ = z + sb * pnz
	
	Return Sqr((x - ProjectX)^2 + (y - ProjectY)^2 + (y - ProjectY)^2)
	
End Function

Fredborg