-- File:	Image_PlanarPixelInterpolation.cdl
-- Created:	Tue Jul 27 18:47:06 1993
-- Author:	Jean Louis FRENKEL
--		<jlf@sparc3>
---Copyright:	 Matra Datavision 1993


class PlanarPixelInterpolation from Image inherits PixelInterpolation from Image

	---Purpose: The class PlanarPixelInterpolation is used to compute a  
	--            SubPixelvalue on non integer Image coordinate
	--          PlanarPixelInterpolation redefined a new method to compute a
	--	      SubPixel value .
	--	    To compute the value of a Image SubPixel, first we look
	--	      for the three nearest Image Pixels .
	--	    Then we compute the plane definition in the 3D space 
	--	      composed by the Image Pixel coordinate and Pixel value 
	--	      on Z axis .
	--	    The SubPixel value is the Z value of ( FX,FY ) point in the
	--	      three nearest Image Pixel defined plane .

uses

    Image 		from Image,
    Pixel       	from Aspect,
    ColorPixel       	from Aspect,
    IndexPixel       	from Aspect,
    DColorImage 	from Image,
    DIndexedImage 	from Image

is

    	Create returns PlanarPixelInterpolation from Image ;
	---Level: Public
    	---Purpose: Create a PlanarPixelInterpolation  object.

	Interpolate( me ; aImage   : Image from Image ;
		          X,Y      : Real  from Standard ;
			  LowerX,LowerY,UpperX,UpperY : Integer from Standard ;
		          RetPixel : in out Pixel from Aspect ) 
		returns Boolean from Standard is redefined ;
	---Level: Public
    	---Purpose: Redefined the method to compute SubPixel's value 
	--	      on non integer Image coordinate.
	--	    LowerX,LowerY,UpperX,UpperY is the Image Min Max, it's used
	--	      to check if the SubPixel coordinate FX,FY is outside of
	--	      image.
	--          Return True  if Interpolation Succes.
	--	    Return False if the SubPixel is out from Image.

	Interpolate( me ; aImage   : DColorImage from Image ;
		          X,Y      : Real  from Standard ;
			  LowerX,LowerY,UpperX,UpperY : Integer from Standard ;
		          RetPixel : in out ColorPixel from Aspect ) 
		returns Boolean from Standard  is redefined;
	---Level: Public
    	---Purpose: Compute SubPixel's value on non integer Image coordinate for
	--	      DColorImage and ColorPixel.
	--	    LowerX,LowerY,UpperX,UpperY is the Image Min Max, it's used
	--	      to check if the SubPixel coordinate FX,FY is outside of 
	--	      image.
	--          Return True  if Interpolation Succes.
	--	    Return False if the SubPixel is out from Image.

	Interpolate( me ; aImage   : DIndexedImage from Image ;
		          X,Y      : Real  from Standard ;
			  LowerX,LowerY,UpperX,UpperY : Integer from Standard ;
		          RetPixel : in out IndexPixel from Aspect ) 
		returns Boolean from Standard  is redefined ;
	---Level: Public
    	---Purpose: Compute SubPixel's value on non integer Image coordinate for
	--	      DIndexedImage and IndexPixel.
	--	    LowerX,LowerY,UpperX,UpperY is the Image Min Max, it's used
	--	      to check if the SubPixel coordinate X,Y is outside of 
	--	      image.
	--          Return True  if Interpolation Succes.
	--	    Return False if the SubPixel is out from Image.

end PlanarPixelInterpolation from Image;