--[[  
      Absolute Value Viewshader 
	  v1.01 
	  Sep 3 2009
--]]	

--[[

 Written by Chad Capeland (ccapeland[REMOVE-ME]@anatomicaltravel.com)
 Copyright (c) 2009 Anatomical Travelogue LLC 
 (http://www.anatomicaltravel.com/research)

 The authors hereby grant permission to use, copy, and distribute this
 software and its documentation for any purpose, provided that existing
 copyright notices are retained in all copies and that this notice is
 included verbatim in any distributions. Additionally, the authors grant
 permission to modify this software and its documentation for any
 purpose, provided that such modifications are not distributed without
 the explicit consent of the authors and that existing copyright notices
 are retained in all copies. 

 IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
 DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING
 OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY DERIVATIVES
 THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE POSSIBILITY OF
 SUCH DAMAGE. 

 THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
 THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND THE AUTHORS AND
 DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT,
 UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 

--]]

shader = 
[[
struct AbsVSFuse : ViewShader
{
	ViewShader source;									// need this line

	void ShadePixel(inout FuPixel f)
	{
		source.ShadePixel(f);							// get source pixel

		f.Color.rgba = abs(f.Color.rgba);		// absolute value
	}
};
]]

-- regnode
FuRegisterClass("AbsVSFuse", CT_ViewLUTPlugin, {		-- ID must be unique
	REGS_Name = "Absolute Value ViewShader",
	})
	
-- Called on creation. Add any controls here.
function Create()
end

-- This is called when the shader is created
-- img may be nil
function SetupShader(req, img)
	local vs = ViewShader("AbsVSFuse", shader);	-- pass struct name and shader string
	return vs;
end

-- This is called every display refresh
-- img may be nil
function SetupParams(req, vs, img)
	return true;
end