#include "lineClipper.h"

/*
PONK coords are normalised -1<x<1
this scales everything by 10^4 to allow integer math to work
on shapes at screen res
*/

#define SCALE_FROM_OF 10000
#define SCALE_TO_OF 0.0001

vector <colourPolyline> lineClipper::clip(
	vector <colourPolyline> shapes,
	ofPolyline mask,
	bool invert
	)
{
	//this supports one colour per polyline
	vector <colourPolyline> output;

	if (shapes.size()){

		ofx::Clipper clipper;
		
		mask.scale(SCALE_FROM_OF,SCALE_FROM_OF);

		for (auto& shape: shapes) {

			clipper.Clear();
			clipper.addPolyline(mask, ClipperLib::ptClip);
			shape.scale(SCALE_FROM_OF,SCALE_FROM_OF);
			clipper.addPolyline(shape,ClipperLib::ptSubject);
			vector <ofPolyline> clipped;
			if (invert){
				clipped = clipper.getClippedLines(ClipperLib::ctDifference);
			}else {
				clipped = clipper.getClippedLines(ClipperLib::ctIntersection);
			}

			for (auto& clip: clipped)
	    	{
	    		//clip.simplify(contour_simplify);
	    		clip.scale(SCALE_TO_OF,SCALE_TO_OF);
	        	output.push_back(colourPolyline(clip,shape.getColourAt(0)));
	    	}
	    }	
	}
   
    return output;
}