kicad/polygon/math_for_graphics.h

// math stuff for graphics, from FreePCB

typedef struct PointTag
{
	double X,Y;
} Point;

typedef struct EllipseTag
{
	Point Center;			/* ellipse center	 */
//	double MaxRad,MinRad;	 /* major and minor axis */
//	double Phi;				/* major axis rotation  */
	double xrad, yrad;		// radii on x and y
	double theta1, theta2;	// start and end angle for arc 
} EllipseKH;

const CPoint zero(0,0);

class my_circle {
public:
	my_circle(){};
	my_circle( int xx, int yy, int rr )
	{
		x = xx;
		y = yy;
		r = rr;
	};
	int x, y, r; 
};

class my_rect {
public:
	my_rect(){};
	my_rect( int xi, int yi, int xf, int yf )
	{
		xlo = min(xi,xf);
		xhi = max(xi,xf);
		ylo = min(yi,yf);
		yhi = max(yi,yf);
	};
	int xlo, ylo, xhi, yhi; 
};

class my_seg { 
public:
	my_seg(){};
	my_seg( int xxi, int yyi, int xxf, int yyf )
	{
		xi = xxi;
		yi = yyi;
		xf = xxf;
		yf = yyf;
	};
	int xi, yi, xf, yf; 
};

// math stuff for graphics
BOOL Quadratic( double a, double b, double c, double *x1, double *x2 );
void DrawArc( CDC * pDC, int shape, int xxi, int yyi, int xxf, int yyf, BOOL bMeta=FALSE );
void RotatePoint( CPoint *p, int angle, CPoint org );
void RotateRect( CRect *r, int angle, CPoint org );
int TestLineHit( int xi, int yi, int xf, int yf, int x, int y, double dist );
int FindLineIntersection( double a, double b, double c, double d, double * x, double * y );
int FindLineSegmentIntersection( double a, double b, int xi, int yi, int xf, int yf, int style, 
				double * x1, double * y1, double * x2, double * y2, double * dist=NULL );
int FindSegmentIntersections( int xi, int yi, int xf, int yf, int style, 
								 int xi2, int yi2, int xf2, int yf2, int style2,
								 double x[]=NULL, double y[]=NULL );
BOOL FindLineEllipseIntersections( double a, double b, double c, double d, double *x1, double *x2 );
BOOL FindVerticalLineEllipseIntersections( double a, double b, double x, double *y1, double *y2 );
BOOL TestForIntersectionOfStraightLineSegments( int x1i, int y1i, int x1f, int y1f, 
									   int x2i, int y2i, int x2f, int y2f,
									   int * x=NULL, int * y=NULL, double * dist=NULL );
void GetPadElements( int type, int x, int y, int wid, int len, int radius, int angle,
					int * nr, my_rect r[], int * nc, my_circle c[], int * ns, my_seg s[] );
int GetClearanceBetweenPads( int type1, int x1, int y1, int w1, int l1, int r1, int angle1,
							 int type2, int x2, int y2, int w2, int l2, int r2, int angle2 );
int GetClearanceBetweenSegmentAndPad( int x1, int y1, int x2, int y2, int w,
								  int type, int x, int y, int wid, int len, 
								  int radius, int angle );
int GetClearanceBetweenSegments( int x1i, int y1i, int x1f, int y1f, int style1, int w1,
								   int x2i, int y2i, int x2f, int y2f, int style2, int w2,
								   int max_cl, int * x, int * y );

/** Function GetPointToLineSegmentDistance
 * Get distance between line segment and point
 * @param x,y = point
 * @param	xi,yi and xf,yf = the end-points of the line segment
 * @return the distance
 */
double GetPointToLineSegmentDistance( int x, int y, int xi, int yi, int xf, int yf );

double GetPointToLineDistance( double a, double b, int x, int y, double * xp=NULL, double * yp=NULL );
BOOL InRange( double x, double xi, double xf );
double Distance( int x1, int y1, int x2, int y2 );
int GetArcIntersections( EllipseKH * el1, EllipseKH * el2, 
						double * x1=NULL, double * y1=NULL, 
						double * x2=NULL, double * y2=NULL );						
CPoint GetInflectionPoint( CPoint pi, CPoint pf, int mode );

// quicksort (2-way or 3-way)
void quickSort(int numbers[], int index[], int array_size);
void q_sort(int numbers[], int index[], int left, int right);
void q_sort_3way( int a[], int b[], int left, int right );