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#ifndef MATH_FOR_GRAPHICS_H
#define MATH_FOR_GRAPHICS_H
// math stuff for graphics, from FreePCB
/* Function FindLineSegmentIntersection
* find intersection between line y = a + bx and line segment (xi,yi) to (xf,yf)
* if b > DBL_MAX/10, assume vertical line at x = a
* return false if no intersection or true if intersect
* return coords of intersections in *x1, *y1, *x2, *y2
* if no intersection, returns min distance in dist
*/
bool FindLineSegmentIntersection( double a, double b, int xi, int yi, int xf, int yf,
double * x1, double * y1, double * x2, double * y2, double * dist=NULL );
/* Function FindSegmentIntersections
* find intersections between line segment (xi,yi) to (xf,yf)
* and line segment (xi2,yi2) to (xf2,yf2)
* returns true if intersection found
*/
bool FindSegmentIntersections( int xi, int yi, int xf, int yf,
int xi2, int yi2, int xf2, int yf2 );
/**
* Function TestForIntersectionOfStraightLineSegments
* Test for intersection of line segments
* If lines are parallel, returns false
* If true, returns also intersection coords in x, y
* if false, returns min. distance in dist (may be 0.0 if parallel)
* and coords on nearest point in one of the segments in (x,y)
* @param x1i, y1i, x1f, y1f = integer coordinates of the first segment
* @param x2i, y2i, x2f, y2f = integer coordinates of the other segment
* @param x, y = pointers on 2 integer to store the intersection coordinates (can be NULL)
* @param dist = pointeur on a double to store the dist.
* @return true if intersect.
*/
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 );
/* Function GetClearanceBetweenSegments
* Get clearance between 2 segments
* Returns coordinates of the closest point between these 2 segments in x, y
* If clearance > max_cl, just returns max_cl+1 and doesn't return x,y
*/
int GetClearanceBetweenSegments( int x1i, int y1i, int x1f, int y1f, int w1,
int x2i, int y2i, int x2f, int y2f, 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, 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 );
/* Function GetPointToLineDistance
* Get min. distance from (x,y) to line y = a + bx
* if b > DBL_MAX/10, assume vertical line at x = a
* returns closest point on line in xpp, ypp
*/
double GetPointToLineDistance( double a, double b, int x, int y,
double * xp=NULL, double * yp=NULL );
inline double Distance( double x1, double y1, double x2, double y2 )
{
return hypot( x1 - x2, y1 - y2 );
}
#endif
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