trigo.h 3.95 KB
/**
 * @file trigo.h
 */

#ifndef TRIGO_H
#define TRIGO_H


/*
 * Calculate the new point of coord coord pX, pY,
 * for a rotation center 0, 0, and angle in (1 / 10 degree)
 */
void RotatePoint( int *pX, int *pY, double angle );

/*
 * Calculate the new point of coord coord pX, pY,
 * for a rotation center cx, cy, and angle in (1 / 10 degree)
 */
void RotatePoint( int *pX, int *pY, int cx, int cy, double angle );

/*
 * Calculates the new coord point point
 * for a rotation angle in (1 / 10 degree)
 */
static inline void RotatePoint( wxPoint* point, double angle )
{
    RotatePoint( &point->x, &point->y, angle );
}

/*
 * Calculates the new coord point point
 * for a center rotation center and angle in (1 / 10 degree)
 */
void RotatePoint( wxPoint *point, const wxPoint & centre, double angle );

void RotatePoint( double *pX, double *pY, double angle );

void RotatePoint( double *pX, double *pY, double cx, double cy, double angle );

/* Return the arc tangent of 0.1 degrees coord vector dx, dy
 * between -1800 and 1800
 * Equivalent to atan2 (but faster for calculations if
 * the angle is 0 to -1800, or + - 900
 */
int ArcTangente( int dy, int dx );

/**
 * Function DistanceTest
 * Calculate the distance from mouse cursor to a line segment.
 * @return  False if distance > threshold or true if distance <= threshold.
 */
bool DistanceTest( int seuil, int dx, int dy, int spot_cX, int spot_cY );

//! @brief Compute the distance between a line and a reference point
//! Reference: http://mathworld.wolfram.com/Point-LineDistance2-Dimensional.html
//! @param linePointA Point on line
//! @param linePointB Point on line
//! @param referencePoint Reference point
double DistanceLinePoint( wxPoint linePointA, wxPoint linePointB, wxPoint referencePoint );

//! @brief Euclidean norm of a 2D vector
//! @param vector Two-dimensional vector
//! @return Euclidean norm of the vector
double EuclideanNorm( wxPoint vector );

//! @brief Vector between two points
//! @param startPoint The start point
//! @param endPoint The end point
//! @return Vector between the points
wxPoint TwoPointVector( wxPoint startPoint, wxPoint endPoint );

//! @brief Test, if two points are near each other
//! @param pointA First point
//! @param pointB Second point
//! @param threshold The maximum distance
//! @return True or false
bool HitTestPoints( wxPoint pointA, wxPoint pointB, double threshold );

//! @brief Determine the cross product
//! @param vectorA Two-dimensional vector
//! @param vectorB Two-dimensional vector
int CrossProduct( wxPoint vectorA, wxPoint vectorB );


/**
 * Function TestSegmentHit
 * test for hit on line segment
 * i.e. cursor within a given distance from segment
 * @param aRefPoint = cursor (point to test) coords
 * @param aStart is the first end-point of the line segment
 * @param aEnd is the second end-point of the line segment
 * @param aDist = maximum distance for hit
*/
bool TestSegmentHit( wxPoint aRefPoint, wxPoint aStart, wxPoint aEnd, int aDist );

/**
 * Function GetLineLength
 * returns the length of a line segment defined by \a aPointA and \a aPointB.
 * @return Length of a line.
 */
double GetLineLength( const wxPoint& aPointA, const wxPoint& aPointB );


/*******************/
/* Macro NEW_COORD */
/*******************/

/* Calculate coordinates to rotate around an axis
 *           coord:  xrot = y + x * sin * cos
 *                   yrot = y * cos - sin * x
 *           either: xrot = (y + x * tg) * cos
 *                   yrot = (y - x * tg) * cos
 *
 * Cosine coefficients are loaded from a trigonometric table by 16 bit values.
 */
#define NEW_COORD( x0, y0 )                       \
    do {                                          \
        int itmp;                                 \
        itmp = x0;                                \
        x0 = x0 + (int)( y0 * tg );               \
        y0 = y0 - (int)( itmp * tg );             \
        x0 = ( x0 * cosinus ) >> 8;               \
        y0 = ( y0 * cosinus ) >> 8;               \
    } while( 0 );


#endif