/** Do line segments (x1, y1)--(x2, y2) and (x3, y3)--(x4, y4) intersect? */
bool DoLineSegmentsIntersect(int x1, int y1, int x2, int y2,
int x3, int y3, int x4, int y4) {
char d1 = ComputeDirection(x3, y3, x4, y4, x1, y1);
char d2 = ComputeDirection(x3, y3, x4, y4, x2, y2);
char d3 = ComputeDirection(x1, y1, x2, y2, x3, y3);
char d4 = ComputeDirection(x1, y1, x2, y2, x4, y4);
return (((d1 > 0 && d2 < 0) || (d1 < 0 && d2 > 0)) &&
((d3 > 0 && d4 < 0) || (d3 < 0 && d4 > 0))) ||
(d1 == 0 && IsOnSegment(x3, y3, x4, y4, x1, y1)) ||
(d2 == 0 && IsOnSegment(x3, y3, x4, y4, x2, y2)) ||
(d3 == 0 && IsOnSegment(x1, y1, x2, y2, x3, y3)) ||
(d4 == 0 && IsOnSegment(x1, y1, x2, y2, x4, y4));
}
/** Do line segments (x1, y1)--(x2, y2) and (x3, y3)--(x4, y4) intersect? */
bool edge_edge_intersect(double x1, double y1, double x2, double y2,
double x3, double y3, double x4, double y4)
{
char d1 = ComputeDirection(x3, y3, x4, y4, x1, y1);
char d2 = ComputeDirection(x3, y3, x4, y4, x2, y2);
char d3 = ComputeDirection(x1, y1, x2, y2, x3, y3);
char d4 = ComputeDirection(x1, y1, x2, y2, x4, y4);
return (((d1 > 0 && d2 < 0) || (d1 < 0 && d2 > 0)) &&
((d3 > 0 && d4 < 0) || (d3 < 0 && d4 > 0))) ||
(d1 == 0 && IsOnSegment(x3, y3, x4, y4, x1, y1)) ||
(d2 == 0 && IsOnSegment(x3, y3, x4, y4, x2, y2)) ||
(d3 == 0 && IsOnSegment(x1, y1, x2, y2, x3, y3)) ||
(d4 == 0 && IsOnSegment(x1, y1, x2, y2, x4, y4));
}
ConnectionSelection::ConnectionSelection(MapFrontend* mf, double mx, double my, int layer)
{
m_admin = NULL;
m_first = true;
m_connectionDescriptor[0].room = NULL;
m_connectionDescriptor[1].room = NULL;
Coordinate c(GLtoMap(mx), GLtoMap(my), layer);
mf->lookingForRooms(this, c, c );
m_connectionDescriptor[0].direction = ComputeDirection(mx, my);
}
void ConnectionSelection::setSecond(MapFrontend* mf, double mx, double my, int layer)
{
m_first = false;
Coordinate c(GLtoMap(mx), GLtoMap(my), layer);
if (m_connectionDescriptor[1].room != NULL)
{
if (m_connectionDescriptor[1].room != m_connectionDescriptor[0].room)
m_admin->releaseRoom(this, m_connectionDescriptor[1].room->getId());
m_connectionDescriptor[1].room = NULL;
}
mf->lookingForRooms(this, c, c );
m_connectionDescriptor[1].direction = ComputeDirection(mx, my);
//if (m_connectionDescriptor[1].direction == ED_UNKNOWN) m_connectionDescriptor[1].direction = ED_NONE;
}
/**
* This routine searches through the specified outline, computes
* a slope for each vector in the outline, and marks each
* vector as having one of the following directions:
* N, S, E, W, NE, NW, SE, SW
* This information is then stored in the outline and the
* outline is returned.
* @param Outline micro-feature outline to analyze
* @param MinSlope controls "snapping" of segments to horizontal
* @param MaxSlope controls "snapping" of segments to vertical
* @return none
* @note Exceptions: none
* @note History: 7/21/89, DSJ, Created.
*/
void FindDirectionChanges(MFOUTLINE Outline,
FLOAT32 MinSlope,
FLOAT32 MaxSlope) {
MFEDGEPT *Current;
MFEDGEPT *Last;
MFOUTLINE EdgePoint;
if (DegenerateOutline (Outline))
return;
Last = PointAt (Outline);
Outline = NextPointAfter (Outline);
EdgePoint = Outline;
do {
Current = PointAt (EdgePoint);
ComputeDirection(Last, Current, MinSlope, MaxSlope);
Last = Current;
EdgePoint = NextPointAfter (EdgePoint);
}
while (EdgePoint != Outline);
} /* FindDirectionChanges */
