public static bool PointOnLine(Vector point, Line line)
{
Vector a, b;
Vector ap = Geom.Sub(point, line.a);
Vector ab = Geom.Sub(line.b, line.a);
// colinear check
if (Geom.Mul(ap, ab) != 0)
{
return(false);
}
// check x
if (line.a.x < line.b.x)
{
a = line.a;
b = line.b;
}
else
{
a = line.b;
b = line.a;
}
if (point.x < a.x || point.x > b.x)
{
return(false);
}
// check y
if (line.a.y < line.b.y)
{
a = line.a;
b = line.b;
}
else
{
a = line.b;
b = line.a;
}
if (point.y < a.y || point.y > b.y)
{
return(false);
}
return(true);
}
private Collision GetCollision(Shape figure)
{
Circle circle = model.player;
Polygon poly = (Polygon)figure;
Vector[] dots = poly.dots.ToArray();
for (int i = 0; i < dots.Length - 1; i++)
{
Vector a = dots[i];
Vector b = dots[i + 1];
Line line = new Line(a, b);
if (Geom.IntersectCircleLineRectangles(circle, line))
{
float dist = Geom.Distance(line, circle.center);
if ((dist - circle.rad) <= PRECISION)
{
float prevDist = Geom.Distance(line, copyCircle.center);
if (dist < prevDist)
{
return(new Collision(line, Collision.Type.Normal));
}
}
}
else
{
float distCorner = Geom.DistanceCorner(circle, line);
if ((distCorner - circle.rad) <= PRECISION)
{
float prevDistCorner = Geom.DistanceCorner(copyCircle, line);
if (distCorner < prevDistCorner)
{
return(new Collision(line, Collision.Type.Corner));
}
}
}
}
return(null);
}