public bool Intersects(Line other)
{
Vector2f lineSegmentStart = new Vector2f(other.GetX1(), other.GetY1());
Vector2f lineSegmentEnd = new Vector2f(other.GetX2(), other.GetY2());
Vector2f circleCenter = new Vector2f(GetCenterX(), GetCenterY());
Vector2f closest;
Vector2f segv = lineSegmentEnd.Sub(lineSegmentStart);
Vector2f ptv = circleCenter.Sub(lineSegmentStart);
float segvLength = segv.Len();
float projvl = ptv.Dot(segv) / segvLength;
if (projvl < 0)
{
closest = lineSegmentStart;
}
else if (projvl > segvLength)
{
closest = lineSegmentEnd;
}
else
{
Vector2f projv = segv.Mul(projvl / segvLength);
closest = lineSegmentStart.Add(projv);
}
bool intersects = circleCenter.Sub(closest).LengthSquared() <= GetRadius()
* GetRadius();
return(intersects);
}
public static Vector2f Mult(Vector2f vector, float scalar)
{
Vector2f answer = new Vector2f(vector);
return(answer.Mul(scalar));
}
public virtual int Collide(PShape s1, PShape s2, PContact[] cs) {
if (s1._type != PShapeType.CIRCLE_SHAPE
|| s2._type != PShapeType.CONVEX_SHAPE
&& s2._type != PShapeType.BOX_SHAPE) {
return 0;
}
PCircleShape c1 = (PCircleShape) s1;
PConvexPolygonShape p1 = (PConvexPolygonShape) s2;
float distance = -1F;
int edgeNumber = -1;
Vector2f[] vers = p1.vers;
int numVers = p1.numVertices;
Vector2f normal = new Vector2f();
Vector2f edgeNormal = new Vector2f();
Vector2f a = new Vector2f();
Vector2f b = new Vector2f();
int num = 0;
for (int i = 0; i < numVers; i++) {
a.Set(c1._pos.x - vers[i].x, c1._pos.y - vers[i].y);
distance = a.Length();
distance -= c1.rad;
if (distance <= 0.0F) {
PContact c = new PContact();
c.overlap = distance;
a.Normalize();
c.normal.Set(a.x, a.y);
c.pos.Set(vers[i].x, vers[i].y);
cs[num] = c;
if (++num == 2) {
return num;
}
}
}
if (num > 0) {
return num;
}
for (int i_0 = 0; i_0 < numVers; i_0++) {
Vector2f ver = vers[i_0];
Vector2f nextVer = vers[(i_0 + 1) % numVers];
float edgeX = nextVer.x - ver.x;
float edgeY = nextVer.y - ver.y;
edgeNormal.Set(edgeY, -edgeX);
edgeNormal.Normalize();
a.Set(c1._pos.x - ver.x, c1._pos.y - ver.y);
b.Set(c1._pos.x - nextVer.x, c1._pos.y - nextVer.y);
if ((a.x * edgeX + a.y * edgeY) * (b.x * edgeX + b.y * edgeY) <= 0.0F) {
float edgeLen = (float) System.Math.Sqrt(edgeX * edgeX + edgeY * edgeY);
float distanceToEdge = System.Math.Abs(a.x * edgeY - a.y * edgeX)
/ edgeLen;
if (distanceToEdge <= c1.rad) {
distanceToEdge -= c1.rad;
if (distance > distanceToEdge || distance == -1F) {
edgeNumber = i_0;
distance = distanceToEdge;
normal.Set(edgeNormal.x, edgeNormal.y);
}
}
}
}
if (edgeNumber > -1) {
PContact c_1 = new PContact();
c_1.overlap = distance;
c_1.normal = normal;
c_1.pos = c1._pos.Sub(normal.Mul(c1.rad));
cs[0] = c_1;
return 1;
}
bool hit = true;
for (int i_2 = 0; i_2 < numVers; i_2++) {
Vector2f ver = vers[i_2];
Vector2f nextVer = vers[(i_2 + 1) % numVers];
float v1x = nextVer.x - ver.x;
float v1y = nextVer.y - ver.y;
float v2x = c1._pos.x - ver.x;
float v2y = c1._pos.y - ver.y;
if (v1x * v2y - v1y * v2x >= 0.0F) {
continue;
}
hit = false;
break;
}
if (hit) {
distance = 1.0F;
normal = new Vector2f();
for (int i = 0; i < numVers; i++) {
Vector2f ver = vers[i];
Vector2f nextVer = vers[(i + 1) % numVers];
a.Set(nextVer.x - ver.x, nextVer.y - ver.y);
a.Normalize();
float d = c1._pos.Sub(ver).Cross(a);
if (d < 0.0F && (distance == 1.0F || distance < d)) {
distance = d;
normal.Set(a.y, -a.x);
}
}
if (distance != 1.0F) {
PContact c = new PContact();
c.normal.Set(normal.x, normal.y);
c.pos.Set(c1._pos.x, c1._pos.y);
c.overlap = distance;
cs[0] = c;
return 1;
}
}
return 0;
}
public static Vector2f Mult(Vector2f vector, float scalar) {
Vector2f answer = new Vector2f(vector);
return answer.Mul(scalar);
}