@Override
public 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; i < numVers; i++) {
Vector2f ver = vers[i];
Vector2f nextVer = vers[(i + 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) Math.sqrt(edgeX * edgeX + edgeY * edgeY);
float distanceToEdge = Math.abs(a.x * edgeY - a.y * edgeX) / edgeLen;
if (distanceToEdge <= c1.rad) {
distanceToEdge -= c1.rad;
if (distance > distanceToEdge || distance == -1F) {
edgeNumber = i;
distance = distanceToEdge;
normal.set(edgeNormal.x, edgeNormal.y);
}
}
}
}
if (edgeNumber > -1) {
PContact c = new PContact();
c.overlap = distance;
c.normal = normal;
c.pos = c1._pos.sub(normal.mul(c1.rad));
cs[0] = c;
return 1;
}
boolean hit = true;
for (int i = 0; i < numVers; i++) {
Vector2f ver = vers[i];
Vector2f nextVer = vers[(i + 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;
}
