/**
* Ray-cast the world for all fixtures in the path of the ray. Your callback controls whether you
* get the closest point, any point, or n-points. The ray-cast ignores shapes that contain the
* starting point.
*
* @param callback a user implemented callback class.
* @param point1 the ray starting point
* @param point2 the ray ending point
*/
public void raycast(RayCastCallback callback, Vec2 point1, Vec2 point2) {
wrcwrapper.broadPhase = m_contactManager.m_broadPhase;
wrcwrapper.callback = callback;
input.maxFraction = 1.0f;
input.p1.set(point1);
input.p2.set(point2);
m_contactManager.m_broadPhase.raycast(wrcwrapper, input);
}
@Override
public void raycast(
org.jbox2d.callbacks.TreeRayCastCallback callback, org.jbox2d.collision.RayCastInput input) {
final Vec2 p1 = input.p1;
final Vec2 p2 = input.p2;
float p1x = p1.x, p2x = p2.x, p1y = p1.y, p2y = p2.y;
float vx, vy;
float rx, ry;
float absVx, absVy;
float cx, cy;
float hx, hy;
float tempx, tempy;
r.x = p2x - p1x;
r.y = p2y - p1y;
assert ((r.x * r.x + r.y * r.y) > 0f);
r.normalize();
rx = r.x;
ry = r.y;
// v is perpendicular to the segment.
vx = -1f * ry;
vy = 1f * rx;
absVx = org.jbox2d.common.MathUtils.abs(vx);
absVy = org.jbox2d.common.MathUtils.abs(vy);
// Separating axis for segment (Gino, p80).
// |dot(v, p1 - c)| > dot(|v|, h)
float maxFraction = input.maxFraction;
// Build a bounding box for the segment.
final org.jbox2d.collision.AABB segAABB = aabb;
// Vec2 t = p1 + maxFraction * (p2 - p1);
// before inline
// temp.set(p2).subLocal(p1).mulLocal(maxFraction).addLocal(p1);
// Vec2.minToOut(p1, temp, segAABB.lowerBound);
// Vec2.maxToOut(p1, temp, segAABB.upperBound);
tempx = (p2x - p1x) * maxFraction + p1x;
tempy = (p2y - p1y) * maxFraction + p1y;
segAABB.lowerBound.x = p1x < tempx ? p1x : tempx;
segAABB.lowerBound.y = p1y < tempy ? p1y : tempy;
segAABB.upperBound.x = p1x > tempx ? p1x : tempx;
segAABB.upperBound.y = p1y > tempy ? p1y : tempy;
// end inline
nodeStackIndex = 0;
nodeStack[nodeStackIndex++] = m_root;
while (nodeStackIndex > 0) {
final DynamicTreeNode node = nodeStack[--nodeStackIndex];
if (node == null) {
continue;
}
final org.jbox2d.collision.AABB nodeAABB = node.aabb;
if (!org.jbox2d.collision.AABB.testOverlap(nodeAABB, segAABB)) {
continue;
}
// Separating axis for segment (Gino, p80).
// |dot(v, p1 - c)| > dot(|v|, h)
// node.aabb.getCenterToOut(c);
// node.aabb.getExtentsToOut(h);
cx = (nodeAABB.lowerBound.x + nodeAABB.upperBound.x) * .5f;
cy = (nodeAABB.lowerBound.y + nodeAABB.upperBound.y) * .5f;
hx = (nodeAABB.upperBound.x - nodeAABB.lowerBound.x) * .5f;
hy = (nodeAABB.upperBound.y - nodeAABB.lowerBound.y) * .5f;
tempx = p1x - cx;
tempy = p1y - cy;
float separation =
org.jbox2d.common.MathUtils.abs(vx * tempx + vy * tempy) - (absVx * hx + absVy * hy);
if (separation > 0.0f) {
continue;
}
if (node.child1 == null) {
subInput.p1.x = p1x;
subInput.p1.y = p1y;
subInput.p2.x = p2x;
subInput.p2.y = p2y;
subInput.maxFraction = maxFraction;
float value = callback.raycastCallback(subInput, node.id);
if (value == 0.0f) {
// The client has terminated the ray cast.
return;
}
if (value > 0.0f) {
// Update segment bounding box.
maxFraction = value;
// temp.set(p2).subLocal(p1).mulLocal(maxFraction).addLocal(p1);
// Vec2.minToOut(p1, temp, segAABB.lowerBound);
// Vec2.maxToOut(p1, temp, segAABB.upperBound);
tempx = (p2x - p1x) * maxFraction + p1x;
tempy = (p2y - p1y) * maxFraction + p1y;
segAABB.lowerBound.x = p1x < tempx ? p1x : tempx;
segAABB.lowerBound.y = p1y < tempy ? p1y : tempy;
segAABB.upperBound.x = p1x > tempx ? p1x : tempx;
segAABB.upperBound.y = p1y > tempy ? p1y : tempy;
}
} else {
if (nodeStack.length - nodeStackIndex - 2 <= 0) {
DynamicTreeNode[] newBuffer = new DynamicTreeNode[nodeStack.length * 2];
System.arraycopy(nodeStack, 0, newBuffer, 0, nodeStack.length);
nodeStack = newBuffer;
}
nodeStack[nodeStackIndex++] = node.child1;
nodeStack[nodeStackIndex++] = node.child2;
}
}
}
