// Cast a line from A to B, checking for collisions with other entities.
public IEnumerable <LineCastResult> LineCastAll(DVector3 start, DVector3 end, int ignoreTeam = -1)
{
var start2d = new DVector2(start.x, start.z);
var end2d = new DVector2(end.x, end.z);
foreach (Collider c in colliders)
{
if (c.entity.team == ignoreTeam)
{
continue;
}
var position2d = new DVector2(c.entity.position.x, c.entity.position.z);
DVector2 result;
// FIXME: Need to adjust positions to correct for wrap.
// FIXME: Some cases still not handled properly.
//
// _______________
// | / |
// ---X-----------
// /
// /
// O
// /
// /
// Circle intersects at O, which is a miss, but a real intersect happens at X.
if (Utility.IntersectLineCircle(position2d, c.radius, start2d, end2d, out result))
{
// Possible hit, work out the correct 3D position at the intersect.
var result3d = new DVector3(result.x, start.y, result.y);
var a = result3d - start;
var bhat = (end - start).normalized;
var ab = DVector3.Dot(a, bhat);
var intersectPoint = start + bhat * ab;
var height = intersectPoint.y;
var bottom = c.entity.position.y;
var top = bottom + c.height;
Logger.Log("result3d: {0} a: {1} bhat: {2} ab: {3} height: {4} bottom: {5} top:{6}",
result3d, a, bhat, ab, height, bottom, top);
DebugExtension.DebugPoint((UnityEngine.Vector3)intersectPoint, UnityEngine.Color.blue, 10, 10);
UnityEngine.Debug.DrawLine((UnityEngine.Vector3)start, (UnityEngine.Vector3)end, UnityEngine.Color.green, 10);
UnityEngine.Debug.DrawLine((UnityEngine.Vector3)start, (UnityEngine.Vector3)result3d, UnityEngine.Color.green, 10);
if (bottom <= height && height <= top)
{
var r = new LineCastResult();
r.entity = c.entity;
r.position = intersectPoint;
yield return(r);
}
}
}
}
// Directly examine the map to determine if a tile is passible.
bool MapPassable(int x, int z)
{
for (int xoff = 0; xoff < granularity; xoff += 1)
{
for (int zoff = 0; zoff < granularity; zoff += 1)
{
var pos = new DVector3(x + xoff + DReal.Half, 0, z + zoff + DReal.Half);
var normal = map.Normal(pos);
var up = new DVector3(0, 1, 0);
var slope = DVector3.Dot(normal, up);
if (slope < slopeLimit)
{
// Too sloped.
return(false);
}
if (map.Height(pos) < 0)
{
// Underwater.
return(false);
}
}
}
return(true);
}
