// returns first intersection point with box boundary or null if there are none
public static Vector2?MeetingPoint(this Ray2 ray, Box2 box)
{
var meetingDistance = double.PositiveInfinity;
for (Vector2.Axis axis = 0; axis < Vector2.Axis.Count; axis++)
{
var otherAxis = 1 - axis;
for (Interval.EndType end = 0; end < Interval.EndType.Count; end++)
{
var intersectionDistance = (box.Corner(end)[axis] - ray.Origin[axis]) / ray.Direction[axis];
if (intersectionDistance > 0)
{
var intersectionCoord = ray.Origin[otherAxis] + ray.Direction[otherAxis] * intersectionDistance;
if (box.Range(otherAxis).Contains(intersectionCoord))
{
meetingDistance = Math.Min(meetingDistance, intersectionDistance);
}
}
}
}
if (double.IsPositiveInfinity(meetingDistance))
{
return(null);
}
return(ray.PointAt(meetingDistance));
}
private void FindSplitAxis(KDNode node)
{
// 比较快的方法 选择范围大的维度
Vector2 range = node.max - node.min;
Vector2.Axis splitAxis = Vector2.Axis.X;
if (range.y > range.x)
{
splitAxis = Vector2.Axis.Y;
}
node.splitAxis = splitAxis;
}
public static Interval Range(this Box2 @this, Vector2.Axis axis)
{
switch (axis)
{
case Vector2.Axis.X:
return(@this.XRange);
case Vector2.Axis.Y:
return(@this.YRange);
default:
throw new ArgumentOutOfRangeException("Invalid 2D axis " + axis.ToString());
}
}
// Adds a specific corridor (defined by the input parameters) to `_data`. It also adds all
// secondary rooms intersecting the corridor path.
private void AddCorridor(int start, int end, int constant, Vector2.Axis axis)
{
var t = Math.Min(start, end);
while (t <= Math.Max(start, end))
{
var point = Vector2.Zero;
if (axis == Vector2.Axis.X)
{
point = new Vector2(t, constant);
}
else if (axis == Vector2.Axis.Y)
{
point = new Vector2(constant, t);
}
t++;
foreach (Room room in Rooms.GetChildren())
{
if (IsMainRoom(room))
{
continue;
}
var topLeft = Level.WorldToMap(room.Position - room.Size / 2);
var bottomright = Level.WorldToMap(room.Position + room.Size / 2);
if (topLeft.x <= point.x &&
point.x < bottomright.x &&
topLeft.y <= point.y &&
point.y < bottomright.y)
{
AddRoom(room);
t = axis == Vector2.Axis.X ? (int)bottomright.x : (int)bottomright.y;
}
_data[point] = null;
}
}
}
private int FindSplitIndex(KDNode node, int retryOffset = 0)
{
// 取第一个 并将其后移 最终保证 左边都比它小 右边都比它大 有点类似于快速排序第一步
int start = node.startIndex + retryOffset;
int end = node.endIndex - 1;
Vector2.Axis splitAxis = node.splitAxis;
int pivot = permutation[start];
while (start < end)
{
while (start < end && managed[permutation[end]].position[splitAxis] >= managed[pivot].position[splitAxis])
{
--end;
}
permutation[start] = permutation[end];
while (start < end && managed[permutation[start]].position[splitAxis] <= managed[pivot].position[splitAxis])
{
++start;
}
permutation[end] = permutation[start];
}
permutation[start] = pivot;
int foundIndex = start;
if (foundIndex == node.startIndex || foundIndex == node.endIndex)
{
// 运气不太好 出现了极限情况
if (node.startIndex + retryOffset < node.endIndex - 1)
{
// Debug.LogError($"再试一次 start={node.startIndex} off={retryOffset} end={node.endIndex}");
foundIndex = FindSplitIndex(node, retryOffset + 1);
return(foundIndex);
}
}
node.splitPos = managed[permutation[foundIndex]].position[splitAxis];
return(foundIndex);
}
private void AddCorridor(Dictionary <Vector2, object> dataDict, float start, float end, float constant, Vector2.Axis axis)
{
var minVal = (int)Math.Min(start, end);
var maxVal = (int)Math.Max(start, end);
for (int t = minVal; t <= maxVal; t++)
{
var point = Vector2.Zero;
if (axis == Vector2.Axis.X)
{
point = new Vector2(t, constant);
}
else
{
point = new Vector2(constant, t);
}
dataDict[point] = null;
}
}
/// <summary>The <c>_addCorridor</c> method adds corridor points along either the X axis or the Y axis
/// starting from the <c>start</c> position to the <c>end</c> position.</summary>
public void _addCorridor(Dictionary <Vector2, int> data, int start, int end, int constant, Vector2.Axis axis)
{
for (int t = Math.Min(start, end); t <= Math.Max(start, end); t++)
{
var point = Vector2.Zero;
switch (axis)
{
case Vector2.Axis.X:
point = new Vector2(t, constant);
break;
case Vector2.Axis.Y:
point = new Vector2(constant, t);
break;
}
data[point] = 0;
}
}
