public static float GetDistanceWithParallelogram(Vector3 anchorPoint, Vector3 baseVertex, Vector3 edge1, Vector3 edge2, out Vector3 location)
{
// 平行四辺形のある平面の法線
Vector3 normOnParallelogram = Vector3.Normalize(Vector3.Cross(edge1, edge2));
// baseVertexへ
Vector3 toBaseVertex = baseVertex - anchorPoint;
// anchorPointから平行四辺形のある平面への最短ベクトル(垂線)
Vector3 perpendicular = normOnParallelogram * Vector3.Dot(toBaseVertex, normOnParallelogram);
// 垂線の足
Vector3 foot = anchorPoint + perpendicular;
// 垂線の足が平行四辺形の中かどうか
if (GeometryCalc.PointOverParallelogram(foot, baseVertex, edge1, edge2))
{
location = foot;
return(perpendicular.Length());
}
Vector3 oppositeVertex = baseVertex + edge1 + edge2;
Vector3 location1, location2, location3, location4;
float distance1 = GeometryCalc.GetDistanceWithLine(anchorPoint, baseVertex, baseVertex + edge1, out location1);
float distance2 = GeometryCalc.GetDistanceWithLine(anchorPoint, baseVertex, baseVertex + edge2, out location2);
float distance3 = GeometryCalc.GetDistanceWithLine(anchorPoint, oppositeVertex, oppositeVertex - edge1, out location3);
float distance4 = GeometryCalc.GetDistanceWithLine(anchorPoint, oppositeVertex, oppositeVertex - edge2, out location4);
float minDistance = new float[] { distance1, distance2, distance3, distance4 }.Min();
if (minDistance == distance1)
{
location = location1;
}
else if (minDistance == distance2)
{
location = location2;
}
else if (minDistance == distance3)
{
location = location3;
}
else
{
location = location4;
}
return(minDistance);
}
/// <summary>
/// 点と三角形ポリゴンとの最短距離を返します
/// </summary>
/// <param name="anchorPoint">基準点</param>
/// <param name="vertex1">三角形の頂点</param>
/// <param name="vertex2">三角形の頂点</param>
/// <param name="vertex3">三角形の頂点</param>
/// <param name="location">基準点に対して最も近い三角形上の点</param>
/// <returns></returns>
public static float GetDistanceWithTriangle(Vector3 anchorPoint, Vector3 vertex1, Vector3 vertex2, Vector3 vertex3, out Vector3 location)
{
Vector3 edge2 = vertex2 - vertex1;
Vector3 edge3 = vertex3 - vertex1;
Vector3 triangleVert = Vector3.Normalize(Vector3.Cross(edge2, edge3));
Vector3 toAnchor = anchorPoint - vertex1;
float vertDistance = Vector3.Dot(triangleVert, toAnchor);
Vector3 testDir = -triangleVert * vertDistance * 2;
Motion.Old.MotionDataLine vertLine = new Motion.Old.MotionDataLine(anchorPoint, testDir);
float distance;
if (GeometryCalc.GetCollisionTriangle(vertLine.End, vertLine.AnotherEnd, vertex1, vertex2, vertex3, out distance))
{
location = anchorPoint + Vector3.Normalize(testDir) * distance;
return(distance);
}
Vector3 location1, location2, location3;
float distance1 = GeometryCalc.GetDistanceWithLine(anchorPoint, vertex1, vertex2, out location1);
float distance2 = GeometryCalc.GetDistanceWithLine(anchorPoint, vertex2, vertex3, out location2);
float distance3 = GeometryCalc.GetDistanceWithLine(anchorPoint, vertex3, vertex1, out location3);
if (distance1 < distance2 && distance1 < distance3)
{
location = location1;
return(distance1);
}
else if (distance2 < distance1 && distance2 < distance3)
{
location = location2;
return(distance2);
}
else
{
location = location3;
return(distance3);
}
}
public static bool GetCollisionParallelogram(Vector3 lineSource, Vector3 lineDestination, Vector3 baseVertex, Vector3 edge1, Vector3 edge2, out float distance)
{
distance = float.MaxValue;
Vector3 lineEdge = lineDestination - lineSource;
// 平行四辺形のある平面の法線
Vector3 normOnParallelogram = Vector3.Normalize(Vector3.Cross(edge1, edge2));
// baseVertexへ
Vector3 toBaseVertex = baseVertex - lineSource;
// 平面の法線成分
float toBaseVertexDistance = Vector3.Dot(normOnParallelogram, toBaseVertex);
float lineEdgeDistance = Vector3.Dot(normOnParallelogram, lineEdge);
if (lineEdgeDistance == 0)
{
// 引数の線分と平行四辺形が平行な時
return(false);
}
float ratio = toBaseVertexDistance / lineEdgeDistance;
if (ratio < 0 && 1 < ratio)
{
// 向きが逆であるか，長さが足りない
return(false);
}
// 引数の線分と平行四辺形のある平面との交点へのベクトル
Vector3 lineEdgeToParallelogram = lineEdge * ratio;
// 引数の線分と平行四辺形のある平面との交点
Vector3 onPlane = lineSource + lineEdgeToParallelogram;
if (GeometryCalc.PointOverParallelogram(onPlane, baseVertex, edge1, edge2))
{
distance = lineEdgeToParallelogram.Length();
return(true);
}
return(false);
}
