private static void GetPolygonLevel1GridIndex(List <GridIndex> result, GridSegment region, IList <GridPoint> gridPoints, IEnumerable <GridSegment> segments)
{
var beginX = Math.Floor(region.X1 / GridConfig.Level1XCellSpan) * GridConfig.Level1XCellSpan;
var beginY = Math.Floor(region.Y1 / GridConfig.Level1YCellSpan) * GridConfig.Level1YCellSpan;
var endX = Math.Floor(region.X2 / GridConfig.Level1XCellSpan) * GridConfig.Level1XCellSpan;
var endY = Math.Floor(region.Y2 / GridConfig.Level1YCellSpan) * GridConfig.Level1YCellSpan;
var row = (int)Math.Round((endY - beginY) / GridConfig.Level1YCellSpan) + 1;
var column = (int)Math.Round((endX - beginX) / GridConfig.Level1XCellSpan) + 1;
if (beginX == endX && beginY == endY)
{
// 只占用顶级一个格子
GetPolygonLevel2GridIndex(result, region, gridPoints, segments);
}
else
{
for (int i = 0; i < column; i++)
{
var x = beginX + i * GridConfig.Level1XCellSpan;
for (int j = 0; j < row; j++)
{
var y = beginY + j * GridConfig.Level1YCellSpan;
var gridRect = new GridRect(x, y, GridConfig.Level1XCellSpan, GridConfig.Level1YCellSpan);
if (gridPoints.Any(p => RelationPointAndRect(p, gridRect) == GridRelationShip.Within))
{
// 多边形顶点所在的格子
// 不能压到边界，否则会判断过界，所以边界需要退一点
// Intersect
GetPolygonLevel2GridIndex(result, new GridSegment(gridRect.Point1.X, gridRect.Point1.Y, gridRect.Point4.X - 0.5d * GridConfig.Level4XCellSpan, gridRect.Point4.Y - 0.5d * GridConfig.Level4YCellSpan), gridPoints, segments);
}
else
{
var relationship = RelationRectAndPanel(gridRect, segments);
if (relationship == GridRelationShip.Within)
{
// 多边形背部完全包含的顶级格子，无需再分
//Within
result.Add(new GridIndex()
{
Index1 = new GridPoint(x + 0.5d * GridConfig.Level1XCellSpan,
y + 0.5d * GridConfig.Level1YCellSpan)
.TranformGridIndex(
GridConfig.LEVEL1_X_GRID,
GridConfig.LEVEL1_Y_GRID,
GridConfig.Level1XCellSpan,
GridConfig.Level1YCellSpan)
});
}
else if (relationship == GridRelationShip.Intersect)
{
// 多边形与格子相交, 继续再分
// 不能压到边界，否则会判断过界，所以边界需要退一点
// Intersect
GetPolygonLevel2GridIndex(result, new GridSegment(gridRect.Point1.X, gridRect.Point1.Y, gridRect.Point4.X - 0.5d * GridConfig.Level4XCellSpan, gridRect.Point4.Y - 0.5d * GridConfig.Level4YCellSpan), gridPoints, segments);
}
}
}
}
}
}
private static double GetX(double y, GridSegment segment)
{
if (segment.X1 == segment.X2)
{
return(segment.X1);
}
return((y - segment.Y1) * (segment.X1 - segment.X2) / (segment.Y1 - segment.Y2) + segment.X1);
}
private static GridRelationShip RelationSegmentAndPanel(GridSegment segment, IEnumerable <GridSegment> segments)
{
if (segments.Any(s => RelationSegmentAndSegment(segment, s) == GridRelationShip.Intersect))
{
return(GridRelationShip.Intersect);
}
return(GridRelationShip.None);
}
private static GridRelationShip RelationSegmentAndSegment(GridSegment segment1, GridSegment segment2)
{
var vector1 = GetVector(segment1.Point1, segment2.Point1);
var vector2 = GetVector(segment1.Point2, segment2.Point1);
var vector3 = GetVector(segment2.Point2, segment2.Point1);
var vector4 = GetVector(segment2.Point1, segment1.Point1);
var vector5 = GetVector(segment2.Point2, segment1.Point1);
var vector6 = GetVector(segment1.Point2, segment1.Point1);
if (CrossMul(vector1, vector3) * CrossMul(vector2, vector3) <= 0 &&
CrossMul(vector4, vector6) * CrossMul(vector5, vector6) <= 0)
{
return(GridRelationShip.Intersect);
}
return(GridRelationShip.None);
}
private static void GetPolygonLevel4GridIndex(List <GridIndex> result, GridSegment region, IList <GridPoint> gridPoints, IEnumerable <GridSegment> segments)
{
var beginX = Math.Floor(region.X1 / GridConfig.Level4XCellSpan) * GridConfig.Level4XCellSpan;
var beginY = Math.Floor(region.Y1 / GridConfig.Level4YCellSpan) * GridConfig.Level4YCellSpan;
var endX = Math.Floor(region.X2 / GridConfig.Level4XCellSpan) * GridConfig.Level4XCellSpan;
var endY = Math.Floor(region.Y2 / GridConfig.Level4YCellSpan) * GridConfig.Level4YCellSpan;
var row = (int)Math.Round((endY - beginY) / GridConfig.Level4YCellSpan) + 1;
var column = (int)Math.Round((endX - beginX) / GridConfig.Level4XCellSpan) + 1;
if (beginX == endX && beginY == endY)
{
// 只占用四级一个格子，无需再分
var point = new GridPoint(beginX, beginY);
result.Add(GetPointGridIndex(point));
}
else
{
for (int i = 0; i < column; i++)
{
var x = beginX + i * GridConfig.Level4XCellSpan;
for (int j = 0; j < row; j++)
{
var y = beginY + j * GridConfig.Level4YCellSpan;
var gridRect = new GridRect(x, y, GridConfig.Level4XCellSpan, GridConfig.Level4YCellSpan);
var point = new GridPoint(x + 0.5d * GridConfig.Level4XCellSpan, y + 0.5d * GridConfig.Level4YCellSpan);
if (gridPoints.Any(p => RelationPointAndRect(p, gridRect) == GridRelationShip.Within))
{
result.Add(GetPointGridIndex(point));
}
else
{
var relationship = RelationRectAndPanel(gridRect, segments);
if (relationship != GridRelationShip.None)
{
if (relationship == GridRelationShip.Within)
{
}
result.Add(GetPointGridIndex(point));
}
}
}
}
}
}
private static void GetPolygonLevel1GridIndex(List<GridIndex> result, GridSegment region, IList<GridPoint> gridPoints, IEnumerable<GridSegment> segments)
{
var beginX = Math.Floor(region.X1 / GridConfig.Level1XCellSpan) * GridConfig.Level1XCellSpan;
var beginY = Math.Floor(region.Y1 / GridConfig.Level1YCellSpan) * GridConfig.Level1YCellSpan;
var endX = Math.Floor(region.X2 / GridConfig.Level1XCellSpan) * GridConfig.Level1XCellSpan;
var endY = Math.Floor(region.Y2 / GridConfig.Level1YCellSpan) * GridConfig.Level1YCellSpan;
var row = (int)Math.Round((endY - beginY) / GridConfig.Level1YCellSpan) + 1;
var column = (int)Math.Round((endX - beginX) / GridConfig.Level1XCellSpan) + 1;
if (beginX == endX && beginY == endY)
{
// 只占用顶级一个格子
GetPolygonLevel2GridIndex(result, region, gridPoints, segments);
}
else
{
for (int i = 0; i < column; i++)
{
var x = beginX + i * GridConfig.Level1XCellSpan;
for (int j = 0; j < row; j++)
{
var y = beginY + j * GridConfig.Level1YCellSpan;
var gridRect = new GridRect(x, y, GridConfig.Level1XCellSpan, GridConfig.Level1YCellSpan);
if (gridPoints.Any(p => RelationPointAndRect(p, gridRect) == GridRelationShip.Within))
{
// 多边形顶点所在的格子
// 不能压到边界，否则会判断过界，所以边界需要退一点
// Intersect
GetPolygonLevel2GridIndex(result, new GridSegment(gridRect.Point1.X, gridRect.Point1.Y, gridRect.Point4.X - 0.5d * GridConfig.Level4XCellSpan, gridRect.Point4.Y - 0.5d * GridConfig.Level4YCellSpan), gridPoints, segments);
}
else
{
var relationship = RelationRectAndPanel(gridRect, segments);
if (relationship == GridRelationShip.Within)
{
// 多边形背部完全包含的顶级格子，无需再分
//Within
result.Add(new GridIndex()
{
Index1 = new GridPoint(x + 0.5d * GridConfig.Level1XCellSpan,
y + 0.5d * GridConfig.Level1YCellSpan)
.TranformGridIndex(
GridConfig.LEVEL1_X_GRID,
GridConfig.LEVEL1_Y_GRID,
GridConfig.Level1XCellSpan,
GridConfig.Level1YCellSpan)
});
}
else if (relationship == GridRelationShip.Intersect)
{
// 多边形与格子相交, 继续再分
// 不能压到边界，否则会判断过界，所以边界需要退一点
// Intersect
GetPolygonLevel2GridIndex(result, new GridSegment(gridRect.Point1.X, gridRect.Point1.Y, gridRect.Point4.X - 0.5d * GridConfig.Level4XCellSpan, gridRect.Point4.Y - 0.5d * GridConfig.Level4YCellSpan), gridPoints, segments);
}
}
}
}
}
}
private static GridRelationShip RelationSegmentAndSegment(GridSegment segment1, GridSegment segment2)
{
var vector1 = GetVector(segment1.Point1, segment2.Point1);
var vector2 = GetVector(segment1.Point2, segment2.Point1);
var vector3 = GetVector(segment2.Point2, segment2.Point1);
var vector4 = GetVector(segment2.Point1, segment1.Point1);
var vector5 = GetVector(segment2.Point2, segment1.Point1);
var vector6 = GetVector(segment1.Point2, segment1.Point1);
if(CrossMul(vector1, vector3) * CrossMul(vector2, vector3) <=0
&& CrossMul(vector4, vector6) * CrossMul(vector5, vector6) <=0)
{
return GridRelationShip.Intersect;
}
return GridRelationShip.None;
}
private static GridRelationShip RelationSegmentAndPanel(GridSegment segment, IEnumerable<GridSegment> segments)
{
if(segments.Any(s => RelationSegmentAndSegment(segment, s) == GridRelationShip.Intersect))
{
return GridRelationShip.Intersect;
}
return GridRelationShip.None;
}
private static double GetX(double y, GridSegment segment)
{
if (segment.X1 == segment.X2)
{
return segment.X1;
}
return (y - segment.Y1) * (segment.X1 - segment.X2) / (segment.Y1 - segment.Y2) + segment.X1;
}
private static void GetPolygonLevel4GridIndex(List<GridIndex> result, GridSegment region, IList<GridPoint> gridPoints, IEnumerable<GridSegment> segments)
{
var beginX = Math.Floor(region.X1 / GridConfig.Level4XCellSpan) * GridConfig.Level4XCellSpan;
var beginY = Math.Floor(region.Y1 / GridConfig.Level4YCellSpan) * GridConfig.Level4YCellSpan;
var endX = Math.Floor(region.X2 / GridConfig.Level4XCellSpan) * GridConfig.Level4XCellSpan;
var endY = Math.Floor(region.Y2 / GridConfig.Level4YCellSpan) * GridConfig.Level4YCellSpan;
var row = (int)Math.Round((endY - beginY) / GridConfig.Level4YCellSpan) + 1;
var column = (int)Math.Round((endX - beginX) / GridConfig.Level4XCellSpan) + 1;
if (beginX == endX && beginY == endY)
{
// 只占用四级一个格子，无需再分
var point = new GridPoint(beginX, beginY);
result.Add(GetPointGridIndex(point));
}
else
{
for (int i = 0; i < column; i++)
{
var x = beginX + i * GridConfig.Level4XCellSpan;
for (int j = 0; j < row; j++)
{
var y = beginY + j * GridConfig.Level4YCellSpan;
var gridRect = new GridRect(x, y, GridConfig.Level4XCellSpan, GridConfig.Level4YCellSpan);
var point = new GridPoint(x + 0.5d * GridConfig.Level4XCellSpan, y + 0.5d * GridConfig.Level4YCellSpan);
if (gridPoints.Any(p => RelationPointAndRect(p, gridRect) == GridRelationShip.Within))
{
result.Add(GetPointGridIndex(point));
}
else
{
var relationship = RelationRectAndPanel(gridRect, segments);
if (relationship != GridRelationShip.None)
{
if (relationship == GridRelationShip.Within)
{
}
result.Add(GetPointGridIndex(point));
}
}
}
}
}
}