public IEnumerable <Rect> SweepDirtyRect(GStylizedTerrain terrain)
{
if (terrain.TerrainData == null)
{
return(new List <Rect>());
}
int gridSize = terrain.TerrainData.Geometry.ChunkGridSize;
List <Rect> uvRects = new List <Rect>();
for (int x = 0; x < gridSize; ++x)
{
for (int z = 0; z < gridSize; ++z)
{
uvRects.Add(GCommon.GetUvRange(gridSize, x, z));
}
}
HashSet <Rect> dirtyRects = new HashSet <Rect>();
Vector3 terrainSize = new Vector3(
terrain.TerrainData.Geometry.Width,
terrain.TerrainData.Geometry.Height,
terrain.TerrainData.Geometry.Length);
float splineSize = Mathf.Max(1, Width + FalloffWidth * 2);
Vector2 sweepRectSize = new Vector2(
Mathf.InverseLerp(0, terrainSize.x, splineSize),
Mathf.InverseLerp(0, terrainSize.z, splineSize));
Rect sweepRect = new Rect();
sweepRect.size = sweepRectSize;
int segmentCount = Spline.Segments.Count;
for (int sIndex = 0; sIndex < segmentCount; ++sIndex)
{
float tStep = 1f / (Smoothness - 1);
for (int tIndex = 0; tIndex < Smoothness - 1; ++tIndex)
{
float t = tIndex * tStep;
Vector3 worldPos = transform.TransformPoint(Spline.EvaluatePosition(sIndex, t));
Vector3 scale = transform.TransformVector(Spline.EvaluateScale(sIndex, t));
float maxScaleComponent = Mathf.Max(Mathf.Abs(scale.x), Mathf.Abs(scale.y), Mathf.Abs(scale.z));
Vector3 normalizedPos = terrain.WorldPointToNormalized(worldPos);
sweepRect.center = new Vector2(normalizedPos.x, normalizedPos.z);
sweepRect.size = sweepRectSize * maxScaleComponent;
for (int rIndex = 0; rIndex < uvRects.Count; ++rIndex)
{
if (uvRects[rIndex].Overlaps(sweepRect))
{
dirtyRects.Add(uvRects[rIndex]);
}
}
}
}
return(dirtyRects);
}
