public IEnumerable <HeightmapTile> GetVisibleTiles()
{
// calculate visible rect between -1 and 1
float size = 1.0f / Mathf.Pow(2, Mathf.CeilToInt(zoomLevel));
Rect visibleArea = new Rect(-center.x, -center.y, size, size);
// Calculate all visible tiles from the visible area:
Vector2 resolution = new Vector2(settings.GetResolvedWidth(graph), settings.GetResolvedHeight(graph));
float scaledResolution = Mathf.Lerp(256, 128, 1 - (Mathf.CeilToInt(zoomLevel) - zoomLevel));
Vector2Int tileCount = new Vector2Int(Mathf.CeilToInt(resolution.x / scaledResolution), Mathf.CeilToInt(resolution.y / scaledResolution));
Vector2 offset = visibleArea.position - Vector2.one * (1 / Mathf.Pow(2, zoomLevel));
// Iterate over possibly visible tiles
var minTile = LocalToWorld(new Rect(offset.x, offset.y, size, size));
for (int x = 0; x < tileCount.x; x++)
{
for (int y = 0; y < tileCount.y; y++)
{
var tile = new HeightmapTile {
x = minTile.x + x, y = minTile.y + y, zoom = minTile.zoom
};
if (IsOutOfBounds(tile))
{
continue;
}
yield return(tile);
}
}
}
public Rect WorldToLocal(HeightmapTile worldPos)
{
float size = 1 / Mathf.Pow(2, worldPos.zoom);
int tileMax = (int)Mathf.Pow(2, worldPos.zoom);
float x = worldPos.x / (float)tileMax * 2.0f - 1.0f;
float y = worldPos.y / (float)tileMax * 2.0f - 1.0f;
return(new Rect(x, y, size, size));
}
public bool IsOutOfBounds(HeightmapTile tile)
{
// x is the zoom
if (tile.zoom < 0 || tile.zoom > 15)
{
return(true);
}
if (tile.x < 0 || tile.y < 0)
{
return(true);
}
int max = (int)Mathf.Pow(2, tile.zoom);
if (tile.x >= max || tile.y >= max)
{
return(true);
}
return(false);
}
