private static TilePair EnclosingTile(PixelPair pixel)
{
int tilex, tiley;
TileSystem.PixelXYToTileXY(pixel.X, pixel.Y, out tilex, out tiley);
return new TilePair(tilex, tiley);
}
private static void ScaleTile(TilePair nw, TilePair se, int lod, int targetlod, out PixelPair pixnw, out PixelPair pixse)
{
se.X++;
se.Y++;
var diff = targetlod - lod;
var factor = Math.Pow(2.0, diff);
var targetnw = new TilePair((int)(nw.X * factor), (int)(nw.Y * factor));
var targetse = new TilePair((int)(se.X * factor), (int)(se.Y * factor));
if (targetnw.X == targetse.X) targetse.X++;
if (targetnw.Y == targetse.Y) targetse.Y++;
if (diff < 0) {
if (targetse.X * (1.0 / factor) < se.X) targetse.X++;
if (targetse.Y * (1.0 / factor) < se.Y) targetse.Y++;
}
pixnw = Pixel(targetnw);
pixse = Pixel(targetse);
}
public Point? GetScreenPosition(PixelPair pixel)
{
if (!this.IsScreenPositionInferred()) return null;
return new Point(pixel.X - this.PixelNW.X, pixel.Y - this.PixelNW.Y);
}
public TilePair GetEnclosingTile(PixelPair pixel)
{
return EnclosingTile(pixel);
}
public Point? GetClippedScreenPosition(PixelPair pixel)
{
if (!this.IsScreenPositionInferred()) return null;
int x;
if (this.PixelNW.X > pixel.X)
x = 0;
else if (pixel.X > this.PixelSE.X)
x = this.PixelSE.X - this.PixelNW.X;
else
x = pixel.X - this.PixelNW.X;
int y;
if (this.PixelNW.Y > pixel.Y)
y = 0;
else if (pixel.Y > this.PixelSE.Y)
y = this.PixelSE.Y - this.PixelNW.Y;
else
y = pixel.Y - this.PixelNW.Y;
return new Point(x, y);
}
public static IEnumerable<TilePair> IterateTiles(PixelPair nw, PixelPair se, int lod)
{
var mapwidth = TileSystem.MapSize(lod);
var boundx = se.X;
if (nw.X > boundx)
boundx += (int)mapwidth;
for (int x = nw.X; x < boundx; x += TILESIZE) {
for (int y = nw.Y; y < se.Y; y += TILESIZE) {
var actualx = x % (int)mapwidth;
yield return EnclosingTile(new PixelPair(actualx, y));
}
}
}
public static int CountTiles(PixelPair nw, PixelPair se, int lod)
{
var mapwidth = TileSystem.MapSize(lod);
var boundx = se.X;
if (nw.X > boundx)
boundx += (int)mapwidth;
int countx = (boundx - nw.X + TILESIZE - 1) / TILESIZE;
int county = (se.Y - nw.Y + TILESIZE - 1) / TILESIZE;
return countx * county;
}
