City-Lifeline-Cockpit/.scratch/gis-investigation-subagent/tile-mosaic.ps1

param(
  [int]$Zoom = 15,
  [double[]]$Bounds = @(110.328749941417, 28.3917230659234, 110.465779226663, 28.4913038992907),
  [int]$MaxWidth = 6500,
  [string]$Output = 'E:\City-Lifeline-Cockpit-TvT\.scratch\gis-investigation-subagent\city-z15.jpg'
)
$ErrorActionPreference = 'Stop'
Add-Type -AssemblyName System.Drawing
$n = [math]::Pow(2, $Zoom)
function TileX([double]$lon) { return [int][math]::Floor(($lon + 180) / 360 * $n) }
function GoogleY([double]$lat) {
  $rad = $lat * [math]::PI / 180
  return [int][math]::Floor((1 - [math]::Log([math]::Tan($rad) + 1 / [math]::Cos($rad)) / [math]::PI) / 2 * $n)
}
$x0 = TileX $Bounds[0]; $x1 = TileX $Bounds[2]
$y0 = GoogleY $Bounds[3]; $y1 = GoogleY $Bounds[1]
$scale = [math]::Min(1.0, [double]$MaxWidth / (($x1 - $x0 + 1) * 256.0))
$tileSize = 256 * $scale
$width = [int][math]::Round(($x1 - $x0 + 1) * $tileSize)
$height = [int][math]::Round(($y1 - $y0 + 1) * $tileSize)
$bitmap = New-Object System.Drawing.Bitmap($width, $height)
$graphics = [System.Drawing.Graphics]::FromImage($bitmap)
$graphics.Clear([System.Drawing.Color]::Black)
$graphics.InterpolationMode = [System.Drawing.Drawing2D.InterpolationMode]::HighQualityBicubic
$loaded = 0; $missing = 0
for ($x = $x0; $x -le $x1; $x++) {
  for ($gy = $y0; $gy -le $y1; $gy++) {
    $tmsY = [int]$n - 1 - $gy
    $path = "D:\GIS\GIS\yuanlingPic3\$Zoom\$x\$tmsY.png"
    if (-not (Test-Path $path)) { $missing++; continue }
    $tile = [System.Drawing.Image]::FromFile($path)
    try {
      $left = [int][math]::Round(($x - $x0) * $tileSize)
      $top = [int][math]::Round(($gy - $y0) * $tileSize)
      $right = [int][math]::Round(($x - $x0 + 1) * $tileSize)
      $bottom = [int][math]::Round(($gy - $y0 + 1) * $tileSize)
      $graphics.DrawImage($tile, [System.Drawing.Rectangle]::new($left, $top, $right - $left, $bottom - $top))
      $loaded++
    } finally { $tile.Dispose() }
  }
}
$graphics.Dispose()
$format = if ([System.IO.Path]::GetExtension($Output) -eq '.jpg') { [System.Drawing.Imaging.ImageFormat]::Jpeg } else { [System.Drawing.Imaging.ImageFormat]::Png }
$bitmap.Save($Output, $format)
$bitmap.Dispose()
Write-Output "zoom=$Zoom x=$x0..$x1 googleY(top..bottom)=$y0..$y1 TMSY(top..bottom)=$([int]$n - 1 - $y0)..$([int]$n - 1 - $y1) dimensions=${width}x${height} loaded=$loaded missing=$missing output=$Output"