public List <Vector2> ComputeUVMap(HeightMap heightMap, TextureInfo textureInfo, int tileSize)
{
/**********************************
* We need to map texture pixels to heightmap points
* Linear mapping does not work because or Mercator projection distortion
* Pseudo code :
* for each point
* project to texture coordinates (pixelXY at same zoom than texture)
* get pixel offset from origin
* map this offset to (0 -> texWidth, 0 -> textHeight) => (0->1, 0->1)
*/
List <Vector2> uvs = new List <Vector2>(heightMap.Count);
var bbox = textureInfo.ProjectedBounds;
foreach (GeoPoint geoPoint in heightMap.Coordinates)
{
Point <double> projPoint =
TileUtils.PositionToGlobalPixel(new LatLong(geoPoint.Latitude, geoPoint.Longitude), textureInfo.ProjectedZoom, tileSize);
float xOffset = (float)projPoint.X - (float)bbox.xMin;
float uvX = MathHelper.Map(1, textureInfo.Width, 0, 1, xOffset, true);
float yOffset = (float)projPoint.Y - (float)bbox.yMin;
float uvY = MathHelper.Map(1, textureInfo.Height, 0, 1, yOffset, true);
uvs.Add(new Vector2(uvX, uvY));
}
return(uvs);
}
public BoundingBox ConvertWorldToMap(BoundingBox bbox, int zoomLevel, int tileSize)
{
var bboxTopLeft = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMax, bbox.xMin), zoomLevel, tileSize);
var bboxBottomRight = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMin, bbox.xMax), zoomLevel, tileSize);
return(new BoundingBox(bboxTopLeft.X, bboxBottomRight.X, bboxTopLeft.Y, bboxBottomRight.Y, bbox.zMin, bbox.zMax));
}
public TextureInfo ConstructTextureWithGpxTrack(TileRange tiles, BoundingBox bbox, string fileName,
TextureImageFormat mimeType, IEnumerable <GeoPoint> gpxPoints, bool drawGpxVertices = false, Rgba32 color = default(Rgba32), float lineWidth = 5f)
{
// where is the bbox in the final image ?
// get pixel in full map
int zoomLevel = tiles.Tiles.First().TileInfo.Zoom;
var projectedBbox = ConvertWorldToMap(bbox, zoomLevel, tiles.TileSize);
var tilesBbox = GetTilesBoundingBox(tiles);
int xOffset = (int)(tilesBbox.xMin - projectedBbox.xMin);
int yOffset = (int)(tilesBbox.yMin - projectedBbox.yMin);
//DrawDebugBmpBbox(tiles, localBbox, tilesBbox, fileName, mimeType);
int tileSize = tiles.TileSize;
var pointsOnTexture = gpxPoints
.Select(pt => TileUtils.PositionToGlobalPixel(new LatLong(pt.Latitude, pt.Longitude), zoomLevel, tiles.TileSize))
.Select(pt => new PointF((float)(pt.X - (int)projectedBbox.xMin), (float)(pt.Y - (int)projectedBbox.yMin)));
using (Image <Rgba32> outputImage = new Image <Rgba32>((int)projectedBbox.Width, (int)projectedBbox.Height))
{
foreach (var tile in tiles.Tiles)
{
using (Image <Rgba32> tileImg = Image.Load(tile.Image))
{
int x = (tile.TileInfo.X - tiles.Start.X) * tileSize + xOffset;
int y = (tile.TileInfo.Y - tiles.Start.Y) * tileSize + yOffset;
outputImage.Mutate(o => o
.DrawImage(tileImg, new Point(x, y), 1f)
);
}
}
outputImage.Mutate(o => o
.DrawLines(color == default(Rgba32) ? new Rgba32(1, 0, 0, 1f) : color, lineWidth, pointsOnTexture.ToArray())
);
if (drawGpxVertices)
{
PathCollection pc = new PathCollection(pointsOnTexture.Select(p => new EllipsePolygon(p, new SizeF(10f, 10f))));
outputImage.Mutate(o => o.Draw(GraphicsOptions.Default, Pens.Solid(Rgba32.Violet, 3), pc));
}
// with encoder
//IImageEncoder encoder = ConvertFormat(mimeType);
//outputImage.Save(fileName, encoder);
outputImage.Save(fileName);
}
return(new TextureInfo(fileName, mimeType, (int)projectedBbox.Width, (int)projectedBbox.Height, zoomLevel,
projectedBbox));
}
public byte[] GenerateTile(int x, int y, int zoom)
{
byte[] tileBytes = null;
var font = SixLabors.Fonts.SystemFonts.CreateFont("Arial", 12);
var corner = TileUtils.TileXYToGlobalPixel(x, y, TileSize);
var latLong = TileUtils.GlobalPixelToPosition(new Point <double>(corner.X, corner.Y), zoom, TileSize);
var latLongOffset = TileUtils.GlobalPixelToPosition(new Point <double>(corner.X + TileSize, corner.Y + TileSize), zoom, TileSize);
var graticules = graticuleService.DrawCore(latLong, latLongOffset);
using (Image <Rgba32> outputImage = new Image <Rgba32>(this.TileSize, this.TileSize))
{
string tileText = $"{x}/{y}/{zoom}{Environment.NewLine}";
outputImage.Mutate(o => o
.Fill(Rgba32.White)
.DrawText(tileText, font, Rgba32.Black, new PointF(10, 10))
);
outputImage.Mutate(o => DrawGraticules(o, graticules, corner, zoom));
// Test
if (DebugPoint != null)
{
var testPixel = TileUtils.PositionToGlobalPixel(new LatLong(DebugPoint.Latitude, DebugPoint.Longitude), zoom, TileSize);
var testTile = TileUtils.GlobalPixelToTileXY(testPixel.X, testPixel.Y, TileSize);
// Draw test pixel
if (testTile.X == x && testTile.Y == y)
{
var basex = TileUtils.TileXYToGlobalPixel(x, y, TileSize);
var ptLoc = new PointF((float)(testPixel.X - basex.X), (float)(testPixel.Y - basex.Y));
outputImage.Mutate(o =>
o.DrawLines(Rgba32.Blue, 1f,
new PointF[] { new PointF(ptLoc.X - 10, ptLoc.Y - 10), new PointF(ptLoc.X + 10, ptLoc.Y + 10) })
.DrawLines(Rgba32.Blue, 1f,
new PointF[] { new PointF(ptLoc.X - 10, ptLoc.Y + 10), new PointF(ptLoc.X + 10, ptLoc.Y - 10) }));
}
}
using (MemoryStream ms = new MemoryStream())
{
outputImage.SaveAsPng(ms);
tileBytes = ms.ToArray();
}
}
return(tileBytes);
}
public TileRange ComputeBoundingBoxTileRangeForZoomLevel(BoundingBox bbox, ImageryProvider provider, int zoom)
{
TileRange tiles = new TileRange(provider);
Point <double> topLeft = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMax, bbox.xMin), zoom, provider.TileSize);
Point <double> bottomRight = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMin, bbox.xMax), zoom, provider.TileSize);
BoundingBox mapBbox = new BoundingBox(topLeft.X, bottomRight.X, topLeft.Y, bottomRight.Y);
tiles.Start = new MapTileInfo(TileUtils.GlobalPixelToTileXY(topLeft.X, topLeft.Y, provider.TileSize), zoom, provider.TileSize);
tiles.End = new MapTileInfo(TileUtils.GlobalPixelToTileXY(bottomRight.X, bottomRight.Y, provider.TileSize), zoom, provider.TileSize);
tiles.AreaOfInterest = mapBbox;
return(tiles);
}
public TileRange ComputeBoundingBoxTileRangeForTargetResolution(BoundingBox bbox, ImageryProvider imageryProvider, int width, int height)
{
TileRange tiles = new TileRange(imageryProvider);
TileUtils.BestMapView(new double[] { bbox.xMin, bbox.yMin, bbox.xMax, bbox.yMax }, width, height, 0, imageryProvider.TileSize, out double _, out double _, out double zoom);
zoom = Math.Round(zoom, 0);
var topLeft = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMax, bbox.xMin), (int)zoom, imageryProvider.TileSize);
var bottomRight = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMin, bbox.xMax), (int)zoom, imageryProvider.TileSize);
var mapBbox = new BoundingBox(topLeft.X, bottomRight.X, topLeft.Y, bottomRight.Y);
tiles.Start = new MapTileInfo(TileUtils.GlobalPixelToTileXY(topLeft.X, topLeft.Y, imageryProvider.TileSize), (int)zoom, imageryProvider.TileSize);
tiles.End = new MapTileInfo(TileUtils.GlobalPixelToTileXY(bottomRight.X, bottomRight.Y, imageryProvider.TileSize), (int)zoom, imageryProvider.TileSize);
tiles.AreaOfInterest = mapBbox;
return(tiles);
}
private void DrawGraticules(IImageProcessingContext img, GraticuleLabels graticules, Point <double> corner, int zoom)
{
var font = SixLabors.Fonts.SystemFonts.CreateFont("Arial", 8);
foreach (var meridian in graticules.VerticalLabels)
{
var loc = meridian.worldLocation;
var pt = TileUtils.PositionToGlobalPixel(new LatLong(loc.Lat, loc.Long), zoom, TileSize);
var xpos = pt.X - corner.X;
var start = new PointF((float)xpos, 0);
var end = new PointF((float)xpos, TileSize);
img.DrawLines(Rgba32.Gray, 1f, new PointF[] { start, end });
try
{
if (xpos < TileSize - 10)
{
img.DrawText(Math.Round(loc.Long, 2).ToString(), font, Rgba32.Black, new PointF((float)xpos, 50));
}
}
catch (Exception)
{
}
}
foreach (var parallel in graticules.HorizontalLabels)
{
var loc = parallel.worldLocation;
var pt = TileUtils.PositionToGlobalPixel(new LatLong(loc.Lat, loc.Long), zoom, TileSize);
var ypos = pt.Y - corner.Y;
var start = new PointF(0, (float)ypos);
var end = new PointF(TileSize, (float)ypos);
img.DrawLines(Rgba32.Gray, 1f, new PointF[] { start, end });
try
{
img.DrawText(Math.Round(loc.Lat, 4).ToString(), font, Rgba32.Black, new PointF(50, (float)ypos));
}
catch (Exception)
{
}
}
}
public TileRange ComputeBoundingBoxTileRange(BoundingBox bbox, ImageryProvider provider,
int minTilesPerImage = 4)
{
// TODO good one, to test
// texture quality would be expressed in tex size
//TileUtils.BestMapView(new double[] { bbox.xMin, bbox.yMin, bbox.xMax, bbox.yMax }, 16384, 16384, 0, provider.TileSize, out double centerLat, out double centerLon, out double zoomBestView);
TileRange tiles = new TileRange(provider);
BoundingBox mapBbox;
Point <double> topLeft;
Point <double> bottomRight;
// optimal zoom calculation (maybe there's a direct way)
// see : https://docs.microsoft.com/fr-fr/azure/azure-maps/zoom-levels-and-tile-grid?tabs=csharp#tile-math-source-code (prepare tissues for nose bleed, and don't go if you're allergic to trigo and/or magical constants)
// calculate the size of the full bbox at increasing zoom levels
// until the full image would be greater than a tile
int zoom = 0;
int maxSize = 256 * minTilesPerImage; /* fixed to 256px to limit number of tiles */
do
{
zoom++;
// coords are pixels in global map image (see TileUtils.MapSize(zoom))
topLeft = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMax, bbox.xMin), zoom, provider.TileSize);
bottomRight = TileUtils.PositionToGlobalPixel(new LatLong(bbox.yMin, bbox.xMax), zoom, provider.TileSize);
mapBbox = new BoundingBox(topLeft.X, bottomRight.X, topLeft.Y, bottomRight.Y);
} while (zoom < provider.MaxZoom &&
Math.Min(mapBbox.Width, mapBbox.Height) < maxSize);
// now we have the minimum zoom without image
// we can know which tiles are needed
tiles.Start = new MapTileInfo(TileUtils.GlobalPixelToTileXY(topLeft.X, topLeft.Y, provider.TileSize), zoom, provider.TileSize);
tiles.End = new MapTileInfo(TileUtils.GlobalPixelToTileXY(bottomRight.X, bottomRight.Y, provider.TileSize), zoom, provider.TileSize);
tiles.AreaOfInterest = mapBbox;
return(tiles);
}
