Unit OSM.SlippyMapUtils

Description

Uses

Classes, Interfaces, Objects and Records

Functions and Procedures

Types

Constants

Variables

Description

OSM map types & functions. Ref.: https://en.wikipedia.org/wiki/Tiled_web_map

based on unit by Simon Kroik, 06.2018, kroiksm@gmx.de which is based on unit openmap.pas https://github.com/norayr/meridian23/blob/master/openmap/openmap.pas New BSD License

Overview

Classes, Interfaces, Objects and Records

Name	Description
Record `TTile`	Properties of a map tile
Record `TGeoPoint`	Point on a map defined by longitude and latitude.
Record `TGeoRect`	Region on a map defined by two pairs of longitude and latitude.

Functions and Procedures

function RectFromPoints(const TopLeft, BottomRight: TPoint): TRect; inline;

function TileCount(Zoom: TMapZoomLevel): Cardinal; inline;

function TileValid(const Tile: TTile): Boolean; inline;

function TileToStr(const Tile: TTile): string;

function TilesEqual(const Tile1, Tile2: TTile): Boolean; inline;

function ToTileWidthLesser(Width: Cardinal): Cardinal; inline;

function ToTileHeightLesser(Height: Cardinal): Cardinal; inline;

function ToTileWidthGreater(Width: Cardinal): Cardinal; inline;

function ToTileHeightGreater(Height: Cardinal): Cardinal; inline;

function ToTileBoundary(const Rect: TRect): TRect;

function MapWidth(Zoom: TMapZoomLevel): Cardinal; inline;

function MapHeight(Zoom: TMapZoomLevel): Cardinal; inline;

function InMap(Zoom: TMapZoomLevel; const Pt: TPoint): Boolean; overload; inline;

function InMap(Zoom: TMapZoomLevel; const Rc: TRect): Boolean; overload; inline;

function EnsureInMap(Zoom: TMapZoomLevel; const Pt: TPoint): TPoint; overload; inline;

function EnsureInMap(Zoom: TMapZoomLevel; const Rc: TRect): TRect; overload; inline;

function LongitudeToMapCoord(Zoom: TMapZoomLevel; Longitude: Double): Cardinal;

function LatitudeToMapCoord(Zoom: TMapZoomLevel; Latitude: Double): Cardinal;

function MapCoordToLongitude(Zoom: TMapZoomLevel; X: Cardinal): Double;

function MapCoordToLatitude(Zoom: TMapZoomLevel; Y: Cardinal): Double;

function MapToGeoCoords(Zoom: TMapZoomLevel; const MapPt: TPoint): TGeoPoint; overload; inline;

function MapToGeoCoords(Zoom: TMapZoomLevel; const MapRect: TRect): TGeoRect; overload; inline;

function GeoCoordsToMap(Zoom: TMapZoomLevel; const GeoCoords: TGeoPoint): TPoint; overload; inline;

function GeoCoordsToMap(Zoom: TMapZoomLevel; const GeoRect: TGeoRect): TRect; overload; inline;

function CalcLinDistanceInMeter(const Coord1, Coord2: TGeoPoint): Double;

procedure GetScaleBarParams(Zoom: TMapZoomLevel; out ScalebarWidthInPixel, ScalebarWidthInMeter: Cardinal; out Text: string);

Types

TMapZoomLevel = 0..20;

PTile = ˆTTile;

Constants

TILE_IMAGE_WIDTH = 256;

TILE_IMAGE_HEIGHT = 256;

TileMetersPerPixelOnEquator: array [TMapZoomLevel] of Double =
  (
    156412,
    78206,
    39103,
    19551,
    9776,
    4888,
    2444,
    1222,
    610.984,
    305.492,
    152.746,
    76.373,
    38.187,
    19.093,
    9.547,
    4.773,
    2.387,
    1.193,
    0.596,
    0.298,
    0.149
  );

MaxLong = 180.0;

MinLong = -MaxLong;

MaxLat = 85.0511;

MinLat = -MaxLat;

Description

Functions and Procedures

function RectFromPoints(const TopLeft, BottomRight: TPoint): TRect; inline;

Construct TRect from two TPoint-s

function TileCount(Zoom: TMapZoomLevel): Cardinal; inline;

Returns count of tiles on Zoom level (= 2ˆZoom)

function TileValid(const Tile: TTile): Boolean; inline;

Checks Tile fields for validity

function TileToStr(const Tile: TTile): string;

Returns standartized string representation of Tile

function TilesEqual(const Tile1, Tile2: TTile): Boolean; inline;

Compares tiles

function ToTileWidthLesser(Width: Cardinal): Cardinal; inline;

Floor horizontal map coord to tile size

function ToTileHeightLesser(Height: Cardinal): Cardinal; inline;

Floor vertical map coord to tile size

function ToTileWidthGreater(Width: Cardinal): Cardinal; inline;

Ceil horizontal map coord to tile size

function ToTileHeightGreater(Height: Cardinal): Cardinal; inline;

Ceil vertical map coord to tile size

function ToTileBoundary(const Rect: TRect): TRect;

Align absolute map rect to tile boundaries

function MapWidth(Zoom: TMapZoomLevel): Cardinal; inline;

Returns width of map at zoom level Zoom in pixels

function MapHeight(Zoom: TMapZoomLevel): Cardinal; inline;

Returns height of map at zoom level Zoom in pixels

function InMap(Zoom: TMapZoomLevel; const Pt: TPoint): Boolean; overload; inline;

Checks if point Pt is inside a map at zoom level Zoom

function InMap(Zoom: TMapZoomLevel; const Rc: TRect): Boolean; overload; inline;

Checks if rect Rc is inside a map at zoom level Zoom

function EnsureInMap(Zoom: TMapZoomLevel; const Pt: TPoint): TPoint; overload; inline;

Ensures point Pt is inside a map at zoom level Zoom, corrects values if necessary

Returns

Point that is inside a map

function EnsureInMap(Zoom: TMapZoomLevel; const Rc: TRect): TRect; overload; inline;

Ensures rect Rc is inside a map at zoom level Zoom, corrects values if necessary

Returns

Rect that is inside a map

function LongitudeToMapCoord(Zoom: TMapZoomLevel; Longitude: Double): Cardinal;

Converts geo coord in degrees to map coord in pixels

function LatitudeToMapCoord(Zoom: TMapZoomLevel; Latitude: Double): Cardinal;

Converts geo coord in degrees to map coord in pixels

function MapCoordToLongitude(Zoom: TMapZoomLevel; X: Cardinal): Double;

Converts map coord in pixels to geo coord in degrees

function MapCoordToLatitude(Zoom: TMapZoomLevel; Y: Cardinal): Double;

Converts map coord in pixels to geo coord in degrees

function MapToGeoCoords(Zoom: TMapZoomLevel; const MapPt: TPoint): TGeoPoint; overload; inline;

Converts map point in pixels to geo point in degrees

function MapToGeoCoords(Zoom: TMapZoomLevel; const MapRect: TRect): TGeoRect; overload; inline;

Converts map rect in pixels to geo rect in degrees

function GeoCoordsToMap(Zoom: TMapZoomLevel; const GeoCoords: TGeoPoint): TPoint; overload; inline;

Converts geo point in degrees to map point in pixels

function GeoCoordsToMap(Zoom: TMapZoomLevel; const GeoRect: TGeoRect): TRect; overload; inline;

Converts geo rect in degrees to map rect in pixels

function CalcLinDistanceInMeter(const Coord1, Coord2: TGeoPoint): Double;

Calculates distance between two geo points in meters

procedure GetScaleBarParams(Zoom: TMapZoomLevel; out ScalebarWidthInPixel, ScalebarWidthInMeter: Cardinal; out Text: string);

Calculates parameters of map scalebar according to zoom level Zoom

Types

TMapZoomLevel = 0..20;

Map zoom. 20 = Maximum zoom among all tile providers

PTile = ˆTTile;

This item has no description.

Constants

TILE_IMAGE_WIDTH = 256;

Width of map tile in pixels

TILE_IMAGE_HEIGHT = 256;

Height of map tile in pixels

TileMetersPerPixelOnEquator: array [TMapZoomLevel] of Double =
  (
    156412,
    78206,
    39103,
    19551,
    9776,
    4888,
    2444,
    1222,
    610.984,
    305.492,
    152.746,
    76.373,
    38.187,
    19.093,
    9.547,
    4.773,
    2.387,
    1.193,
    0.596,
    0.298,
    0.149
  );

See https://wiki.openstreetmap.org/wiki/Zoom_levels

Level   Degree  Area            m / pixel       ~Scale          # Tiles
0       360     whole world     156,412         1:500 million   1
1       180                     78,206          1:250 million   4
2       90                      39,103          1:150 million   16
3       45                      19,551          1:70 million    64
4       22.5                    9,776           1:35 million    256
5       11.25                   4,888           1:15 million    1,024
6       5.625                   2,444           1:10 million    4,096
7       2.813                   1,222           1:4 million     16,384
8       1.406                   610.984         1:2 million     65,536
9       0.703   wide area       305.492         1:1 million     262,144
10      0.352                   152.746         1:500,000       1,048,576
11      0.176   area            76.373          1:250,000       4,194,304
12      0.088                   38.187          1:150,000       16,777,216
13      0.044   village/town    19.093          1:70,000        67,108,864
14      0.022                   9.547           1:35,000        268,435,456
15      0.011                   4.773           1:15,000        1,073,741,824
16      0.005   small road      2.387           1:8,000         4,294,967,296
17      0.003                   1.193           1:4,000         17,179,869,184
18      0.001                   0.596           1:2,000         68,719,476,736
19      0.0005                  0.298           1:1,000         274,877,906,944
20      0.00025 mid-sized bldng 0.149           1:5,00          1,099,511,627,776

MaxLong = 180.0;

Maximal possible longitude (inclusive)

MinLong = -MaxLong;

Minimal possible longitude (inclusive)

MaxLat = 85.0511;

Maximal possible latitude for used Web Mercator projection (inclusive)

MinLat = -MaxLat;

Minimal possible latitude for used Web Mercator projection (inclusive)

Author

Fr0sT-Brutal (https://github.com/Fr0sT-Brutal)

Generated by PasDoc 0.16.0.

OSM Map control

Unit OSM.SlippyMapUtils

Description

Overview

Classes, Interfaces, Objects and Records

Functions and Procedures

Types

Constants

Description

Functions and Procedures

Returns

Returns

Types

Constants

Author