Javascript API 7.x

Class: Image

bu.oblique. Image

The object that represents a single oblique image from Blom server. The object has an object with the metadata and do transformations for coordinates.

new Image(options)

Parameters:
Name Type Description
options bu.oblique.ImageOptions

Oblique image options. Take care that this options are not optional and must be present.
Source:
bu-oblique/obliqueimage.js
Fires:

Extends

  • ol.Object

Methods

computeShotDate()

Computes the shot date in the format YYYY-MM-dd.

Source:
bu-oblique/obliqueimage.js

fromLocalCoordToPixelCoord(coordinates)

Transforms coordinates from a local spherical mercator XY coordinate to pixel XY coordinates inside an oblique image. The oblique viewer uses internally a fake spherical mercator projection in which oblique images are rendered as if they where full earth images. This function translates that fake coordinates to pixel coordinates. Pixel coordinates have origin at left top corner. X increases to the right and Y increases to the bottom. Both always positive values. Local coordinates are as spherical mercator. Origin is at the center of the image and axis are cartesian.

Parameters:
Name Type Description
coordinates bu.Coordinate | Array.<bu.Coordinate>

Coordinates as XY in Spherical Mercator.
Source:
bu-oblique/obliqueimage.js
Returns:

Coordinates transformed as x, y in pixels.

Type
bu.Coordinate | Array.<bu.Coordinate>

fromLocalResolution(localResolution)

Converts from local fake resolution to real one.

Parameters:
Name Type Description
localResolution number

The local resolution in meters per pixel.
Source:
bu-oblique/obliqueimage.js
Returns:

The real resolution.

Type
number

fromPixelCoordToLocalCoord(coordinates)

Transforms coordinates from pixel XY coordinate inside an oblique image to a local spherical mercator XY coordinates. The oblique viewer uses internally a fake spherical mercator projection in which oblique images are rendered as if they where full earth images. This function translates pixel coordinates to that fake coordinates. Pixel coordinates have origin at left top corner. X increases to the right and Y increases to the bottom. Both always positive values. Local coordinates are as spherical mercator. Origin is at the center of the image and axis are cartesian.

Parameters:
Name Type Description
coordinates bu.Coordinate | Array.<bu.Coordinate>

Coordinates as XY in image pixels.
Source:
bu-oblique/obliqueimage.js
Returns:

Coordinates transformed as x, y in Spherical Mercator.

Type
bu.Coordinate | Array.<bu.Coordinate>

fromPixelCoordToWorldCoord(coordinates, dtm, local)

Transform XY pixel coordinates to world coordinates in lon-lat 'EPSG:4326' projection. Pixel coordinates XY are the coordinates used internally in oblique imagery. Pixel coordinates have origin at left top corner. X increases to the right and Y increases to the bottom. Both always positive values.

Parameters:
Name Type Description
coordinates bu.Coordinate | Array.<bu.Coordinate>

Coordinates in pixels.
dtm boolean

Indicates if service must use dtm in the transformation.
local boolean

Boolean param to indicate if transformation must be done locally.
Source:
bu-oblique/obliqueimage.js
Returns:

The transformed coordinates as longitude and latitude or a Promise that returns transformed coordinates.

Type
bu.Coordinate | Array.<bu.Coordinate> | Promise

fromRealResolution(realResolution)

Converts from real resolution to local fake one.

Parameters:
Name Type Description
realResolution number

The real resolution in meters per pixel.
Source:
bu-oblique/obliqueimage.js
Returns:

The local fake resolution.

Type
number

fromRealZoomLevel(zoom)

Converts from real zoom level to local fake resolution.

Parameters:
Name Type Description
zoom number

The real zoom level. Notice that numbers do not need to be integers.
Source:
bu-oblique/obliqueimage.js
Returns:

The local fake resolution.

Type
number

fromWorldCoordToPixelCoord(coordinates, dtm, local)

Transform world coordinates in lon-lat 'EPSG:4326' projection to XY pixel coordinates. Pixel coordinates XY are the coordinates used internally in oblique imagery. Pixel coordinates have origin at left top corner. X increases to the right and Y increases to the bottom. Both always positive values.

Parameters:
Name Type Description
coordinates bu.Coordinate | Array.<bu.Coordinates>

Coordinates as longitude and latitude.
dtm boolean

Indicates if service must use dtm in the transformation.
local boolean

Boolean param to indicate if transformation must be done locally.
Source:
bu-oblique/obliqueimage.js
Returns:

The transformed coordinates in pixels or a Promise that returns XY transformed coordinates.

Type
bu.Coordinate | Array.<bu.Coordinate> | Promise

fromWorldCoordToPixelCoordUsingGrid(coordinates)

Transform world coordinates in lon-lat 'EPSG:4326' projection to XY pixel coordinates using a transformation grid through a bilinear interpolation.

Input coordinates must be enforced to be inside the extent.

Parameters:
Name Type Description
coordinates bu.Coordinate | Array.<bu.Coordinate>

Coordinates as longitude and latitude.
Source:
bu-oblique/obliqueimage.js
Returns:

The transformed coordinates in pixels.

Type
bu.Coordinate

fromWorldSourceToLocalSource(source, opt_source)

Returns a new bu.source.Vector with the geometries transformed from world coordinates in 'EPSG:4326' lonlat to local spherical mercator XY coordinates. The oblique viewer uses internally a fake spherical mercator projection in which oblique images are rendered as if they where full earth images. This function translates pixel coordinates to that fake coordinates.

All features are cloned and input features are not changed.

Parameters:
Name Type Description
source bu.source.Vector

Input source with geometries in 'EPSG:3426' lonlat projection.
opt_source ol.source.Vector

Optional destination source. If no undefined then the transformed features will be added to this source instead of creating a new one, and the function return this source.
Source:
bu-oblique/obliqueimage.js
Returns:

The output source.

Type
bu.source.Vector | ol.source.Vector

getBestResolution(resolution)

Returns the best resolution for a given resolution value. The resolution is ensured to be inside the resolutions of this image. The returned result is a pair of values, the first is the real resolution in meters per pixel. The second is the fake resolution for the internal oblique viewer.

Parameters:
Name Type Description
resolution number

The resolution in meters per pixel.
Source:
bu-oblique/obliqueimage.js
Returns:

[realRes, fakeRes].

Type
Array.<number>

getExtent()

Returns the extent of the oblique image in 'EPSG:4326' lonlat.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
bu.Extent

getExtraZoomLevels()

Returns the number of extra zoom levels of the oblique image or zoom levels to add to default zoom levels. In the new zoom levels the tiles will be rescaled.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
number

getGrid()

Returns the grid to do interpolations as it is returned in the resolve function by bu.promises.oblique#getTransformationGrid. To load a grid first check if isLoadingGrid is false, then create a listener for the GRIDLOADED event, then call loadGrid, and then check in the listener if getGridError was null or not.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
Array.<Array.<bu.Coordinate>> | null

getGridError()

Returns the error requesting grid to do interpolations as it is returned in the reject function by bu.promises.oblique#getTransformationGrid. To load a grid first check if isLoadingGrid is false, then create a listener for the GRIDLOADED event, then call loadGrid, and then check in the listener if getGridError was null or not.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
Error | null

getHeight()

Returns the height in pixels of this image.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
number

getMetadata()

Returns the metadata of the oblique image.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
bu.ObliqueMetadata

getObliqueResolutions()

Returns an array with pair of resolutions in meters per pixel for each zoom level inside the oblique in descending value order. The first resolution in each pair is the real mean resolution for the oblique. The second resolution in each pair is the fake resolution that the ol.Map object uses to draw the oblique.

Source:
bu-oblique/obliqueimage.js
Returns:

An array of pairs of numbers. [[realRes0, fakeRes0], ..., [realResN, fakeResN]]

Type
Array.<Array.<number>>

getResolutions()

Returns the resolutions of the oblique image. An array with pair of resolutions in meters per pixel for each zoom level inside the oblique in descending value order. The first resolution in each pair is the real mean resolution for the oblique. The second resolution in each pair is the fake resolution that the ol.Map object uses to draw the oblique. [[realRes0, fakeRes0], ..., [realResN, fakeResN]]

Source:
bu-oblique/obliqueimage.js
Returns:
Type
Array.<Array.<number>>

getShotDate()

Returns the shot date in the format YYYY-MM-dd.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
string

getWidth()

Returns the width in pixels of this image.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
number

getZoomLevel(localRes)

Returns the zoom level of a given fake resolution.

Parameters:
Name Type Description
localRes number

The local resolution in meters per pixel.
Source:
bu-oblique/obliqueimage.js
Returns:

The zoom level or null if wasn't found.

Type
number

isLoadingGrid()

Returns if the image is loading a grid or not.

Source:
bu-oblique/obliqueimage.js
Returns:
Type
boolean

isPixelInside(pixel)

Returns true if the pixel coordinates are inside the valid portion of the oblique image. We are in the valid portion when we are inside a buffer of apercentage of the border defined in bu.OBLIQUE_BORDER_RATIO constant.

Parameters:
Name Type Description
pixel bu.Coordinate

Pixel coordinates XY. Coordinates here can be negative values. If that happens then the function returns false. X values inside a oblique are always positive, X increasing rightward and Y downward from origin that is at top-left corner.
Source:
bu-oblique/obliqueimage.js
Returns:
Type
boolean

isPointInsideExtent(point)

Returns true if the point coordinates are inside the extent of the oblique image. The extent is the minimum rectangle bounding the oblique image. This function do not ensure the point is inside the oblique.

Parameters:
Name Type Description
point bu.Coordinate

World lonlat coordinates.
Source:
bu-oblique/obliqueimage.js
Returns:
Type
boolean

loadGrid()

Requests a transformation grid for this image and loads it. When the new grid is lodaded the image notifies it with a GRIDLOADED event.

Source:
bu-oblique/obliqueimage.js

toRealZoomLevel(localResolution)

Converts from local fake resolution to real zoom level.

Parameters:
Name Type Description
localResolution number

The local resolution in meters per pixel.
Source:
bu-oblique/obliqueimage.js
Returns:

The real zoom level. Notice that numbers do not need to be integers.

Type
number