Semantic Tile API . terraintiles

Instance Methods

get(name, terrainFormats=None, clientInfo_operatingSystem=None, clientInfo_apiClient=None, altitudePrecisionCentimeters=None, maxElevationResolutionCells=None, clientInfo_applicationId=None, clientInfo_platform=None, clientInfo_deviceModel=None, minElevationResolutionCells=None, clientInfo_userId=None, clientInfo_applicationVersion=None, x__xgafv=None)

Gets a terrain tile by its tile resource name.

Method Details

get(name, terrainFormats=None, clientInfo_operatingSystem=None, clientInfo_apiClient=None, altitudePrecisionCentimeters=None, maxElevationResolutionCells=None, clientInfo_applicationId=None, clientInfo_platform=None, clientInfo_deviceModel=None, minElevationResolutionCells=None, clientInfo_userId=None, clientInfo_applicationVersion=None, x__xgafv=None)
Gets a terrain tile by its tile resource name.

Args:
  name: string, Required. Resource name of the tile. The tile resource name is prefixed by
its collection ID `terraintiles/` followed by the resource ID, which
encodes the tile's global x and y coordinates and zoom level as
`@<x>,<y>,<zoom>z`. For example, `terraintiles/@1,2,3z`. (required)
  terrainFormats: string, Terrain formats that the client understands. (repeated)
  clientInfo_operatingSystem: string, Operating system name and version as reported by the OS. For example,
"Mac OS X 10.10.4". The exact format is platform-dependent.
  clientInfo_apiClient: string, API client name and version. For example, the SDK calling the API. The
exact format is up to the client.
  altitudePrecisionCentimeters: integer, The precision of terrain altitudes in centimeters.
Possible values: between 1 (cm level precision) and 1,000,000 (10-kilometer
level precision).
  maxElevationResolutionCells: integer, The maximum allowed resolution for the returned elevation heightmap.
Possible values: between 1 and 1024 (and not less than
min_elevation_resolution_cells).
Over-sized heightmaps will be non-uniformly down-sampled such that each
edge is no longer than this value. Non-uniformity is chosen to maximise the
amount of preserved data.

For example:
Original resolution: 100px (width) * 30px (height)
max_elevation_resolution: 30
New resolution: 30px (width) * 30px (height)
  clientInfo_applicationId: string, Application ID, such as the package name on Android and the bundle
identifier on iOS platforms.
  clientInfo_platform: string, Platform where the application is running.
  clientInfo_deviceModel: string, Device model as reported by the device. The exact format is
platform-dependent.
  minElevationResolutionCells: integer, The minimum allowed resolution for the returned elevation heightmap.
Possible values: between 0 and 1024 (and not more than
max_elevation_resolution_cells). Zero is supported for backward
compatibility.
Under-sized heightmaps will be non-uniformly up-sampled
such that each edge is no shorter than this value. Non-uniformity is chosen
to maximise the amount of preserved data.

For example:
Original resolution: 30px (width) * 10px (height)
min_elevation_resolution: 30
New resolution: 30px (width) * 30px (height)
  clientInfo_userId: string, A client-generated user ID. The ID should be generated and persisted during
the first user session or whenever a pre-existing ID is not found. The
exact format is up to the client. This must be non-empty in a
GetFeatureTileRequest (whether via the header or
GetFeatureTileRequest.client_info).
  clientInfo_applicationVersion: string, Application version number, such as "1.2.3". The exact format is
application-dependent.
  x__xgafv: string, V1 error format.
    Allowed values
      1 - v1 error format
      2 - v2 error format

Returns:
  An object of the form:

    { # A tile containing information about the terrain located in the region it
      # covers.
    "coordinates": { # Global tile coordinates. Global tile coordinates reference a specific tile on # The global tile coordinates that uniquely identify this tile.
        # the map at a specific zoom level.
        #
        # The origin of this coordinate system is always at the northwest corner of the
        # map, with x values increasing from west to east and y values increasing from
        # north to south. Tiles are indexed using x, y coordinates from that origin.
        # The zoom level containing the entire world in a tile is 0, and it increases
        # as you zoom in. Zoom level n + 1 will contain 4 times as many tiles as zoom
        # level n.
        #
        # The zoom level controls the level of detail of the data that is returned. In
        # particular, this affects the set of feature types returned, their density,
        # and geometry simplification. The exact tile contents may change over time,
        # but care will be taken to keep supporting the most important use cases. For
        # example, zoom level 15 shows roads for orientation and planning in the local
        # neighborhood and zoom level 17 shows buildings to give users on foot a sense
        # of situational awareness.
      "zoom": 42, # Required. The Google Maps API zoom level.
      "x": 42, # Required. The x coordinate.
      "y": 42, # Required. The y coordinate.
    },
    "name": "A String", # Resource name of the tile. The tile resource name is prefixed by its
        # collection ID `terrain/` followed by the resource ID, which encodes the
        # tile's global x and y coordinates and zoom level as `@<x>,<y>,<zoom>z`.
        # For example, `terrain/@1,2,3z`.
    "firstDerivative": { # A packed representation of a 2D grid of uniformly spaced points containing # Terrain elevation data encoded as a FirstDerivativeElevationGrid.
        # elevation data. Each point within the grid represents the altitude in
        # meters above average sea level at that location within the tile.
        #
        # Elevations provided are (generally) relative to the EGM96 geoid, however
        # some areas will be relative to NAVD88. EGM96 and NAVD88 are off by no more
        # than 2 meters.
        #
        # The grid is oriented north-west to south-east, as illustrated:
        #
        #     rows[0].a[0]      rows[0].a[m]
        #         +-----------------+
        #         |                 |
        #         |        N        |
        #         |        ^        |
        #         |        |        |
        #         |   W <-----> E   |
        #         |        |        |
        #         |        v        |
        #         |        S        |
        #         |                 |
        #         +-----------------+
        #     rows[n].a[0]      rows[n].a[m]
        #
        # Rather than storing the altitudes directly, we store the diffs between them
        # as integers at some requested level of precision to take advantage of
        # integer packing. The actual altitude values a[] can be reconstructed using
        # the scale and each row's first_altitude and altitude_diff fields.
      "rows": [ # Rows of points containing altitude data making up the elevation grid.
          # Each row is the same length. Rows are ordered from north to south. E.g:
          # rows[0] is the north-most row, and rows[n] is the south-most row.
        { # A row of altitude points in the elevation grid, ordered from west to
            # east.
          "altitudeDiffs": [ # The difference between each successive pair of altitudes, from west to
              # east. The first, westmost point, is just the altitude rather than a
              # diff. The units are specified by the altitude_multiplier parameter
              # above; the value in meters is given by altitude_multiplier *
              # altitude_diffs[n]. The altitude row (in metres above sea level) can be
              # reconstructed with: a[0] = altitude_diffs[0] * altitude_multiplier when
              # n > 0, a[n] = a[n-1] + altitude_diffs[n-1] * altitude_multiplier.
            42,
          ],
        },
      ],
      "altitudeMultiplier": 3.14, # A multiplier applied to the altitude fields below to extract the actual
          # altitudes in meters from the elevation grid.
    },
    "secondDerivative": { # A packed representation of a 2D grid of uniformly spaced points containing # Terrain elevation data encoded as a SecondDerivativeElevationGrid.
        # .
        # elevation data. Each point within the grid represents the altitude in
        # meters above average sea level at that location within the tile.
        #
        # Elevations provided are (generally) relative to the EGM96 geoid, however
        # some areas will be relative to NAVD88. EGM96 and NAVD88 are off by no more
        # than 2 meters.
        #
        # The grid is oriented north-west to south-east, as illustrated:
        #
        #     rows[0].a[0]      rows[0].a[m]
        #         +-----------------+
        #         |                 |
        #         |        N        |
        #         |        ^        |
        #         |        |        |
        #         |   W <-----> E   |
        #         |        |        |
        #         |        v        |
        #         |        S        |
        #         |                 |
        #         +-----------------+
        #     rows[n].a[0]      rows[n].a[m]
        #
        # Rather than storing the altitudes directly, we store the diffs of the diffs
        # between them as integers at some requested level of precision to take
        # advantage of integer packing.
        #
        # Note that the data is packed in such a way that is fast to decode in
        # Unity and that further optimizes wire size.
      "columnCount": 42, # The number of columns included in the encoded elevation data (i.e. the
          # horizontal resolution of the grid).
      "altitudeMultiplier": 3.14, # A multiplier applied to the elements in the encoded data to extract the
          # actual altitudes in meters.
      "rowCount": 42, # The number of rows included in the encoded elevation data (i.e. the
          # vertical resolution of the grid).
      "encodedData": "A String", # A stream of elements each representing a point on the tile running across
          # each row from left to right, top to bottom.
          #
          # There will be precisely horizontal_resolution * vertical_resolution
          # elements in the stream.
          #
          # The elements are not the heights, rather the second order derivative of
          # the values one would expect in a stream of height data.
          #
          # Each element is a varint with the following encoding:
          # ------------------------------------------------------------------------|
          # | Head Nibble                                                           |
          # ------------------------------------------------------------------------|
          # | Bit 0     | Bit 1        | Bits 2-3                                   |
          # | Terminator| Sign (1=neg) | Least significant 2 bits of absolute error |
          # ------------------------------------------------------------------------|
          # | Tail Nibble #1                                                        |
          # ------------------------------------------------------------------------|
          # | Bit 0     | Bit 1-3                                                   |
          # | Terminator| Least significant 3 bits of absolute error                |
          # ------------------------------------------------------------------------|
          # | ...
          # | Tail Nibble #n                                                        |
          # ------------------------------------------------------------------------|
          # | Bit 0     | Bit 1-3                                                   |
          # | Terminator| Least significant 3 bits of absolute error                |
          # ------------------------------------------------------------------------|
    },
  }