Map Tile API Developer's Guide

Flow Tile (flowtile)

Description

Returns a transparent image with only traffic flow.

Format

Requests against this resource must follow the pattern summarized by the following formula:

https://{1-4}.traffic.maps.hereapi.cn
/maptile/2.1/flowtile/newest/{scheme}/{zoom}/{column}/{row}/{size}/{format}
?app_id={YOUR_APP_ID}
&app_code={YOUR_APP_CODE}
&{param}={value}

For information on how to construct the request, see Constructing a Request

Common URI Parameters

The following table lists the URI parameters that are common for all requests.

Table 1. Common URI Parameters
Parameter Type Description
col Integer (required)

col – can be any number between 0 and number of columns - 1, both inclusive.

The number of tiles per column is a function of the zoom:

number of columns = 2zoom
format String (required) Returned image format. The following image formats are supported:
  • png – PNG format, 24 bit, RGB
  • png8 – PNG format, 8 bit, indexed color
  • jpg – JPG format at 90% quality

Please note that JPG is recommended for satellite and hybrid schemes only.

map id String (required) Specifies the map version, either newest or with a hash value.

See also Map Versions.

row Integer (required)

row –  can be any number between 0 and number of rows - 1, both inclusive.

The number of tiles per row is a function of the zoom: number of rows = 2zoom .

scheme String (required) Specifies the view scheme. A complete list of the supported schemes may be obtained by using the Info resource.

Note: Be aware that invalid combinations of schemes and tiles are rejected. For all satellite, hybrid and terrain schemes, you need to use the Aerial Tiles base URL instead of the normal one.

Traffic Tiles and Map Tiles support the other traffic related schemes (normal.traffic.day, normal.traffic.night). In order to properly support the traffic overlay case where you would request a transparent traffic tile from Traffic Tiles and a base tile from Map Tiles, the Map Tiles also support these schemes, in addition to Traffic Tiles supporting them.

size Integer (required) Returned image size. The following sizes ([width, height]) are supported:
  • 256 = [256, 256]
  • 512 = [512, 512]
The following sizes ([width, height]) are deprecated, although usage is still accepted:
  • 128 = [128, 128]

Note: Raster coverage tiles (rctile, rconlytile and rcdistonlytile) only support 256 sizes.

zoom Integer (required) Zoom level of the map image. Minimum and maximum zoom levels are specified in the Info resource.

Mandatory Query Parameters

The following table lists the mandatory parameters that need to be specified with every request. Not specifying these parameters will make the system reject the request.

Table 2. Mandatory Query Parameters
Parameter Type Description
app_id String A URL-safe encoded string obtained during the application registration. See Acquiring Credentials for information on getting credentials.
app_code String A URL-safe encoded string obtained during the application registration. See Acquiring Credentials for information on getting credentials.

Note: Use of token is accepted although is deprecated

Traffic Specific Query Parameters

The following table lists parameters for traffic options.

Table 3. Traffic Specific Query Parameters
Parameter Type Description
min_traffic_congestion String (optional) Specifies the minimum traffic congestion level to use for rendering traffic flow. It accepts the following values:
  • free (default) – renders all traffic lines, which includes free flow, heavy, queuing and blocked traffic lines.
  • heavy – renders all heavy traffic, queuing traffic and blocked roads.
  • queuing – renders the queuing traffic and blocked traffic lines.
  • blocked – renders only the black traffic lines for blocked roads.

Optional Query Parameters

Table 4. Optional Query parameters
Parameter Type Description
ppi Integer Pixels per inch. Resolution that can be requested, valid values are:
  • 72 – normal, used by default if no value provided
  • 250 – mobile
  • 320 – hi-res
  • 500 – 500 ppi

Note: For mobile schemes only mobile ppi value can be used, for hi-res schemes only hi-res ppi value can be used. For carnav scheme and normal.day.custom only normal ppi is accepted.