DMS IntraMaps v8 now has the ability to display base maps from Tile Mapping Services (TMS)
MapManger can be used to create a set of tiles to be served by MapServer as a TMS within the new feature Tile Manager. Tile Manager allows you to design a tile set from a MapManager MapFile with the option to set how many levels, image format and desired machine resources to use while creating the tiles.
Tile Manager also includes a statistics page to help you determine the disc space requirements of your tile set.
Tile Map Services (Google Maps, NearMap, Bing Maps, Open Street Maps, VicMap API) are a set of pre-rendered image tiles served by a map server. A set of image tiles are created for a sets of scale ranges covering the full extent of the data through to a view of smaller features.
The image tiles are cached by the user's browser which allow the user to have a full availability of the data once they are cached instead of the browser having to call the server to refresh the map based on the new extent when the map is panned or zoomed. This allows for a seamless user experience.
The TMS serves a set of pre-rendered tiles in the form of png / jpg images which are rendered for a set of scale ranges. Each scale level requires more tiles than the previous scale by a factor of 4 and a scale half of the previous.
Level 0 will include the full extent of your data. For most TMS this is a world view however this may be limited to a suburb or municipality.
Level 0 contains 1 tile showing the map at scale x,
Level 1 contains 4 tiles showing the map at scale x/2,
Level 2 contains 16 tiles showing the map at scale x/4,
Level 3 contains 64 tiles showing the map at scale x/8 etc.
Depending on your initial Level 0 scale to view Property Boundaries you may need up to 20 scale levels. The amount of tile images for this base map can be in the order of 500 Billion so disc space requirements on the server have to be elevated to house this data. Additionally the time to generate / re-generate these tiles can be enormous.
GIS Administrators should consider the following when deciding the use Tile Manager:
Ideally the data used in the BaseMap should be static so it does not have to be regenerated often. Aerial Imagery can be a good candidate for such map content.
TileManager is accessible once a map has been loaded from the tools menu:
If it is the first time the current map has been loaded in TileManager then the form will be set to '<unsaved configuration>' along with the best calculated settings. TileManager settings can be saved and re-used to regenerate tiles where data has been updated.
Saves the current Tile Manager settings for use at a later stage
Delete the saved settings
Activated once settings have been saved. This button launches a dialogue showing the required configuration to use the BaseMap in IntraMaps. The configuration can be copied / pasted into the BaseMap configuration in IntraMaps ConfigManager. Only base folder should be updated as per the URL directory mapped to your Save Folder.
Activated once settings have been saved. This button begins the tile generation process.
Since BaseMaps can consume a lot of space and resources on your server TileManager includes a Statistics page to help you calculate the space and time requirements for your BaseMap. This tool can help you determine how many levels you can fit within your server and how long they will take to generate / regenerate. It is recommended this used prior to generating any tiles.
TileManager Statistics initially estimates the statistics based off a standard system specification however you can do a real world test using the Calculate Statistics option. The Calculate Statistics option will generate a small batch of tiles on your server and use the performance to determine the time requirements.
Once you have generated your tiles you will want to use them in IntraMaps. The BaseMap Text button shows you the configuration to copy into IntraMaps ConfigManager. The only modification is the URL to access the tile folder. The GIS Administrator will have to configure the tile folder as set in the Save Folder form as a virtual directory in IIS. We recommend creating a 'Tiles' folder under the 'Intramaps80' virtual folder for consistency
Copy and Paste the configuration into a BaseMap page in ConfigManager with the amended URL
The MapFile used by TileManager will have to be created with care since the time to generate tiles can make revisions a drawn out process. Once you have determine how many levels you wish to have you will need to ensure you MapFile is configured with scale based rendering to suit your desired BaseMap scales.
You should consideration the following
Ideally a label should be located at a defined geographic location however due to MapServer's dynamic label generation attempts to create tiles will duplicate the labels in each tile. This can make very cluttered and useless tile images.
We recommend the following globally for all label configuration
Issue: Point Labels as placed around or over the point feature. When a point is on the board of two tiles the label will appear in both tiles which when combined will be side by side in the TMS
Resolution: Configure the buffer setting when generating tiles. The buffer will create a buffer around the tile extent to capture the label and place it in a consistent position. The buffer amount is in pixels and will depend on the label size.
When using a buffer (meta-buffer) the label will in some instance be cut in half. We have to configure the label to allow partial labels
Issue: Line Labels are affected
For repeat distance consistency:
For repeat distance consistency and text truncation:
For repeating labels truncation issue
Issue: Polygon Labels appear in every tile and / or are truncated at edge of tile
For repeating labels:
For truncated text: