National Map Production with Mapnik Rasterizer

&

Ordnance Survey Ireland

Vector to Raster

1:5000 Composite Raster Production using FME

IMGS

Ordnance Survey Ireland- National Mapping Agency

Ordnance Survey creates and maintains

Ireland’s mapping and related geographic

databases

Produces a number of mapping products in

a variety of scales in both digital and paper

formats

One of the main departments and products

produced by OSI are Large scale maps

(1:1000, 1:2500, 1:5000)

OSI Raster Mapping- 1:5000

OSI Raster product is derived from vector data and reproduced like for like

The existing vector (point, line, polygon and text) dataset is coded to represent

topographical features – Total of 130 possible layers

FEATURE_CODE DESCRIPTION GEOM

512 FENCE AND WALL POLYGONS POINT,LINE,POLY,TEXT

526 DECIDUOUS FORESTRY POINT,LINE,POLY,TEXT

527 CONIFEROUS FORESTRY POINT,LINE,POLY,TEXT

531 POLYGONS AND NAMES OF RIVERS POINT,LINE,POLY,TEXT

533 NAMES AND OUTLINES OF LAKES POINT,LINE,POLY,TEXT

550 MOTORWAY GEOMETRY POINT,LINE,POLY,TEXT

589 SOLID BUILDINGS POINT,LINE,POLY,TEXT

611 TOWNLAND BOUNDARY GEOMETRY POINT,LINE,POLY,TEXT

OSI Existing Raster Data

At present OSi prev have no

available resource to produce

a current 1:5000 raster product

Last produced in 2011, the

data is outdated

Poor Quality in areas

Existing OSi Raster Dataset is in use by emergency callout services, Fire,

Ambulance and Police

MapnikRasterizer

OSi turned to IMGS & FME to automate the provision of a country wide raster dataset

Use of Mapnik Rasterizer to style the 130 feature codes

There are 6,539 tiles covering Ireland, each measuring 4000m x

3000m (1200ha). Each tile represents a 1:5000 raster

Tiles are made up OSi Vector data in a combination of scales

1:1000, 1:2500 & 1:5000

OSI Raster Mapping 1:5000 Coverage

1:2500 & 1:1000 NTF Tiles

Mapnik High Level Process

A total of 80 style rules are created that have one or more layers

associated with each.

Build complex styles very easily using the symbolisers in Mapnik

and simple .png files

Most commonly used Symbolizers ;

LINE PATTERN

POLYGON PATTERNPOINT- TRANSFORM

Demonstration

Challenges Source Data

Source Data– Inconsistency

Data stored in wrong layer

Duplicated data- Both line and polygon

You can use any of FME’s 460 transformers to validate the data and correct it

to meet the requirements before processing to Mapnik- The output was

greater than then input

Challenges- Running the data

The volume of data required to be processed needed a automation workspace and

run on Server

End Result

Vector GeoTIFF

Why is this transformer so powerful?

Graphic interface for

Mapnik

Sophisticated symbols &

Shading

Transformation

Possibilities

Automation