By Tay Shi'an

IMAGINE spending hundreds of hours creating your very own map of Singapore, complete with street names, HDB block numbers, favourite food haunts, and even speed traps on the road - just for fun.

That's what Mr Ong Chee Chung, 38, has done, with the help of thousands of online enthusiasts who are equally mad about global positioning system (GPS) maps.

Mr Ong is the Singapore mapper for Malfreemaps.com, one of several thriving online communities for Singapore and Malaysia GPS maps.

These online communities, comprising purely of hobbyists, produce maps by compiling input and contributions from members, much like Wikipedia.

These maps can then be downloaded free and used on GPS devices including those in cars, and handsets.

Another enthusiast, Mr Chai Fee Yang, 39, who is a moderator for the larger Malsingmaps.com and also a regional mapper for Malfreemaps, said: 'The mappers are voluntary, the site administration people are voluntary.

'The key concept is sharing - information keeps flowing in from members. It's like a tree. You observe our map, every day it's growing. It feels very good.'

Mr Ong noted there are key contributors, like hobbyist Mr Chuah Yong Tian, 39, a contract manager, who has provided about 80 per cent of the polygons for the Singapore GPS map.

Mr Ong said that as of last week, the Malfreemap had over 14,000 roads and 21,000 points of interest, which is GPS lingo for landmark, like a building.

He tries to include each new member's contribution within a week it's uploaded to the website.

He releases an updated version on the website every Monday.

Now, the Singapore map is almost finished, with only areas like Serangoon and Simei which are lacking detail.

Of course, there are drawbacks.

Like online encylopaedia Wikipedia, the accuracy of the data might be suspect sometimes, as it is contributed by members.

There is also the thorny issue of copyright - where each of the thousands of contributors got their data from.

Some copy from other websites, which may have paid high licence fees to various companies and authorities for the information.

Said the Singapore Land Authority: 'Individuals and companies are free to collect map data in Singapore through their own means that do not infringe copyright.

'SLA advises the public and businesses to respect intellectual property rights and to obtain permission to reproduce proprietary material.'

His love

Still, for Mr Ong, an engineer, it is labour of love.

On average, he spends six to eight hours a day on his hobby. His working hours are to his advantage - he works 12 hour shifts, so he gets three to four days off a week.

Mr Chai, a production control manager, said he now spends about three to four hours a week on tracking and GPS mapping, down from his peak of three hours per day.

He admitted: 'You can get addicted.'

Fellow hobbyist Mr Ronnie Chua, an engineer in his 50s, has rented and driven cars with GPS in various US and European cities, like Boston, Las Vegas and Amsterdam.

He said: 'GPS opens the world to you. It allows you to venture with no fear of getting lost.'

How an online map is created

1. A member of the forum drives through the unplotted area. Using his GPS, he records a 'tracklog', which marks his position every second he drives. He marks landmarks he passes using 'way points' (flags). He uploads the file from the GPS to the Malfree forum for the mappers to collate. Using mapping software, Mr Ong imports the tracklog (the green lines) into the existing map.

2. By tracing the tracking, Mr Ong draws in the roads onto the map. He also adds landmarks, such as the bridge, as marked by the way points.

3. He opens the Google Earth feature on the mapping software, which overlays his GPS map with the satellite images. He then traces the shapes of any buildings or bodies of water. The shapes are called 'polygons' in GPS lingo.

4. He uses another software to convert the map into one that is readable on GPS devices. This is the new user version.

This article was first published in The New Paper.