Using Koordinat2 webapp to convert between SVY21 and geographical coordinates

This is a follow up to the original post https://dominoc925.blogspot.com/2021/02/koordinat2-webapp-for-geo-coordinates.html, which describes a generic coordinate conversion steps. This post shows how to specifically use the Koordinat2 webapp https://dominoc925-pages.appspot.com/webapp/koordinat2/default.html to convert from WGS 84 latitude, longitude coordinates to SVY21 projected easting and northing coordinates, and vice versa.

Select the WGS 84 lat, lon as the source coordinate system

1. Using a modern browser, open the url https://dominoc925-pages.appspot.com/webapp/koordinat2/default.html.
   
   The Koordinat2 web app appears in the browser.
   
   
   
   
   
2. In the Input Coordinates card, click the gears icon labeled 1 in the screen above.
   
   The Select Source Coordinate System dialog appears.
   
   
   
3. In the Search field, type in a partial string for the WGS84 latitude, longitude system, e.g. "4326" or "WGS 84".
   
   A list of matches appear.
   
   
   
   
   
   
4. Click the WGS 84 list item.
   
   The WGS 84 geographic coordinate system is selected.

Select the destination SVY21 coordinate system

1. In the Output Coordinates card, click the gear icon (labeled 2 in the screen below).
   
   
   
   
    
   
   The Select Destination Coordinate System dialog appears.
   
   
   
2.  In the Search field, type in a partial string for SVY21, e.g. "3414" or "SVY21".
   
   A list of matching coordinate systems appears.
   
   
   
3. Click the SVY21 / Singapore TM list item.
   
   The destination coordinate system is selected.
   
   
   

Performing coordinate conversions from latitude, longitude to SVY21

1. In the Input Coordinates card, enter the Longitude and Latitude values.
   
   The Longitude/Latitude coordinates are dynamically converted and displayed in the Output Coordinates card.
   
   
2. Optional. If you wish to see the location of the coordinates on the map, click the marker icon as shown below.
   
   
   
   
   
   The location is marked by a marker on the map.
   
   
   
   
   

Performing coordinate conversion from SVY21 to WGS84 latitude, longitude

If you wish to perform the reverse conversion, simply repeat the previous steps but reverse the coordinate system selections.

 

 

WebApp for Singapore Weather forecasts rewritten using Flutter

I thought the old Singapore Weather Nowcast WebApp at this site https://dominoc925-pages.appspot.com/webapp/weather_sg/default.html written using the AngularJS framework and Bootstrap was a good candidate for a Flutter app. So I rolled up the sleeves and rewrote it using Flutter. Now it has Material design and this is how it looks and works.

4 day outlooks

For the Flutter version, I included additional data from the National Environment Agency (NEA)'s 4 day outlooks with temperature, wind and humidity values.

2 hour nowcasts

The 2 hour weather nowcast is now displayed in a responsive 2 pane display.

On small screens, a tab bar will appear displaying the nowcast list and map on separate tabs. 

 

24 hour forecasts

The new 24 hour forecasts are separated by 3 tabs as shown in the screenshot below. Clicking each tab will show the forecast for that time period. And like the 2 hour nowcast display, the 24 hour forecasts display is also responsive to screen sizes.

To try out the new Flutter WebApp, visit this web site: https://dominoc925-pages.appspot.com/webapp/weather_sg/default.html.

How to add a Singapore OneMap tile layer to QGIS

Singapore OneMap provides a wide range of tile maps in difference color schemes that can be used in web map applications (with the proper attribution, of course). For more information about OneMap, visit the website https://docs.onemap.sg/maps/original.html. 

QGIS has functions to load and display maps from map tile providers such as OneMap. The following shows a few simple steps to connect and add a OneMap original tile layer to the map pane of QGIS.

1. Start up QGIS.
   
   
2. In the Browser panel, mouse left-click on the Tile Server (XYZ) node. Choose New Connection.
   
   The New XYZ tile layer dialog box appears.
   
3. In the text field, type in the URL of a OneMap tile layer, e.g. https://www.onemap.gov.sg/maps/tiles/Original/{z}/{x}/{y}.png.
4. Click OK.
   
   The New XYZ tile layer dialog box appears.
   
5. In the text field, type in a meaningful name, e.g. OneMap. Click OK.
   
   The tile layer is added to the Browser panel.
   
6. To display it in the map view, mouse double click on the added layer in the Browser panel.
   
   The OneMap tile layer is displayed.
   

WebApp for monitoring traffic incidents in Singapore

This web app allows users to monitor traffic incidents in Singapore including accidents, vehicle breakdowns, obstacles, road blocks, traffic diversions etc. in Singapore (updated every 2 minutes) on a Google Maps backdrop by subscribing to the traffic incidents geoRSS feed. The incidents are shown as clickable and color coded icons with tool tips. 


Clicking on the icon will bring up more details about the incident. 

Together with Google's StreetView, users can truly immerse themselves into the incident environment.

The traffic incidents are also shown as a list on the right pane. The list can be sorted by incident category, and date-time - either in ascending or descending order. Clicking the Maps hyperlink will automatically locate, zoom, and center the incident in the Map view.

The WebApp can be launched from this link http://dominoc925-pages.appspot.com/webapp/trafmon_sg/default.html

Trainsity Singapore MRT for Windows Phone 8

This is a Windows Phone 8+ app for displaying the Singapore MRT and LRT metro network maps. The maps are high resolution vector files instead of raster images; the file sizes are small and you can zoom closer without having the details becoming blurred or "pixelated", like bitmap images.  The maps also have some interactivity coded in - when the train station labels are touched (or clicked), an option menu will pop up. Users can then choose to send the station location to the external Maps app where they can visualize the surroundings and/or perform directions routing.


The following screenshots show how the app looks like on a Windows Phone 8 handset.
 
When a tile is tapped, the detail map view of the MRT line will appear, as shown below.

Tapping a labeled box on the map will display the MRT station on the external Maps application, as shown below.

 If you want to find how long it takes to travel from one station to another station, and the best route to take, simply swipe to the Route page. Then type in the From station and To station and tap the Execute icon.

Tapping the more details link will display the recommended route to take.

 The app can be downloaded from the Windows Phone store.

Trainsity Singapore Android app

This is an Android app that simply displays the Singapore MRT and LRT train network maps. The maps are high resolution vector files instead of raster images; the file sizes are small and you can zoom closer without having the details becoming blurred or "pixelated", like bitmap images. The maps also have some interactivity coded in - when the train station labels are touched (or clicked), an option menu will pop up. Users can then choose to send the station location to the Google Maps or the Google Street View apps, where they can visualize the surroundings and/or perform directions routing.


The following screenshots show how the app behaves on a mobile handset.


On tablets, the app will automatically configure itself as a two pane display, as shown below. An ActionBar toggle button can be used to toggle the map display from two pane to full screen.


The app can be download from the Google Play Store.