Is porting the web client to JS feasible?

[gijs]

Hi!

Thanks for developing VTM! The HTML OSciMap client looks and performs great.

I'd like to build upon this project but I'm not a Java developer.

Do you think it's feasible to reimplement the web viewer using for example Three.js/Protobuf.js or vanilla JS/WebGL with the tessellate lib?

I have the modified TileStache instance up and running, serving the .vtm files, but for now I'm stuck looking at the Java code :)

Thx!

[hjanetzek]

Hi,

the WebGL port was really more a fun thing to see if this libgdx/gwt would actually work :) For javascript I would probably start with OpenLayers, then

1. write a tile decoder for pbf tiles to show geometries with ol vector layers
2. optimize the vector rendering. For this you could look through the renderer.elements package, I guess the most important optimization is to put all data for a tile in only few buffer objects to maximize batching of draw calls.
   compiling gwt in superdev mode will give you sourcemaps between the javascript/java sources directly in the browser debugger which might be helpful.
3. theming: this should probably not be ported, as there are already mapcss etc alternatives for js
4. drawing labels and label placement, the code in vtm is a good example how not to do it - I'm currently rewriting it from scratch..

Just curious, is your tile-server public - or what will be the purpose of your map?

[hjanetzek]

In case all you need a js api to the map and layers it may be possible to use https://code.google.com/p/gwt-exporter/ to export the necessary apis - This would require a bit of java hacking though

[gijs]

Thanks, that sounds interesting.
I'll dive into it when I find some spare time.