[josm-dev] GSoC: OpenGL view for JOSM

[Paul Hartmann]

On 10.03.2015 21:35, Michael Zangl wrote:
> Am 10.03.2015 um 16:42 schrieb Paul Hartmann:
>> I would be very interested in a basic benchmark / proof of concept!
>
> Here you go. Some hours of work, and JOGl renders basic lines. To make
> it fair, I removed everything except the line rendering from the Java2D
> renderer.

Wow, this was fast!

To get a fair comparison, you need to turn off anti-aliasing for Java2D 
(or turn it on for JOGL).

> The JOGL phase 1 contains creating the line geometry (computing
> positions on screen, ordering by layer, ...). This can be cached and is
> a quick and dirty solution currently (some hashtables, lots of temporary
> objects and no nice line caps). I think I can get that down to be more
> like the old values, but probably not as low as those are (for a
> re-render. Unchanged objects could be skipped in this phase, changing of
> objects after zooming delayed).
>
> Phase 2 is the time required to collect all triangle buffers and send
> them to the graphic card (no VBOs/optimizations used at the moment,
> those would speed up phase 2 even more...)

Now I'm curious how the code looks like. :) You can share it by forking 
the JOSM mirror on github and create feature branches (or simply attach 
diff-files). I think no one will mind if it is quick and dirty, as it is 
clear that this is a preliminary test.

And we could move the whole benchmark topic to a new ticket on JOSM trac 
as it may become a longer discussion.

Paul