[Qgis-developer] Discussion: could Ice be used in Qgis ?

[Julien Michel]

Hi Qgis developers,

I wrote a small library called Ice which is able to render raster (and 
vector) data pretty fast with all sort of cool effects. It is a 
rendering engine which only depends on otb, opengl and glew. It does not 
depend on a specific graphical toolkit, and does not even come with its 
own OpenGl context. You can see it in action here [1] (the viewer you 
see in the video is actually ice demo viewer, based on glfw). Source 
code is available here [2].

The reason why I am writing to this list is that I presented a poster 
[3] and a demo of this library at foss4g europe last week, and Paolo 
Cavallini told me it could be of interest for Qgis, either to replace 
the current rendering engine (that is actually what we did for our own 
qt-based desktop software in OTB suite), or to provide an alternate 
viewer. Therefore, following his advice, I bring this to your wise 
attention.

Here is a quick pros and cons analysis (based on my user experience with 
qgis and my knowledge of ice).

Pros:
- It can handle multiple layer with on-the-fly reprojection
- It is quite fast to browse and navigate into raster data
- It allows for really responsive user interactions (like constrast 
editing operations for instance),
- It has some fun and responsive tools for in-dept dissection of raster data
- It is meant to be embedded in other software
- The code is quite compact : only a few classes

Cons:
- It is not as rich as Qgis current rendering modes (especially on the 
vector side, but on the raster side too) : no LUT, no labels ... And I 
am not sure it could be enriched with all these.
- It heavily relies on OpenGl and GLSL capabilities, and does not work 
well with remote desktop (ssh -X or other techniques),
- It comes with few dependencies, but OTB is a pretty big one still,
- It has only a few contributors (me and 2 or 3 other persons). On the 
other hand, I do not know how many Qgis developers can contribute to its 
rendering engine. This would make rendering engine a joint effort ...

This is only a FYI notice, not shameless advertisement : feel free to do 
wathever you think is best with it (including discarding this email and 
never talk about it again). But if you think this is interesting and 
want to discuss this in further details, I would be happy to do so.

Regards,

Julien Michel

[1] https://www.youtube.com/watch?v=DR8l-0WajTw
[2] https://git.orfeo-toolbox.org/ice.git
[3] 
http://fr.slideshare.net/otb/ice-lightweight-efficient-rendering-for-remote-sensing-images

-- 
Julien MICHEL
CNES - DCT/SI/AP