Per-pixel lit particles

First of all thank you for this useful library.

Sometime ago I read an article about using normal mapped billboards and particles to achieve cool lighting effects like smoke per-pixel lit by the fire of an explosion (The technique is also described on ShaderX 5 book).
The implementation shouldn't be hard, my question is: does spark allow custom shaders on its particles?

Thank you for your attention and best regards.

Hi, at the moment there's no shader management at all in SPARK. You can bind a pixel shader while rendering particles to perform special effect if you want (+ binding the normal map).

However for normal mapping, you ll need a normal for the billboard to transform the normal map in the world and as billboards in SPARK are oriented on CPU and the normal is not transfered (for bus transfer saving as lighting is not handled). But as the normal is already calculated (it is the look of the billboard transform), all you have to do is modified a bit the renderer to transfer the normal.

One thing on my TODO list for SPARK 2 is shader management to put some computation on GPU (like billboard orientation or even primitive construction via geometry shaders) and to perform build in effects (reflexion, soft particles, normal mapping, heat effect...). The thing is I m working on the lib in my spare time for free, so I cant tell you when this will be implemented.

Juff perhaps you could add a wiki to the website and show a roadmap somewhere for people to have an understanding of what you plan to do with Spark 2. Perhaps some developers will want to join you and help move the engine forward.

Anyway keep up the great work.

Jubei

Thank you for your prompt reply. As soon as I have SPARK implemented in the engine I'll try to modify the renderer to pass normals too.
If the results are good enough I'll post them!
Thinking of a Direct3D 10+ / OpenGL 3.2+ renderer would it be a good choice to implement only a point renderer and make all the work on geometry shaders?
Claudio