[Bf-committers] Particle experiments - looking for feedback

[Alex Mole]

Hi Leon

It should take about the same amount of time to work out the inverse 
transform and multiply two particle points as it does to transform four 
vertices of a quad [roughly speaking]. However, once the particle has 
been inversely transformed, it will work for every face in the object. 
So for an object with 50 faces, we're talking 2 inverse transforms vs. 
200 forward transforms. I'd say that'd be a speed improvement ;)

I don't know enough about the guts of Blender to say for sure, but AFAIK 
transforms are stored in component {translation,rotation,scaling} form 
as well as a matrix, so you should be able to trivially construct the 
inverse transform.

Again, feel free to ask for advice on this if you want it :)


Keep up the good work!

Alex


Leon Turner wrote:
> Alex - I wasn't sure whether transforming the particle co-ordinates /
> velocities to object space would help much, given that I need to cycle
> through many possible deflection objects. What do you think?