As my daily work depends on planting objects (vegetation) using Particle System, I always find very limiting and time-consuming to manually adjust the particles count all the time as I progress with the scenery.
As I haven’t found any solution so far, I have refreshed my “so-so programming skills” and ended by creating a very simple, but at least for me very useful Blender (2.79) addon, which does this job for me. It is not especially beautiful piece of code, but I think it is very well optimized performance-wise (I tested it on my particles-heavy projects) and it appears to be working
Normally, you set the total Emmission Number to get a density you are happy with.
But as this is the constant number, the density gets lower as you Weight Paint more area (and vice-versa):
With the addon, you set the Density parameter instead, and the Emmission Number is adjusted accordingly:
- Install it as an usual Addon, search for Density and enable it
- The new Density settings can be now found in a Particle System tab
- Each Particle System has now it’s own Density settings (which can be Enabled or Disabled)
- Once enabled, the initial density value is set automatically to match the current density (so it doesn’t mess-up your work)
- If enabled, the Emmission Number is now controlled by the addon (so don’t modify it - it will be changed back until you disable the density option)
- The extra option Update Tolerance is an optimization feature and is useful when using high number of particles - it let’s you set a minimum difference (in percentage) between the configured density and the actual one before the count is updated); it is a global option (Addon Preference), so it will keep the same for all your Blender projects
- The density expects an even mesh as it is currently computed using the overal mesh area, not taking the actual vertex group area into account (this is TODO)
- As my programming skills are not exactly award-winning ones, maybe the script is doing something extra I am not aware of, so beware
NOTE: Use at your own risk!
Please be very careful when using the addon, nobody tested it extensively so far (except myself), so even though I haven’t found any bugs, there are almost certainly some - please report any issues you find!
I have placed the addon to Github and would be very happy is someone can test it and report any bugs.