Hello,
I’ve been following a few tutorials on Krakatoa as I’m new to it. I’ve found a few good ones but they use the collision test node in PFlow and for some reason it doesn’t work on mine. The particles don’t collide with whatever I’ve told it to (in this case a teapot) They just pass right through it. I’m using the demo version of Krakatoa 2.0 with 3DS Max 2012.
Any help on this would be much appreciated.
Thanks,
Jack
Not a bug 
If you go to the download page
thinkboxsoftware.com/krakatoa-downloads/
you might notice this text:
We felt that this feature is too powerful to just give away in the demo 
Oops my mistake, maybe I should check the text better next time!
You are such a tease though! Judging from what I saw in the tutorial the collision is very powerful, and so quick compared to 3DS Max’s standard deflectors and what not. If only I could afford a full version!
Whilst you’re here, I know you’ve answered this question before and you’re probably sick of answering it to noobs like me but could you take me through exactly how to partition particles? Here’s what I do,
I create a Pflow
I open Krakatoa and change the ‘Render Scene Particles’ to ‘Save Particles To Disk’
I then go to the Partition rollout and select how many partitions I want (in this case 10)
I leave everything else at the default
I chose a save path for the Partitions and then click Generate All Partitions Locally
After that I creat a PRT Loader at the origin
Load all of my Paritions and I can see them on screen perfectly, it is only showing a count of 14999 particles when my original Pflow had 150,000 and there should be 10 partitions of it so surely it should show 1,500,000?
However!
When I go to render, there is nothing there, no particles or anything. I was having this problem the other day when I just tried to render out some particles using Krakatoa and it wasn’t showing anything up.
Am I doing something wrong?
Thanks for you speedy reply!
Cheers,
Jack
Oh I forgot to mention as well, my particles don’t have a material on them. In the Krakatoa GUI, in the ‘Global Render Values’ I set it to Override the Colour with a plae blue colour. That still didn’t work, yet when I followed a tutorial, I got it to work and render perfectly. This is the tutorial vimeo.com/9647504
Thanks!
Hi Jack!
No problem, please feel free to ask as much as you want!
Your steps are correct, but here are some notes about the confusion points:
*When you create a PRT Loader, it is set by default to show 1% of all particles in the viewport, and 100% in the renderer. The 1% is based on the Render Count, so if you reduce the Render % to 50.0, you will see 0.5% of the particles in the viewport! You can change that, but it was made, like in PFlow, to speed up the display. The “Particle Counts” rollout in the PRT Loader will show you how many there are on Disk, how many will render and how many are shown in the Viewport. You can even plot graphs to see that all files are there for all partitions and frames, or even visualize the counts per frame.
*When you render, you need at least one light source. Krakatoa does not respect the default lighting (we tried, but it looked bad). So you MUST create a spotlight or omni light or something illuminating the particles, unless you enable either Use Emission and Override Emission to make the particles self-illuminated, or check “Force Additive Mode” which will make the particles additive and they will show up without lighting, but without the volumetric effects. If you render without light, the RGB buffer will be black, but there should be particles in the Alpha channel. Or you can change the color of the background color to something else to see the black particles. If you see no particles in Alpha or on a non-black background, something else would be off…
We have implemented a little helper in Krakatoa to answer these types of questions - in the Main Controls rollout, at the bottom, you can click the “Schematic” button. This will display a flowchart of the rendering stages of Krakatoa, and if there are any issues, the respective nodes will be RED. For example, if you don’t have any particles in the scene, the MEMORY POOL will be red and if you roll over with the mouse, you will see the text “WARNING: The scene provides NO PARTICLES. Please create/unhide/enable one or more particle sources.” If you don’t have a light source, the RENDER PARTICLES Node will be red and will say “WARNING: Particles will render BLACK RGB unless at least one Light is created or either “>Use Emission” or “>Force Additive Mode” is checked.”
Note that the last sentence is exactly what I told you above 
Not only does the Schematic tell you these things, it lets you quickly fix the missing light by adding a default one: Right-click the “Sort For 0 Lights” node and select “Create Default Spotlight”.
If the lighting was NOT your problem (I did not see you mentioning any lights in your post), please look at the Schematic flow after rendering and see what it says. It will show you how many particles (if any) were loaded into the cache and what else could be off…
Hope this helps!