Export Hair Particle Issue

[burnin]

Thanks @burnin,

This highlighted an issue with parents and children and how they are counted/calculated.
The hairs converging into the center was another issue which is solved now too.

:D
Nice, yes! ...  & don't mention it, i thank you!
:)

[Rac Leborg]

Thank you for all the time that you are spending on fixing this issue. Unfortunately, it is still not working for me. Anything over about 25,000 (5000 x 5)hairs and my system hangs, and even at lower counts it is still very unreliable. Maybe I have something wrong in my system configuration?

(edited) If I use cycles, then I have no issues even with overkill quantities of hairs.

[blanchg]

Please provide a log or a .blend file.  I can use 100,000 hairs no problem on a laptop (150 second export time).  Comparing to cycles is a bit unfair as it never exports the geometry for each hair before rendering.

[Rac Leborg]

Hi Blanchg

Firstly, sorry for making the comparison- no offense was meant, I am really enjoying learning Corona. I was just trying to give some info about what is happening. (I'm a newbie).

I don't know how to obtain a log file as, after waiting a few minutes into the EXPORT, if I click anywhere on the screen Corona hangs with that 'white screen of death'.

I have uploaded a blend file which is having the issues mentioned.

Thanks again for you help

[blanchg]

No offense taken :D sorry it is 5:30 in the morning here!

If you go window > toggle system console before you start the render the console will appear.  Then you can copy from that window by selecting the text.

Thanks for the .blend I will have a look and see.

[Rac Leborg]

5.30! I hope you weren't woken up by an alarm telling you that there's a newbie in the UK who hasn't got a clue ;)

I have done the 'toggle system console', but as soon as I hit EXPORT it closes, and then I can't open it again because Corona crashes.

I will try again tomorrow as it is about time here for me to hit the sack. So (goodnight) good morning and I hope there is a nice day ahead for you.

[blanchg]

Sadly I am on my way to work
Another way to see the console is to start blender from the command line.  Open File Explorer and navigate to your blender directory then in the path area type cmd.exe and press enter.

From there you can type blender.exe and hopefully blender starts up.

That way when blender crashes the command window will still contain all the logs.

[burnin]

@Rac Leborg

1. Enable:
- Binary Mesh Export
- Export Hair
- Stream Hair

2. Use correct path for Export. (clear the contents, just to be sure no mixing is involved)

3. Set Particle System Emission number to lower value, ie: 100 - for testing purposes, to see if it at least renders a small number, then gradually up the count to see where the limit is. Otherwise you could be waiting minutes & hours for an error, wasting your precious time.
Keep in mind - Exporting process runs on a single core (White Screen/Not Responding) - use more efficient methods & techniques to grow grass or hair or...

Result:

[Rac Leborg]

burnin, thanks for the advice. So far I am on about 15,000 hairs before it fails. Cleaning out the export folder definitely helps!

Cheers

[blanchg]

How much free disk space and how much free memory do you have?

[Rac Leborg]

8GIG RAM and 30gig Storage on an SSD.

I might have found myself a workaround?:

I can convert the particles to a mesh - which is almost instant, and renders ok. Blender still keeps the original hair particles, which I switch off for rendering.

[Rac Leborg]

.... actually, (sorry for this) but I don't think the workaround is working. I will try it out again tomorrow. :(

[blanchg]

How much of your memory is actually free (look in the windows task manager) and how much of your disk is free (the 30GB?)

[Rac Leborg]

I am only using 18% of the RAM when exporting and I have about 12gig  spare on the SSD.

[Rac Leborg]

I have attached an error message that I get with 15,000 hairs.

I have freed up my SSD so there is now 35 gigs spare on a 120 gig drive. 8gig ram with only 18% being used at maximum.

I have also reinstalled Blender and Corona, but sadly to no avail.

Thanks again for your relentless help.