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Author Topic: Probability Distribution Not Working?  (Read 278 times)

Alex.S

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Probability Distribution Not Working?
« on: May 29, 2019, 03:30:13 PM »
Could someone tell me why 75% or so of the objects in this are the teapot, despite having even probabilities?

All I've done is enable collisions to make sure objects don't overlap.


RealViz

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Re: Probability Distribution Not Working?
« Reply #1 on: May 29, 2019, 04:35:24 PM »
Could someone tell me why 75% or so of the objects in this are the teapot, despite having even probabilities?

All I've done is enable collisions to make sure objects don't overlap.
You have to small density. More then 99% are eliminated by collisions. Use Forest Lister and green dot after name to see what happend wit your FP.
If you set Density from 100m to 1000m everything is OK.

Alex.S

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Re: Probability Distribution Not Working?
« Reply #2 on: May 29, 2019, 04:47:17 PM »
If I increase the area size, I struggle to keep things as densely packed tho

RealViz

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Re: Probability Distribution Not Working?
« Reply #3 on: May 30, 2019, 07:52:42 AM »
If I increase the area size, I struggle to keep things as densely packed tho
But your density is toooooo low! You distribute 44 item but with this (100m) density you can distribute ca 10k items. ;-)

Alex.S

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Re: Probability Distribution Not Working?
« Reply #4 on: May 30, 2019, 11:12:38 AM »
Doesn't help with my issue. With higher values items clump together and are not evenly distributed.

If I need a single row of items, it leaves gaps.
« Last Edit: May 30, 2019, 11:14:39 AM by Alex.S »

RealViz

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Re: Probability Distribution Not Working?
« Reply #5 on: May 30, 2019, 11:29:02 AM »
Doesn't help with my issue. With higher values items clump together and are not evenly distributed.

If I need a single row of items, it leaves gaps.
Please describe what you want to achieve. At the same time, read how the FP distribution works.
https://www.itoosoft.com/tutorials/back-to-basics-distribution-maps

Alex.S

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Re: Probability Distribution Not Working?
« Reply #6 on: May 30, 2019, 12:56:38 PM »
I want the area uniformly filled as densely as possible with a distribution that reflects the nodes. As I increase the area size as you suggest the gaps between nodes becomes less uniform and they clump. Despite using a full distribution map with no gaps. To me it seems that the collisions should be calculated prior to the distribution culling.

RealViz

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Re: Probability Distribution Not Working?
« Reply #7 on: May 30, 2019, 03:25:53 PM »
Turn off collisions and use grid instead full. Like attached image.
edit: and see global scale options in geometry ;-)
« Last Edit: May 30, 2019, 03:27:25 PM by RealViz »

RealViz

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Re: Probability Distribution Not Working?
« Reply #8 on: May 30, 2019, 03:30:03 PM »
without global scale change:

Alex.S

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Re: Probability Distribution Not Working?
« Reply #9 on: May 30, 2019, 04:23:21 PM »
Well my real objects aren't all the same width..

FC1888

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Re: Probability Distribution Not Working?
« Reply #10 on: May 30, 2019, 05:41:03 PM »
If you want items distributed in an area, so they are uniformly spaced, maybe you should create an area, use that for the initial distribution, so you get at least one of each item, in that area... Now draw another area, where you want at the size you want.. Then return to the initial area, select the Forest object, then using Item Editor, move all the items to want to the new area and put them exactly where you want them. I have found this workflow, very useful when I have a list of plants/trees I want to use, but I want them planted in specific positions. I just create a large enough area, to scatter all the items I need, then using item editor, I can extract one of each, deleting the rest. Then position, scale and rotate, as many of each item, wherever I want, around the scene, without having to draw or create areas for them and if I want to add more items, I can use the initial area to scatter that, then extract one using item editor and delete the rest.. While I find forest pack great for scattering grass, gravel over an area, it's not so good at garden design, when you want specific plants only in certain positions.. like neatly in a row along one edge of a plot and taller plants at the back and shorter ones at the front. Also point cloud makes it difficult to see what plant is what, so having an area to one side, where I can place one of each and even use text to label them, helps a lot.

Perhaps it may not help withr your specific problem, but it's how I work on many projects.