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Author Topic: distribution maps  (Read 600 times)

CB4720

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distribution maps
« on: October 14, 2015, 11:20:14 AM »
Hi

Looking for some help with distribution maps in FP. It's for a tennis court, so i rendered a top view and thought i could then draw a distribution map on it in photoshop and use that to get some worn areas where the players mostly are.

When i add a distribution map, it tiles and doesn't fit the plane. it also doesnt have any kind of fall off with it, grey doesn't seem to do anything with the distribution.

So to fix the tiling, i used surface UV parameter like the documentation suggests, this then locks out most setting in distribution and i'm still stuck with this either grass or no grass problem. I want to create a patchy area, what am i doing wrong?

Thanks

Michal Karmazín

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Re: distribution maps
« Reply #1 on: October 14, 2015, 12:28:38 PM »
Hi,

Actually, for the Distribution Map, the Threshold value (by default set to 50) is used to evaluate if the item will be placed or not (ON x OFF).

Kind of wanted effect can be archived by combining multiple maps (like any procedural map & Noise under a Mix / Composite map) as described in this "Density by texture" post.

Anyway, for these purposes I would suggest you to use that map linked to Transform - Scale instead of as the main Distribution Map. Attaching screenshots showing mentioned differences (Distribution map x Transform - Scale map). Hope you'll find it helpful.

Regarding proper map channel mapping (as mentioned in our on-line reference guide):

"As alternative of using the X/Y values to define the density of the distribution map, it's possible to get the scale from the UV coordinates of the surface. This mode is useful to adjust the position of trees in more precise way, using a surface map as reference.

To use this mode, a surface object must be assigned in the "Surface" rollout. The Surfaces can work in two operation modes, XY or UV (defined in the Surface rollout):

    XY mode: the UV coordinates are taken from the map channel defined with this parameter.
    UV mode: the map channel 1 is always used, and this parameter is locked."


Best regards,

3dcrgr

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Re: distribution maps
« Reply #2 on: October 23, 2015, 11:13:33 AM »
What about the distribution not recognizing grey? For me distribution is never smooth. You can clearly notice it does not react to grey and only take black and white into calculation.

Michal Karmazín

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Re: distribution maps
« Reply #3 on: October 23, 2015, 11:39:43 AM »
Hi,

Well, not exactly. To determine from which "luminosity value" will be the colour value evaluated as white is the Threshold value used. As mentioned in our on-line reference guide:

"Threshold - Defines how the image pixels are converted to black/white levels when the bitmap is in grayscale or color mode."

On "white pixels" item will be placed (ON) and on "black pixels" empty space will be left (OFF).

On the image in the middle (14-10-2015 11-56-55.jpg) is the "map linked to Transform - Scale instead of as the main Distribution Map" technique mentioned above used.

Hope that clears it up.

Best regards,

3dcrgr

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Re: distribution maps
« Reply #4 on: October 23, 2015, 03:02:17 PM »
Thank you for your answer.
I will give a try to the scale instead of distribution.