Flow map painting

slosh

So, I recently came across this allegorithmic section showing how you can paint flowmaps in substance painter:

https://support.allegorithmic.com/documentation/display/SPDOC/Flow+map+painting

I need to do flowmaps for hair at work so this seemed like a great way to do it.  While I am happy with the results, there were a couple things that bothered me and since I am a novice at SP, I was wondering if anyone had ways to make this easier.  I'll start by describing how I did it.

My basic workflow was to paint flow for a set of strands, start a new layer, do more strands on top, new layer, more strand on top, etc.  I did them as groups of strands to speed up the process.  For one set of cards, I usually ended up with 4 or 5 layers.  You can tell that in the normal channel, they blend together instead of layering which doesn't work for me so I had to export each layer separately, and then layer them in photoshop.  That was issue #1...is there a way to get them to layer in SP in the normal channel?  Issue #2 is that each stroke had a border of the default normal value around the stroke.  I don't know if there was a way to remove this but essentially, I had to erase that from every layer I exported in photoshop.  As you can see, doing this for every stroke is a major pain in the ass.  I'm just curious if anyone more experienced with painting flow maps in SP can help me out.

Thanks in advance!

Jerc

You can make sure the strands don't add up with each other by changing the normal map channel blending mode in the layers to Normal instead of the default NormalDetail blending mode.
Then about the flat normal color on the sides of your stroke, I would say it could be that your brush is too smooth and the border of the alpha is so dark that it barely paint any normal slope color. Try using an alpha that's pretty contrasted, maybe the same you used to create the hair strand color on the left.

slosh

Thanks Jeremie!  Oh, I didnt realize the normal layers were in any sort of a blending mode.  I coulda sworn they were all just set to normal but I'll check that for sure.  As for the brush alpha, the strand color on the left is the same stroke, its just the color channel vs the normal channel.

slosh

So I thought I'd post my method for doing a flow map in Substance Painter.  This is by no means a polished method and I'm mainly posting it to see if anyone can make the process smoother/faster or if there is a better way altogether.  I wrote it for my fellow team members who aren't  familiar with SP so I apologize for people who are experienced SP users.  I attached it as a PDF to avoid having to upload all the pics.  It occurred to me for the last step, you can use something like dilation in photoshop to have all your strokes bleed out and then blur the whole image as opposed to having the fill color that I used.  Let me know what you guys think or if you have any suggestions!  Despite the somewhat tedious process to make the flow map, I found that it made a substantial difference in how the hair looked with our anisotropic shader even with all my UV shells being vertically positioned.

Kapoff

I struggled a few times with flow map painting in Painter, I'll try your additional few steps, maybe it'll help.
Additionally, try the Krita normal painter brush. That thing (even if behaving oddly at times) it's very powerful.
Thanks for sharing Slosh.

Goeddy

slosh said:

So I thought I'd post my method for doing a flow map in Substance Painter.  This is by no means a polished method and I'm mainly posting it to see if anyone can make the process smoother/faster or if there is a better way altogether.  I wrote it for my fellow team members who aren't  familiar with SP so I apologize for people who are experienced SP users.  I attached it as a PDF to avoid having to upload all the pics.  It occurred to me for the last step, you can use something like dilation in photoshop to have all your strokes bleed out and then blur the whole image as opposed to having the fill color that I used.  Let me know what you guys think or if you have any suggestions!  Despite the somewhat tedious process to make the flow map, I found that it made a substantial difference in how the hair looked with our anisotropic shader even with all my UV shells being vertically positioned.

tbh this looks way too complicated for the result, i would suggest using flow map painter instead or even the old PS method seems a bit more straightforward even though it won't create very accurate results.

slosh

Goeddy said:

slosh said:

So I thought I'd post my method for doing a flow map in Substance Painter.  This is by no means a polished method and I'm mainly posting it to see if anyone can make the process smoother/faster or if there is a better way altogether.  I wrote it for my fellow team members who aren't  familiar with SP so I apologize for people who are experienced SP users.  I attached it as a PDF to avoid having to upload all the pics.  It occurred to me for the last step, you can use something like dilation in photoshop to have all your strokes bleed out and then blur the whole image as opposed to having the fill color that I used.  Let me know what you guys think or if you have any suggestions!  Despite the somewhat tedious process to make the flow map, I found that it made a substantial difference in how the hair looked with our anisotropic
shader even with all my UV shells being vertically positioned.

tbh this looks way too complicated for the result, i would suggest using flow map painter instead or even the old PS method seems a bit more straightforward even though it won't create very accurate results.

Your welcome to use whatever method you prefer but to me, this method is far better than the photoshop cone method IMO.  I have tried that and it's just not accurate enough for my tastes.  My tutorial may seem complicated but after you've done it once, there's not much to it.  I've done it for a number of hairstyles at work and it doesn't take me very long.

pmiller001

thanks for sharing this! I'm trying to get hair down, and I've been struggling for a while. a lot of the technical part of making art is a mystery to me and very fascinating. thanks again for this post!. will try when I get home!

aanselmo

Hi @slosh
This may come a bit late on the discussion but I have a question the may sound silly, I am trying to get a similar result to apply on a micro skin details, I found Adelle Bueno "Achieving High-Quality, Low-Cost Skin: An Environment Approach" and looks like it can be used in the same way, but my question is how is this kind of map applied on an shader?

Example: I get it is a normal map, but if I have a skin normal map, more 3 micro skin maps with and RGB map to separate the 3 micro, how is this flow/smear map connects to the  micro?

poopipe

you push the UVs along the vectors defined by the flow map. 

aanselmo

@poopipe
now sure if that's for me but if it is got me even more confused xD I wanted to know in what channel is used the flowmap and if can be used in marmoset or is something more complex as unreal or unity

poopipe

you need a shader that supports the effect. how you plug the information in will depend entirely on the shader. 

I don't use marmoset so can't comment but afaik nothing has shipped with Ue4 or Unity that supports flowmaps

aanselmo

Thanks @poopipe I though this would be a feature to be used in realtime engines

thomasp

poopipe said:

I don't use marmoset so can't comment but afaik nothing has shipped with Ue4 or Unity that supports flowmaps

the UE hair shader supports flowmaps. you just need to tick one of the option boxes to activate that.

that's also the only use-case i ever found for substance painter.

poopipe

aanselmo said:

Thanks @poopipe I though this would be a feature to be used in realtime engines

It is,  you just have to make the Shader yourself.  

Unless you're doing hair apparently 

aanselmo

Thanks @thomasp and @poopipe need to try it and see if it works the same way

DanaosC

You can generate flow maps from Arnold for Hair textures