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Author Topic: Possible to get a colorid map to use black as "no plant" to keep scatter map too  (Read 540 times)

Screenscene vfx

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Heya Folks!

So I've been doing a few tests with forest and running through the forums just on a few basics. So the distribution maps are great as a starting point for over all natural variety, then having the colour map option as a way of positioning plants in specific areas makes things easier again. One thing that's a bit of a shame though, is in the documention on distribution map > diversity, it mentions using black on the colour map as a way of having blank or unplanted areas. From simple tests this doesn't behave as I'd initially think. What I thought was that I could place my colour map into the match color by ID slot in the diversity section only and have it use black pixels as a way of culling areas that I didn't want any plants in. This didn't behave at first with the black areas remaining planted but a quick search of the forum showed that I've got to put my colour map in the distribution map slot too and then use the threshold value to kill off the black areas of the map for planting.

Of course this means that I lose the option of using the various predefined scatter maps which is a pity. As a side fix I can use a contrasting colour instead of black as my empty area colour and then assign a new geometry type in the list matching this colour and set it to "disabled" which works fine, but it's a few extra steps that'd be great to skip. Would it be possible to add this feature in so we can keep all the nice scatter maps and use black in our "match color to id" maps to cull off areas? I know I can probably overlay the two maps into a composite to get it to work also but it'd be great to keep it all in the main ui!

Cheers,

John

iToo

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Hi, i just realized the documentation was wrong. The black pixel trick works for the Distribution Map, but not for the diversity. Apologies by that.

Anyway, there is an easier mode to get it: just assign a specific color (not black) with an item of type "Disabled" in the Geometry list. I've updated the documentation adding this procedure.

I hope that helps.
Carlos Quintero
iToo Software

Screenscene vfx

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Ah super!

It works totally fine which is great - what's the logic in forest behind it though? In my little test, I have a map with green, red and black areas in it. If I have three geometry objects in forest using red, green and blue (which is my disabled object) how does forest decide that the blue geometry is what it'll use in my black pixel areas?

Just out of curiosity more than anything!

iToo

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Forest matches each pixel with the most similar color in the Geometry List, but black color has not any special meaning for the diversity map.  So, in this case it works just because blue is the most similar color to black.

Anyway, i suggest to not use pure black (0,0,0) as color ID in the Geometry List, because you would get unexpected results editing the listbox. Instead, (1,1,1) or any other color will work fine.
Carlos Quintero
iToo Software