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Author Topic: Road edges  (Read 836 times)


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Road edges
« on: February 06, 2023, 07:48:02 PM »
Hi! We are working a lot with roads and paths in our projects, and now I'm trying to utilize more of Forest Pack's potential to detail the outer part of the roads in a more realistic way. In connection with this, I have a few questions that I hope someone can elaborate on.
  • Using scale falloff on the grass towards the road side works good. Also using the tint by boundary-effect works (alone), just like in this tutorial: However, if I try to add another effect at the same time, like "tint by object", none of the two effects works simultaneously. Isn't it possible to use both "tint by boundary" AND "tint by spline" or "tint by object" on the same forest? If I for an example wanted the same tint effect on a box placed in the middle of the grass, or a stripe of yellow grass through the lawn, at the same time as using "tint by boundary"?
  • Basically I would like to build up the road ditch with forest pack, possibly with different objects for different parts of the ditch, controlled by a distance parameter. What would be the best workflow for this now in 2023? A little like in the mentioned tutorial above, but think the same effect types with different kind of models? (pebbles, small weed grass, the tinted scaled grass, and just some more variety, like in the real world)
  • And what about the latter (ditch) as a build in forest preset? *hopeful*


Paul Roberts

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Re: Road edges
« Reply #1 on: February 08, 2023, 12:18:49 PM »

Thanks for the questions.

You're right, the existing tint operations always overwrite any preceding effects. This can be fixed but it requires some changes to the effects code. In the attached examples you can generally do this by changing the tintstrength line to retain any existing tints. For example, the line below was adjusted by adding the text marked in Bold.

real tintStrength = max(easein(length(v),tintFalloff,0,0,1), fpItem.tintColor.x*RetainExistingTint);

RetainExistingTint is a new parameter I've added to the effect that allows you to include any existing colour effects on a scale from 0 (ignore previous effects) to 1 (include previous effects at 100% strength)

Please see the attached file to see it in action. We will adjust the included effects to include this attribute in future.

Regarding road verges, you might find this tutorial of interest

The only difference now is that I'd probably use Forest Sets to share the splines and surfaces between all the different FP objects.

I hope that helps, please let me know if you have any further questions.


Paul Roberts
iToo Software