View Full Version : Wilbur : Blending existing shore lines

Greason Wolfe
04-15-2009, 07:08 PM
I'm hoping there might be an easy answer to this question.

I have an existing height map in bmp format that I like the looks of. The problem is that some of the shore lines and river edges are almost grossly cliff like instead of being gradual rises. I've experimented with Wilbur a bit to see if I could smooth this out some and have had no luck what so ever, so my question is;

Is there an easy way within Wilbur to smooth these areas out such that the shores along the rivers and coastal regions aren't so aggravated? I know I can do this sort of thing in my graphics editors, however, doing so steals some of the detail away from areas beyond these shore lines. I tried following Joe's latest tutorial (Fun with Wilbur 4), but that didn't seem to do the trick.

In a semi-related question, I've been fiddling with the Erosion Cycle in Wilbur and understand that this may take a while, but is there a definition of "a while?"


04-15-2009, 08:31 PM
I'm not sure I understand the part about some of the shorelines and river edges being cliff-like. That's usually because the input data has a step in values across that boundary (e.g. goes from 0 to 10 instead of 0 to 1). There might be a way to help using some texture-to-selection tricks but I'm not sure what it would do to the other parts of the data. Any chance of seeing a sample of the problem areas along with a sample of some not-problem areas?

I haven't used that feature for a long time so I can't recall the exact parameters at the moment, but in general, a while is "as long as it takes". Not helpful, I know, but how long will depend on the settings, your surface size, machine processor speed, and installed system memory. I vaguely recall that I had sort of abandoned that feature because it wasn't doing quite what I had originally intended.

Greason Wolfe
04-15-2009, 09:05 PM
I can most certainly work up some examples, but it will take a little bit. In brief, however, it isn't so much the step values as it is the grey-scale value. In this particular instance, I'm using grey-scale values from 33 to 0 to represent sea-level and below while grey-scale values of 34 and up are used to represent land mass. So, along the coast of a sea, lake or river, one would generally expect the value to go from 33 to 34 to 35 etc. What I have is a value jump from something like 33 to 53 which creates a ridge/cliff like effect instead of nice blended effect from low to high or vice-versa. Not sure if that explanation helps define the problem more clearly or not, but I will post some samples as soon as I get a chance.

I also fiddled around with the erosion cycle some more and discovered it was mostly my impatience (as if that is any surprise :lol: ). I've really gotta work on that.

Edit : So here is a basic sample of what I am working with. The area bordered in red is the break between sea-level and land. As you can see, the rgb value is jumping significantly, so despite having a constant step value, the break becomes rather pronounced. I was hoping that Wilbur might have a feature that would allow me to blend this out better in a timely fashion without altering the remaining elevations (i.e. mountain peaks). The worst case scenario is that I do it in a graphics editor over a few layers and blend them in until the lowest elevations look smooth, but that is going to be time consuming. My ultimate goal is to use Wilbur to see where the remaining rivers are most likely to occur before actually plotting them out for rendering in Terragen.


04-16-2009, 01:21 AM
I'm a bit confused. I loaded the image and the lowest value is 33 (the sea areas), followed by a slope from 33 to 60 that represents the hard slope that is causing your concerns, followed by what appears to be a regular terrain-type distribution. The problem area appears to be in the 33 to 60 area, correct?

If you want everything below 60 to be at 33 then do Filter>>Height Clip with Min=60 and Max=10000 followed by Filter>>Mathematical>>Offset with a value of -27. This operation will reduce the maximum height from 255 to 228, but that's fairly minor.

Greason Wolfe
04-17-2009, 11:35 AM
Blah, I probably should have posted the full image instead of just a small portion of it. In any event, I took some time to read through your tutorials (Fun with Wilbur part 4 in particular) and, with a little light opacity filling and some blending in Wilbur, I think I've managed to solve the problem. I am so glad I finally decided to sit down and experiment with Wilbur. I'll still be rendering in Terragen, but Wilbur is such a great addition to that process, can't thank you enough for your efforts Joe! And while I aint got much, here's all the rep I can give you.