[Award Winner] Eriond - A Tutorial for GIMP & Wilbur

[waldronate]

The process typically includes a "fill basins" step. This step fills basins. If you have a ring of land, it's making a basin. I'm not sure that there's much you can do with that process, unfortunately. Selecting an area to be processed does the full normal fill basins and then blends the old and new surface according to the selection, which will leave a steep cliff in the area. I should probably modify the processing on fill basins to allow for a true selection that will treat unselected areas as sinks and so allow for interior basins with a careful selection.

A nasty workaround is to duplicate your height map and cut a channel on one side of the ring in one of the maps and on the other side in the other map. Then process the two maps and blend them with an image editing tool. An ugly solution, but possibly workable.

[MarkusTay]

Okay, now that you've just explained to me whats happening mechanically, I think I can work around it.

The ring of land/mountains around the perimeter I actually got to come out okay after tweaking some settings, but the central sea (that Wilbur is seeing as a 'basin') and continents keeps getting filed in. I can pull the center mass out of the map and do it separately, and then blend them as you suggested. There is one isthmus that connects one of the continents to the outer ring, but I'll just have to fudge that somehow.

Thanks for your input - I think I picked the wrong world to use this tutorial on, but I'll keep at it.

[MarkusTay]

Well, chopping the middle of the map worked very well (I assume), and I will now treat it as two separate maps and add them back together - great suggestion.

Only problem I am having now is that when I go to add rivers, it only adds them to the ocean. Everything else looks like it worked fine (compared to the tutorial's illustrations), and yet, it decided to put the rivers in the ocean instead. Anyway to adjust something to make them find the land?

I have a feeling almost all my problems may have been from a very early mistake with the clouds layer, and now its catching up to me. Bear in mind I had to start with a map given to me, and not one that was randomly generated, so my clouds have no direct correlation to the terrain on the other layers. I tried to correct that as much as I could with the Airbrush (and got decent results), but its not as perfect as it would have been had everything been derived from the same initial clouds layer.

If there is no way of adjusting this better (to find the actual land LOL), then I may just go back to hand-drawing the rivers, which I don't think will be a big deal (or will it?)

EDIT:
Okay, by lowering the mathematics (a LOT) and only doing one erosion pass, I can get the start of a few nice rivers, but they are all very short. The only ones that go all the way to the sea are ones where the mountains happen to be really close to the sea. Hopefully, by adding this part, you guys will be better-able to figure out whats going on here... I think I am on the right track. I feel I may have to tinker with the cloud layer a bit more - although I've found when I 'lower' the coastal areas too much (darken them), they tend to blur with the sea and I get my original problem back (where Wilbur can't differentiate between the low-lying regions and Ocean).

[MarkusTay]

So I got to the part where I apply the gradients and all I get is this awful mess that looks like a neon-green glow. I've tried backing-up a few steps (fortunately I've learned to save A LOT), but no dice. I finally decided to start from scratch again and went through the entire tutorial from beginning to end with a fine tooth-comb, double-checking each step, and I get the same exact ugly mess. For the very first time in my life I feel stupid, because I can't even figure-out what is going wrong. Even adjusting the gradient didn't help (just made it worse, actually).

It was really hard just for me to get-through the Wilbur part, but I finally got decent results with that. However, I had to re-draw all my rivers by hand - the select-by-color option simply would not work (which was fine, because I had my own river layout planned, and just used the Wilbur one for inspiration). As I mentioned above, I had to tweak all the settings to get that part to work, which probably has something to do with why the later part isn't working. I have a feeling I am making some sort of very basic mistake here (perhaps going too dark with the mountain re-paint?)

Here is what I got after Wilbur -



And here is what I get after I apply the first gradient -



So any ideas of where I am going wrong? The corners don't matter at all - they will be blacked-out at the end, showing only the central circle with a small bit of land around the perimeter (its a flat discworld with a mountain-barrier).

Also, early in the tutorial (1st step really), you have us creating a land mask - at that point we have the land outline still active on our screen; are we supposed to hit 'Select All' before proceeding, or are we supposed to only be creating land-clouds within the land boundaries? From the illustrations, it looks as if the entire canvas should be covered with clouds. I've tried it both ways, and I am pretty-sure it makes no difference (in fact, it might even save a step later), but I just want to make sure I am following the tutorial PRECISELY the way you meant it to be.

Thanks in-advance for any advice you guys might offer - I'm at wits end.

[Falconius]

In the gradients you apply you have to adjust all the transitions (the little arrows) until the gradient looks right. The way I did it was to have the gradient editor open with the greyscale hight map to be changed then applied the gradient map, if it didn't look right I undid the colouring action, adjusted the gradient arrows and then applied the gradient map again. It takes a while but eventually it will look correct.

Also be sure to stick to the colour codes provided at first as they will come out looking good.

[MarkusTay]

Thanks for the quick response.

I tried playing with the gradients quite a bit last night - it only got worse. I'll try that again in a little while - right now I am picking back through the thread and seeing where others went astray to see if I can spot the problem. I have a feeling the bump-map isn't working at all (which I don't think is the whole problem, but combine that with the gradient issue and it might be).

I seem to be having a problem figuring out which layers AND channels should be 'on' and 'off' at which steps.

[Falconius]

What I found was that I needed to have the white and lighter sections for the heights taking up much of the bar, at least half if not more, and that the lower altitude colours were rather small and had to be minutely adjusted. For the picture you have though I think I'd extend the yellowish/brown area bigger taking a bit of white out and then lower the blue colour to just a sliver and start working from there.

[waldronate]

One thing that you might try is to look at a histogram of your altitudes, either in Wilbur (Window>>Histogram) or Photoshop. The number of altitudes at each altitude can offer a suggestion as to how many colors should be in that area (lots of samples near an altitude would need more corresponding colors in the gradient).

[MarkusTay]

Okay, Thanks.

I found a weird work-around, but it makes me think it IS a gradient issue - I added another layer on top of the Temperate layer; a white one and I set the opacity at 30%. Apparently, my map is just too damn dark. Its still far from perfect, but it looks a LOT better then it did. I think my 'working style' is the opposite of Arsheesh's - I work from dark to light when blending, and I think when he blended his mountains, he worked from the mountains outward (so he went from light to dark). My blending seems to have worked fine, but my map is much darker (comparing mine at certain steps to his illustrations). Any way to lighten up just the darker bits without washing-out the whole thing? What if I fiddled with the bump-mapping numbers? Or should I just keep tweaking the gradient?

I also had problems when I took it into Wilbur, but resolved that by tweaking the settings (had to go with lower numbers for the mathematics part). Splitting the map worked-out just fine (because of the earlier issue I had with the center becoming one huge basin). I'll keep playing with it for now...

[MarkusTay]

On pg.10 of the tutorial, at the very bottom of the first column of text (after figure 26), you say "Add the Rivers Mask layer mask to the Arctic layer." In the next step you have us adding a black layer mask to the 2 desert layers and the arctic layer. You can't add a mask to a layer that already has a mask (at least, its not letting me do so with GIMP 2.8 ).

What am I supposed to do at this point?

Also, are we supposed to just leave all the channels 'on' all the time? They are not applied to anything unless associated with a layer, correct?

Thanks again.

EDIT: P.S. - It was gradient issue... plus a couple of other things (like my map being over-all too dark). I had to REALLY finagle the gradients to get them to work with the extremely dark palette, but I think it came out okay.