[Award Winner] Mountain Technique using Wilbur and the Gimp

[Torq]

This tutorial is an attempt to explain the mountain style I have used in the March challenge entry. It assumes a working knowledge of Wilbur and the Gimp.

I will follow a step-by-step procedure spread over several posts. In this tutorial the syntax ">>" will be used to denote the selection of menu and sub-menu items.

Step1: Creating the Heightfield:

In Wilbur create an empty map and change the size (Surface>>Size) to 1024x1024.
Then generate the heighfiled (Filter>>Calculate Heightfield). This opens the Heightfield Computation window. Change the paramters by selecting Ridged Multifractal from the drop-down menu. Uncheck the Spherical Evaluation box and hit the scaling button. In the surface scaling window select Broken Value from the dropdown menu. Then press OK and watch Wilbur generate the terrain.

Fill the basins (Filter>>Fill>>Fill Basins). Use the default slope value of -1. Next select only the flat areas of the map (Select>>From Terrain>>Flat Areas). Once again use the default values. Then add some percentage noise to these areas (Filter>>Noise>>Percentage Noise). Choose 2 or 3% and press OK. Deselect the flat areas (Select>>Deselect).

The next step is to run the erosion filter (Filter>>Erosion>>Erosion Cycle). Use the default paramaters and hit the run button. This may take some time depending on your system's specs. Close the erosion window.

Change to a grey scale map (Texture>>Grey maps>>Height Map). Then save the map as 16bit .

You should end up with something that resmebles the map below.

In the next step we will be using Gimp. You can either use your own heightfield or the one below.

Torq

[guyanonymous]

I'm waiting with bated (or is it baited?) breath....

[Torq]

Step 2: Modifying the height field.

Open the greyscale map in Gimp. In order to increase the contrast and make the elevation effects stand out more it is necessary spread the grey map over the full range of black to white. To do this open the levels window (Colors>>Levels). The levels window is likely to look something like the first screen shot.

Pull the sliders inward to coincide with the beginnings of the curves on the graph as shown in the second screen shot.

Once you hit OK the result should have higher contrast and look something like the third screenshot below.

Torq

[Torq]

Step 3: The Ground Layer and the Height field

In this step you will create three distinct ground layers and apply varying layers of bump to them in gimp.

Firstly create a new layer above the greyscale map as shown in the first screenshot Completely fill it with a light green colour. You may have to alter the mode of the image to RGB to get colour (Image>>Mode>>RGB). Make sure that "Fill whole selection is selected". I have used a light green texture that is not too uniform, as can be seen from the second screenshot.

Then select bump map (Filters>>Map>>Bump Map) and use the greyscale map layer as the bump map as shown in the third screenshot. In the bump map window adjust only the elevation to around 38. Then hit OK and you should get a result similar to the fourth screen shot with the rive paths clearly evident.

[Torq]

Step 4: The High Ground Layer and the Heightfield

In this step we will create the next level, or higher ground and appy the bump map to it.

Firstly hide the ground layer you just created and select the heightfield as seen in the first screen shot below.

Then choose the "select by color tool" and check the "Feather Edges" box. Move the feather slider to about 30 and the threshold slider to about 90 as shown in the second screenshot. Then choose the lightest point on the heightfield and select by colour as shown in the third screenshot.

Then unhide the light green ground layer. Create a new layer above it and name it "High Ground". Then select the new layer it as shown in the fourth screenshot.

In the map window use the bucket fill tool to fill the selected area with a brown colour representing higher ground. I prefer to use lighter colours as lighter ones show off the bump map more effectively. The result should look something like the fifth screenshot.

The use the same bump mapping technique as in Step 3, applying the bump map to the new "High Ground" layer. This time the elevation is decdreased to

[Torq]

Here is the last screen shot that was supposed to be in the previous post.

Torq

[overlordchuck]

Ooooooh, this looks interesting...

[ravells]

At bloody last!!! Thank you for sharing your secrets, Torq!!!!

[Steel General]

Very cool - thanks for posting.

[Ascension]

Hey, alright...glad there's more. I spent all night last night messing around with stuff just based on the first post and a post on Wilbur rivers in the overchuck tut. If waldronate happens to stop by and read this...is Wilbur going to support more import formats? I'd like to be able to do up some clouds, tweak them, and then import them into Wilbur but I can't output to any of the formats with PS.