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Karro
06-26-2008, 01:19 AM
Okay...

Just a quickie. This didn't take a lot of effort. Took something like RobA's mountain tutorial, then used a burn tool to hollow out a crater at the top. Messed a bit with the side, and added a low-depth noise bump map, then created a bump map from the gray-scale image.

Added a second layer of colors for the lava with yellow and oranges and reds blended and blurred a little.

I can provide a more detailed process if requested... but it's far from perfect, just a quick test to see if the concept works.

4640

Steel General
06-26-2008, 07:10 AM
Well since I'm partly responsible for this "mess" :D , I'd love to see a step-by-step process for how its done, but I can wait until you refine it a little more.

jfrazierjr
06-26-2008, 09:00 AM
purdddy.....

I really like how you got the texture on all sides of the cone. I assume you have picked up on using the smudge tool on the base texture used for the bumpmap?

Karro
06-26-2008, 11:36 AM
Well since I'm partly responsible for this "mess" :D , I'd love to see a step-by-step process for how its done, but I can wait until you refine it a little more.

I will try to get some snap-shots of the in-progress later today. I think this was relatively simple...


purdddy.....

I really like how you got the texture on all sides of the cone. I assume you have picked up on using the smudge tool on the base texture used for the bumpmap?

You assume correct. I like the effect it has on mountains, and I appreciate the tip! :) (i.e. thanks for pioneering it)

jfrazierjr
06-26-2008, 12:00 PM
I will try to get some snap-shots of the in-progress later today. I think this was relatively simple...



You assume correct. I like the effect it has on mountains, and I appreciate the tip! :) (i.e. thanks for pioneering it)



Cool... glad you like it. I can't say I really pioneered it, I am sure others were doing it before I tried it, I just keep pushing it cause I like the effect so darn much. Of course, if you are really thankful, you could also send me some money(PM me for the address)... or rep at least.

Oh, and btw, I would probably also think about using the smudge tool to draw the cone color down the slope side to try to blend in more with the underlying grass coloration....

Joe

Karro
06-26-2008, 12:12 PM
Cool... glad you like it. I can't say I really pioneered it, I am sure others were doing it before I tried it, I just keep pushing it cause I like the effect so darn much. Of course, if you are really thankful, you could also send me some money(PM me for the address)... or rep at least.

Oh, and btw, I would probably also think about using the smudge tool to draw the cone color down the slope side to try to blend in more with the underlying grass coloration....

Joe

Rep I can handle... (at least now I can...). Money... well... I'm out of a job as of tomorrow, so I don't think that's in the cards.

Yeah, I'm not satisfied with the hard-line of mountain color, but it was late when I did this, and I wanted to see what I could do quickly. I will be going back to refine it...

Karro
06-26-2008, 03:54 PM
So... as promised, a quick step-by-step of the volcano:

Each of these images represents a different layer/step in the process. Generally, I copied a layer to make the changes necessary for the next step. The green part is just a layer in the background... I don't do anything with it, and most everything else is on a transparent layer over that (it's there in the image for contrast).


So, started with a blob of 50% gray where I'm putting my volcano:

4659

I use the Alpha select on the layer to get the whole blob, then I perform an angular gradient fill with black and white.

4660

I make a copy of this, and redo the angular gradient with two mountain colors (I'm mostly using colors from the city-map-palette available for DL in RobA's regional map GIMP tutorial). I keep both layers, but leave the B&W layer invisible.

4661

Then, using a copy of the B&W layer (which, to work on, now has to be visible, but it will be invisible in the final image), I use Joe's method of using the smudge tool to smudge up and down along the outside of the mountain cone. This will make those ridge ripples on the cone later. Then I use the dodge/burn tool, set to burn, and burn a small, darkened spot at the tip in the midst of the white. The burn is subtle, but I think you want it subtle, because too much will appear too deep on the bumpmap. I also went back around the edge of what will be our crater with the dodge tool (set to dodge) to lighten it up a teensy bit. I also did some Noise>Spreads and Gaussian Blurs at some point around here. You just kind of get used to doing those two, in that order, after going through RobA's tutorial.

4664

Then, I made a copy of the original gray blob (I kept a copy of it hidden in the background), and applied a bump-map filter using the previous layer.

4665

Set this layer to overlay, and hide all the other layers except this, the mountain color, and the green background. However, I didn't totally like the results of this (I think this is partially the source of the "floating mountain" phenomenon), so I went back to the B&W gradient. I'll show what I did next in the next post.

jfrazierjr
06-26-2008, 04:03 PM
So... as promised, a quick step-by-step of the volcano:

Each of these images represents a different layer/step in the process. Generally, I copied a layer to make the changes necessary for the next step. The green part is just a layer in the background... I don't do anything with it, and most everything else is on a transparent layer over that (it's there in the image for contrast).


So, started with a blob of 50% gray where I'm putting my volcano:

4659

I use the Alpha select on the layer to get the whole blob, then I perform an angular gradient fill with black and white.

If you have not already, try it with 50% gray and white instead of black and see what you think. I think it really helps to get rid of the "shadow" effect after you bump map the whole thing in the final "picture" Then you have less manual blending to do to get the colors drawn down, or at least I think so.




4660

I make a copy of this, and redo the angular gradient with two mountain colors (I'm mostly using colors from the city-map-palette available for DL in RobA's regional map GIMP tutorial). I keep both layers, but leave the B&W layer invisible.

4661

Then, using a copy of the B&W layer (which, to work on, now has to be visible, but it will be invisible in the final image), I use Joe's method of using the smudge tool to smudge up and down along the outside of the mountain cone. This will make those ridge ripples on the cone later. Then I use the dodge/burn tool, set to burn, and burn a small, darkened spot at the tip in the midst of the white. The burn is subtle, but I think you want it subtle, because too much will appear too deep on the bumpmap. I also went back around the edge of what will be our crater with the dodge tool (set to dodge) to lighten it up a teensy bit. I also did some Noise>Spreads and Gaussian Blurs at some point around here. You just kind of get used to doing those two, in that order, after going through RobA's tutorial.

4664

Then, I made a copy of the original gray blob (I kept a copy of it hidden in the background), and applied a bump-map filter using the previous layer.

4665

Set this layer to overlay, and hide all the other layers except this, the mountain color, and the green background. However, I didn't totally like the results of this, so I went back to the B&W gradient. I'll show what I did next in the next post.

Karro
06-26-2008, 04:29 PM
Continuing on...

So, I take a copy of this layer:
4675

to work on.

First thing I did was play with the color curves. The previous bumpmap had a steep drop-off at the outside edge of the cone, and I wanted to soften that up. To do that, I wanted to move the blacks mostly toward grays, which means making the left-hand side of the color curve go more flat looking. I also rounded out the tip of the right-hand side of the color curve, but left most of the rest a straight line.

Then, I used the smudge tool and rubbed in and out rapidly along the ouside edge of the cone, bringing some of the lights down and the darks up, as before, but breaking up the edge of the cone as much as possible.

I also decided I wanted lava spilling out one side of the volcano, so I picked a likely spot based on the lights and darks (remember, darker is lower on the bumpmap) and made sure to smudge and blur one edge of the crater edge. I did some more clean up work around the crater. It's probable I also did some more noise>spreads and gaussian blurs for a few pixels. I didn't keep a full accounting of these. The result:

4676

Then, I created a new layer filled with 50% gray, a ran a bumpmap filter using the previous result:

4677

This layer will be set to overlay.

Next, I took another copy of the original gray blob, created a new layer and filled with Render>Clouds set to maximum detail and X&Y and created a bumpmap layer (with a lower depth than the previous bumpmaps) on to the gray blob using the noise.

4678

This is also set to Overlay.

To get the original image, I had all three bumpmap layers set to overlay showing visible (I decided i needed both cone bumpmaps to make the volcano really pop) with the color layer and the green background layer all showing. The color layers need to be below the overlaying bumpmaps in the layer stack.

To finish, I create a new transparent layer above the other color layers but below the bumpmaps. I pulled up the plasma palette that comes pre-installed with GIMP, and I used this to select reds, oranges, and yellows for lava. So, using a small fuzzy/soft brush, I paint in yellows and oranges and reds in places I like (yellow toward the center, radiating outward toward reds). I do this will all the other layers showing, but on my new transparent layer. That way, I get the lava where I want it in the crater and running down the mountain. Once I have these colors in place, I do a tiny gaussian blur.

And that leaves us with the previous finished product.

To work on this a little, I went back to the mountain color layer and smudged and blurred the dark bottom edge of it. I also changed the mountain color's layer to "lighten only", which seemed to help get rid of the dark ring near the bottom.

4680

Karro
06-26-2008, 04:33 PM
And finally, I did a very low depth bump map over the whole green field... and ta da, here's the final result:

4686

(In reality, I'd do more to the green field, using more of RobA's Regional Map Gimp techniques.)

Karro
06-26-2008, 04:35 PM
If you have not already, try it with 50% gray and white instead of black and see what you think. I think it really helps to get rid of the "shadow" effect after you bump map the whole thing in the final "picture" Then you have less manual blending to do to get the colors drawn down, or at least I think so.

Yeah... I hadn't thought of doing the gradient from gray-to-white instead of black-to-white. But I had figured out that the dark blacks at the edge were what were giving me the occasional "floating mountain" problem.

Steel General
06-26-2008, 07:39 PM
Great work Karro! I appreciatee you taking the time to work this out and making it available,

Karro
06-27-2008, 10:14 AM
Great work Karro! I appreciatee you taking the time to work this out and making it available,

No problem. Glad to be of some help!