New to mapping software

[schuster]

I hope this is the right forum. If not, I won't take offense to an admin moving this thread.

I've never used mapping software in my life. I've drawn many RPG maps by hand, and I've used equations to generate a "map" with computer software for me for the purposes of physics, but all of this is so new to me. I have a very scientific backround and not much of an art one.

So I figured the best place to start would be one of the basic tutorials on this site, go through it, and figure out why I'm doing the things the tutorial says. When I can do it, I get why I'm doing it, but I can't always do it. Currently I'm working through RobA's tutorial, "Using GIMP to create an artistic regional map." I'm using GIMP 2.6.6.

In the four part pdf file, I'm stuck on the first part somehow. A few major hangups...

First I downloaded and imported the palette he provided, but I'm not really sure how to even use it. The palette editor is different from the one pictured in the tutorial. This is probably the simplest question, and to be honest, I haven't even gotten to the point where I need the palette, but since I'm making the post... If I need a color from the palette, I just click on it?

Second, I drew a rough map in paint for my coastline. He says add a new transparent layer, name it "Land" and trace the path of the coast. Then, go to Colors -> Invert. I ran through this part 3 times, and only once was that option available. The other two times, the invert option was greyed out. I can't figure out what I'm doing wrong. I did get it to work, but in the interest of learning, I'd like to know WHY it didn't work.

Third, on pg 14 of the first part of his tutorial, he creates a new layer called "Sea Noise" then merges it down with the "Sea Shape" layer. Then he duplicates this layer and renames it "Sea". Then he adds a layer mask and tells me to select "channel" and it should by default list the "Land Mask" channel. The problem is when I go to this menu, the channel select box is greyed out and I don't have the option to choose anything at all. For what it's worth, I only have a vague idea of what layers, masks, etc. are at this point. Can anyone explain why the box is greyed out?

I know I sound silly with all this, as most of you folks have worked with this software many times over, so I appreciate any and all replies in laymens terms. I've only tried to start using this stuff in the past week, and it's a bit overwhelming at first. So far, of all the tutorials I've found, they are either extremely simple or using terminology that I don't know yet.

Thanks in advance!

[jfrazierjr]

Ok.. few basics.

• Pallete = a collection of colors. GIMP comes with quite a few, and you can create you own. If you use the same x colors all the time, it's easier to create a pallete and save than to try to find the colors by the hex value.
• Layers = a stack. Things on top (higher up in the layer order) can cover things below it.
• Channel = a special type of layer made of a black and white image. Channels are created by creating a selection, and then using the Selection->To Channel menu item. Channels are one way to quickly create a mask.
• Layer Mask = a modifier to a layer that "masks" out part of an image from showing(see my sig for a tutorial on layer masks)

Note that channels and layers can be named. This is just informational data so you can keep them seperate and organized.

For the invert, it is only available if you have a layer or a channel selected. If there is no selection, it has no way to know what to invert.

[schuster]

Thanks for the reply! What I understand and don't, maybe it'll be easier for others....

Ok.. few basics.

• Pallete = a collection of colors. GIMP comes with quite a few, and you can create you own. If you use the same x colors all the time, it's easier to create a pallete and save than to try to find the colors by the hex value.
• Layers = a stack. Things on top (higher up in the layer order) can cover things below it.

• I get this stuff. A pallete is good cause the definition exists outside of image software. I figured out the layers thing pretty easily too.
  
  

  Channel = a special type of layer made of a black and white image. Channels are created by creating a selection, and then using the Selection->To Channel menu item. Channels are one way to quickly create a mask.

  From your description, I'm imagining a channel to be a way to allow bright and dark to flow through the layers underneath the channel. If the channel is really dark, the only the darkest parts of the layers beneath it get through. Vice versa for really light. This doesn't have to be an exhaustive definition, just a concept. Am I wrong?
  
  

  Layer Mask = a modifier to a layer that "masks" out part of an image from showing(see my sig for a tutorial on layer masks)

This makes a lot more sense. Somehow, you saying that a layer mask indeed partially masks a layer put two and two together in my mind. I told you I was new at this, heh.

For the invert, it is only available if you have a layer or a channel selected. If there is no selection, it has no way to know what to invert.

So I'm guessing I just didn't have it selected. I'll go back and give it another shot, thanks for the post!

[jfrazierjr]

From your description, I'm imagining a channel to be a way to allow bright and dark to flow through the layers underneath the channel. If the channel is really dark, the only the darkest parts of the layers beneath it get through. Vice versa for really light. This doesn't have to be an exhaustive definition, just a concept. Am I wrong?

Your a bit off. Remember I said a channel is "one" way to make a mask. The purpose of creating a(or multiple) channel is to be able to apply the same size/shape mask to multiple layers quickly. Think of channels as a layer mask "template" that you can reuse over and over.

[jfrazierjr]

Your a bit off. Remember I said a channel is "one" way to make a mask. The purpose of creating a(or multiple) channel is to be able to apply the same size/shape mask to multiple layers quickly. Think of channels as a layer mask "template" that you can reuse over and over.

Also, when you add a layer mask, anything on the layer mask that is white shows through totally, anywhere on the mask that is dark is totally obscured. Any color between the two (shades of grey), will be some level of transparency.

[schuster]

Thanks a lot for your help so far jfrazierjr. I'm working through the tutorial some more and I'm making some progress. Starting to understand why I'm doing stuff and what each thing does.

I'm stuck again at a pretty silly part though. In the second part of the tutorial, he says create a new layer and fill it with 50% grey. I've searched gimp, I've googled, I'm still not sure how to do it. How do I fill the layer with 50% grey?

[Alecthar]

Thanks a lot for your help so far jfrazierjr. I'm working through the tutorial some more and I'm making some progress. Starting to understand why I'm doing stuff and what each thing does.

I'm stuck again at a pretty silly part though. In the second part of the tutorial, he says create a new layer and fill it with 50% grey. I've searched gimp, I've googled, I'm still not sure how to do it. How do I fill the layer with 50% grey?

The gray on the palette that's part of the tutorial is 50% gray, but the meaning of the name is that it's the shade of gray that rests exactly in the middle between pure white and pure black. 50% gray is significant because, when using the "Overlay" layer mode, any shades darker than 50% gray darken the image, whereas shades lighter lighten the image. In an Overlay layer 50% gray is completely transparent, except that filters like bump mapping make it through to the layers below the overlay, thus giving you a good way to keep a bump mapped texture on a separate layer from a color, so that you can adjust texture or color without affecting the other.

[ravells]

Another way to fill a layer with 50% gray: Edit > fill > Use 50% gray (from the drop down menu at the top)

[Midgardsormr]

And a third way is to manually set up the gray in your color mixer, then use the paint bucket to fill. In RGB (red, green, blue) the gray you want is 128, 128, 128.

[RobA]

It has been posted before but bears repeating. Check out this tutorial if new to Gimp:
http://www.gimptalk.com/forum/beginn...rs-t34772.html

-Rob A>