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Absinth
11-05-2008, 03:31 AM
Hello fellow Cartographers,
I have a question. Does any of you know about tutorials that explain how to create brushes for GIMP? I just had the thought, that I could save much time, if I'd just save typical elements of my maps (examples available in my map-gallery (http://www.cartographersguild.com/album.php?albumid=47)) like houses, trees and so on as brushes. I'm sure some of you did the same. Any experiences, tips, comments and so on would be appreciated!

RobA
11-05-2008, 07:55 AM
Do you want plain brushes, image tubes/hoses, or rotating brushes?

(I have pointers for all of them...just let me know)

-Rob A>

Absinth
11-05-2008, 09:25 AM
I'm still a newbie, when it comes to the advanced stuff in GIMP. Sorry, RobA, but I don't know what an image tube/hose is, nor do I know about pointers. I guess you'll roll eyes when reading this... :)
But I downloaded your rotating brush script a few days ago, so that might be a start... :)

I'd like to turn different shaped houses into brushes, so I can vary them in size and place it easily on a map. I thought about doing this in different angles because I think that a "brush image" can't be rotated, right? If there'd be a way to make it somehow rotate-able, that would be even better.

jfrazierjr
11-05-2008, 09:42 AM
I'm still a newbie, when it comes to the advanced stuff in GIMP. Sorry, RobA, but I don't know what an image tube/hose is, nor do I know about pointers. I guess you'll roll eyes when reading this... :)
But I downloaded your rotating brush script a few days ago, so that might be a start... :)

I'd like to turn different shaped houses into brushes, so I can vary them in size and place it easily on a map. I thought about doing this in different angles because I think that a "brush image" can't be rotated, right? If there'd be a way to make it somehow rotate-able, that would be even better.

In GIMP, an image hose/pipe is similar in concept to an animated GIF. The Sparks brush that comes with GIMP is a good example. As you move your brush, a different "frame" of the image hose/pipe is spit out to the image. This is a great way to do things such as trees, etc. You could draw up several tree images and use them to create "random" forest by using a single animated brush that spits out the random tree frames as you move your cursor.

RobA
11-05-2008, 11:32 AM
To expand on what Joe said-

There are 4 basic brush types in Gimp.

1) Parametric - these you create simply by clicking the New Brush button in the brush pallet. This pops up a dialog to let you define how the brush looks:

7540

These are quite useful and often neglected. For example I have defined a number of calligraphic brushes in various "nib sizes" and angles that are handy in my brush dialog.

2) Image Based, Shape Only - Simply create a new greyscale image (NOT RGBA). Make sure it is flattened (one layer) and save it as a ".gbr" file in your brushes folder. The white corresponds to the transparent color and the levels of gray are used as value for the foreground color. when using this brush:
7541

3) Image Based, Colour - Simply create a new RGBA file and also make sure it is flattened to one layer and save it as a ".gbr". It will paint just like it looks, not respecting the foregound colour choice:
7543

Here is an example of those three in use:
7544

4) Image Hose - These are knows as animated brushes or angular brushes, or random brushes. They can be RGBA (like the vine brush) or B&W/alpha mapped. These will require a whole different post :)

-Rob A>

jfrazierjr
11-05-2008, 12:17 PM
4) Image Hose - These are knows as animated brushes or angular brushes, or random brushes. They can be RGBA (like the vine brush) or B&W/alpha mapped. These will require a whole different post :)

-Rob A>

Perhaps when you can find some time, you can do a short tut on your tree brush pipe you created? I generally know the process and have done a few, but newbies might welcome seeing a true master at work...

Absinth
11-05-2008, 02:48 PM
...but newbies might welcome seeing a true master at work...

I second that! I'm really baffled seeing so great replies to my newbie question and the effort you put in explaining the different brush types. Even with example pictures! This is just great! I couldn't ask for more!! Thank you very, very much! I'd like to somehow return the favour!

Judging by the explanations it seems to be the best to create an Image based , Shape only brush for houses, trees and so on? As I understood it, it'll be possible to fill in colours later, right?
And is it possible to rotate the so created image with the rotation tool?

jfrazierjr
11-05-2008, 03:19 PM
Judging by the explanations it seems to be the best to create an Image based , Shape only brush for houses, trees and so on? As I understood it, it'll be possible to fill in colours later, right?
And is it possible to rotate the so created image with the rotation tool?

I tend to prefer using color brushes for anything that's not going to be one color. If your idea is to create houses as in just plain shapes, then Shape only is fine. If you plan to actually create something that has some type of bump mapping or even lines to indicate roof slope, I tend to think more in terms of color. My shape only brushes just don't come out right for me when I try to apply some color to them. What might be nice is if you can map a greyscale brush to a gradient when you lay it down.

RobA
11-05-2008, 05:28 PM
A greyscale image brush gets turned into an alpha map brush in the colour set by the paint tool.

If you really want a greyscale brush that you coul then gradientmap or colorize later, mage it RGBA and have the colour all shades of grey.

I'll try and knock up a sample later.

-Rob A>

Absinth
11-06-2008, 03:23 AM
If you really want a greyscale brush that you coul then gradientmap or colorize later, mage it RGBA and have the colour all shades of grey.

I'll try and knock up a sample later.

-Rob A>

That would be very helpful! Thank you! :)

Absinth
02-10-2009, 12:57 PM
A greyscale image brush gets turned into an alpha map brush in the colour set by the paint tool.

If you really want a greyscale brush that you coul then gradientmap or colorize later, mage it RGBA and have the colour all shades of grey.


Using this technique, would it be possible to make a "house brush", that I could color later, depending on the style of map I'm creating?

mariahmc
03-05-2009, 04:34 PM
i dont know if anyone will even see this since its been months since a post on this one, but i have the exact same delima. i am making a map and want to have house brushes too! the color is an issue for me since its a pretty detailed map.

RobA
03-05-2009, 04:41 PM
I think so. What is the final result you are looking for?

-Rob A>