Hidden Gimp

[Legacy_Tarot Redhand]

               

As it's free, the Gimp is used by a lot of people on. The thing is it may well be more powerful than a lot of people realise as quite a few features are not immediately visible and of some that are visible it may not be immediately obvious what they do. So what I plan to do in this thread is to present those features I know about at the rate of one a day for the next week or so. However, if you know of a less well used or less well known feature of the Gimp and I haven't posted about it at the time, feel free to jump in and post about that feature (but not more than one a day please).

 

Just to get the ball rolling so to speak... As this is the first post in this thread I am going to post about 2 different features, beginning in the next post. 

 

TR

               
               

               
            

[Legacy_Tarot Redhand]

               

Something I discovered by accident while looking through the menus. Gimp has its own version of layer styles. For those that don't know, in photoshop layer styles allow you to apply 1 or more effects to a layer all at once. I don't know how long the Gimp has had its own version as who looks in script-fu if you don't have anything extra in there? Anyway, it is and it is called 'layer effects'. It even appears to have the same options as PS. It just doesn't appear to work quite the same though. For example the 'Bevel & Emboss' feature appears to be mutually exclusive with a number of others. Also the 'drop-shadow' effect can produce a wierd moat-effect. Having said all that, it is still worth a look.

 

TR

               
               

               
            

[Legacy_Tarot Redhand]

               

Here is something I discovered on deviantArt.

 

When you go to change either the foreground or background colours in gimp, there is a useful hidden feature of the dialogue box that pops up. If you, like me, have never entered a colour code in hex you probably won't know about this. Instead of entering a code in this box, think about the name of the colour you want. Press the first letter of that name and wait a few seconds. A menu of colour names, all with that first letter will probably appear. You can now either select one of these colours or you can refine your selection by pressing one or more additional letters. Go ahead, try it. For example press 'K' and you will be offered but a single choice - 'khaki'. It is not perfect as there are a lot of missing colours ('ochre' for example) but it is worth exploring.

 

TR

               
               

               
            

[Legacy_rjshae]

               

I don't know if you'd consider these hidden, but here's a couple that I've used:

 

The GIMP "Make Seamless" filter under the Map sub-menu can convert ordinary texture images into seamless maps. You may need to fiddle with it a bit though to produce satisfactory images. But I've used that feature a ton. Sometimes I just need to make a texture seamless in one direction. To do that, I copy the texture multiple times along the opposite direction (in a suitably sized window) before applying the Make Seamless, then extract the texture from the middle of the row.

 

When I want to paint highlights and shadows on a diffuse texture, I add the UV Map file from Blender as a separate layer. I leave that on top while selecting the diffuse map layer, then do my painting on that. It's great for things like worn stone placeables.

 

The GIMP Normal Map plugin is invaluable for making normal map texture. Not sure how useful that is in NWN though.

               
               

               
            

[Legacy_Tarot Redhand]

               

Today I will talk about a little used selection method. We all know the 4 selection tools - rectangle, ellipse, free (aka lasso) and fuzzy (aka magic wand). Quick tip for the fuzzy select - if you hold down Shift, you can select further pixels/areas without losing your original selection. 

 

If you look in the Select menu you will see some others - by color and from path. There is however another method that you might find useful. It is right at the bottom of the Select menu - Quick Mask. In all probability you will never access it through that menu.

 

Here's how you use it. Before activating the Quick Mask you need to have one of two tools already activated (brush or eraser) and the foreground/background colours need to be set to black and white. To illustrate how this is used, I have made a quick little drawing. Please be aware that these images are done quickly just to illustrate this method. You can do much better.

 

 

And here is that little picture in a gimp window/workspace.

 

 

So why essentially show you the same thing twice? Well this second image shows you the way to access a Quick Mask quickly. Look in the bottom-left corner of this window, on the same level as the horizontal scroll-bar. You will see a tiny square made from broken lines. Clicking this square toggles the Quick Mask on (alternatively press Shift+Q).

 

 

Not only is the Quick Mask now activated but the little square is now made whole and coloured red. Now we will erase some of this red coloured overlay. You can use either the brush tool or the eraser tool to do this. With the brush tool, white erases and black will re-paint the red overlay wherever you paint. With the eraser tool the colours are reversed. In other words you can correct any errors you make. So let’s start...

 

 

I am using the brush tool but you get the same result when using the eraser tool.

 

 

Once you have done it will look something like this. Now we toggle the Quick Mask off...

 

 

Voila. The area that you cleared is now automatically selected. The thing is you can clear more than one part of the image at once and you can toggle the Quick Mask on and off at will until you are satisfied. OK, let’s clear the background. First invert the selection.

 

 

Now let's do color to alpha and

 

 

Remember, it may be called a mask but in practice it is a versatile method to select an arbitrary number of areas of an image. Also, this last image does not really relate to the preceding ones (I had an accident and needed to redo quickly).

 

TR

               
               

               
            

[Legacy_T0r0]

               

Great tips, keep them comin' !! 

               
               

               
            

[Legacy_Tarot Redhand]

               

Hidden in plain sight. The Gimp may be versatile for editing images but that is not all that it can do. It can also generate images and overlays for images. These can be found under the Filters/Render menu entry. As some of the entries can be somewhat cryptic here is a list of all but one of them, arranged by category.

 

Create a new image

    A Checkerboard - Filter/Render/Pattern/Checkerboard

    A Maze - Filter/Render/Pattern/Maze

    Crumpled Satin - Filter/Render/Satin

Use an image to create another image

    Circuit - Filter/Render/Circuit

Overlay a pattern on an image

    A Grid - Filter/Render/Pattern/Grid

    A Jigsaw - Filter/Render/Pattern/Jigsaw

    Spirograph - Filter/Render/Spirogimp

    Rays Radiating From Image Centre - Filter/Render/Line Nova

    Fog - Filter/Render/Clouds/Fog

Maths Based Images  

    Diffraction Pattern - Filter/Render/Pattern/Diffraction Pattern

    Random Pattern - Filter/Render/Pattern/Qbist

    2 Colour Pattern - Filter/Render/Pattern/Sinus

    Random Coloured Stripes - Filter/Render/Pattern/CML Explorer

    Random Zig-Zag Lines - Filter/Render/Lava

    Draw Geometric Shapes - Filter/Render/Gfic

    Draw a Sphere - Filter/Render/Sphere Designer

Fractals

    Flame Fractal - Filter/Render/Nature/Flame

    Iterated Function System - Filter/Render/Nature/IFS Fractal

    Mandelbrot etc. - Filter/Render/Fractal Explorer

    Plasma - Filter/Render/Clouds/Plasma

Clouds (Base image for creating, amongst other things, Starfields)

    Difference Clouds - Filter/Render/Clouds/Difference Clouds

    Solid Noise - Filter/Render/Clouds/Solid Noise

 

Please note that some that I've labled as being random may in fact be based upon fractal maths of a type that I am not familiar with.

    

TR

               
               

               
            

[Legacy_Bannor Bloodfist]

               

spanky spanky.... "all but one"... now you leave the open question in every readers mind about what the "one' is, and/or why it was left out? I am conflused enough by Gimp and the entire subject of generating textures, now I have to wonder what is missing?   Please fixy fixy so I am less conflused.

               
               

               
            

[Legacy_Tarot Redhand]

               

I left that particular one out because, even though I have stretched what I consider to be usable for NwN to the limit, I just cannot see it having any use. When I tried it, all it does is to produce a bunch of squares in a grid. If you are really interested (and even my feline curiosity no longer stretches that far) it is called Electronic and is found at - Filters/Render/Electronic.

 

BTW, a tiny bit extra on the fog (Fog - Filter/Render/Clouds/Fog). From the looks of it, it should be a great basis for making grunge/rust/slime/etc.

 

Today's installment will arrive later today... (I am probably going with something to do with the UI)

 

TR

               
               

               
            

[Legacy_Tarot Redhand]

               

Given the news of our impending eviction from here, I have decided to go with another topic instead (or to use a well known phrase from childrens TV - 'Here's one I made earlier...'). See next post.

 

TR

               
               

               
            

[Legacy_Tarot Redhand]

               

Consider this post as a bonus entry. The reason why I say this is because what I am presenting here is not really hidden. While it is good, the Gimp 2.8 (as it ships) is lacking when compared to, say, Photoshop. Fortunately we can go quite some way to fixing this. Because it is open source there is a plethora of add-ins and plugins for it. In fact there are so many that it could be a problem in choosing just which ones to install. Just on filters, it is quite easy to end up with as many filters as a pw player has portraits. I hope to address this by listing the 8 that I consider probably the most useful and which I have got installed on my gimp set-up plus 1 I haven't. Please note that I will, in most cases, only give a brief description of each one. I urge you to follow the links to those that interest you, for fuller information. Also remember that plugins, etc. only show up when you load the gimp after you have installed them.

 

One thing before I go on to describe these add-ons and that is where to install them to. With the Gimp you have a choice of 2 different locations. You can install them in the place where you installed the Gimp itself, but this is not really recommended. Alternately you can install them in the place set aside for user installed stuff - drive:/Users/your user name/.gimp-2.8/ (win7 location, other OS will have a variation on this) - where drive is the drive letter and your user name is just that e.g. Fred. Example - c:/Users/Fred/.gimp-2.8/. This is the recommended location even though Gimp doesn't really care. There is an exception that I will deal with later. Also with a couple of the add-ons there are installers so in these instances the choice is made for you.

 

I'll start with the one that I haven't installed although I'll give it an honourable mention - GIMP_ilkka_Pack_for_Win32. This is a large collection of other people's work. The reason that I haven't installed it is mainly that it hasn't been updated in quite a while and I have already installed newer versions of a lot of the contents of it. I therefore recommend that if you want to install it, you do so before installing any of the other things I mention in this post.

 

In view of the announcement about the impending demise of the Bioboards, the second add-on is slightly less important than before. Having said that I will still include it here. This plugin is called "Save For Web" and allows you to intelligently optimise (size vs. image quality) your pictures for posting online.

 

If you are into animation such as in relation to animated gif files, you need Gimp GAP. This package comes with some interesting extras. The link takes you to the latest version. Even though it was made for Gimp 2.6 it still works with 2.8.

 

Do you want to use Photoshop filters (8bf files) with gimp? At one time the plugin that you would have used would have been PSPI (link included in case you are using an ancient version of Gimp). It was not perfect and there were quite a few PS filters that didn't work with it. Unfortunately this (at least for me) does not work with Gimp 2.8. All is not lost. The solution is a plugin called "Shellout". This plugin allows you to pass an image (or layer) to another program and to automatically reload the altered image when that other program has finished with it. This was originally designed to just work with XNView but has since been expanded to work with other editors (and this list is extensible). Given that XNView can directly use 8bf (as can IrfanView) filters (and more of them work than with PSPI anyway), this is now the preferred way to use such filters with the Gimp.

 

Do you ever need to edit a number of files using the same steps with each of them? In order to batch process them as it were? This is where Bimp comes in. You can use any gimp command in the list of commands to be carried out (in theory at least, I haven't had a need to test this out). There is one major drawback in that you can only use a command once in any list of commands (I don't know why, it may actually be built into Gimp), so you may need to run this plugin more than once on a set of images to achieve what you want. That aside I still find this useful and TBH I have yet to come across (except possibly using actions in PS) any batch process that allows for asymmetrically resizing of an image.

 

The last of the single use plugins on my list is Liquid Rescale. This allows you to intelligently rescale an image. That is you can tell it to assign different levels of quality to different areas of the image being rescaled. You can even remove parts of an image as a function of the rescaling process. I am sorry that this short description doesn't describe it too well. Just follow the link for a much better explanation.

 

The next entry in this list is Gimp Paint Studio. Like GIMP_ilkka_Pack_for_Win32, this a collection of brushes, tools, etc. Unlike that package, GPS (unfortunate acronym) is all by a single author (AFAIK). The link provided takes you to an independent review as the download page is very terse in its description. There is a link to the download page included in the review. The only annoyance I have found with this package (so far at least) is that it replaces the default Gimp loading screen with one of its own.

 

This penultimate entry into my list is a biggy. It adds so much that any short description will not do it justice. G'Mic (short for GREYC's Magic for Image Computing) addresses (amongst other things) the Gimps lack of filters. Not only are there 450+ things to alter the image but you can record your own settings for them as additional presets. In addition to that this is entirely open source. Looking around the web this addon is universally praised. To get some impression of its capabilities please follow the link.

 

This final entry in the list is not last because I consider it the least useful. On the contrary this one adds quite a bit of functionality that is not included in the previous entries on the list. FX Foundry is a collection of over a hundred script-fu scripts that once added gets its own entry in the menu that runs across the top of Gimps window. The only thing that is possibly problematic is how to install it correctly. Which is why I left it until last, so that I can tell you how to go about installing it. It is not that difficult, just a little involved.

 

1. Download the FX Foundry zip archive

   
2. If the Gimp is already open at this point, close it

   
3. Extract the zip archive into a new folder in a location that you are not going to either move or delete

   
4. Launch the Gimp

   
5. Open Edit/Preferences

   
6. Expand the Folders entry (on the left at the bottom - click on the '+' sign.

   
7. Select Scripts

   
8. Highlight one of the paths (e.g. C:\Program Files\GIMP 2\share\gimp\2.0\scripts) under where it says Folders, by clicking once on it.

   
9. Now press the button that looks like a sheet of paper. It is immediately above where it says Folders and is the leftmost of those buttons. This will create a duplicate entry in the list of folders.

   
10. To the far right of the button that you just pressed is one with a folder icon. Press this button and use the dialogue that pops up to navigate to the folder that contains the FX Foundry scripts.

   
11. Once you have found and highlighted the correct folder press OK to close the folder browse dialogue and now that you have a new entry in the Preferences/folders/scripts dialogue, press OK here as well.

   
12. Close and relaunch the Gimp. Congratulations, you should now have a new entry in the top level menu (just to the right of Filters) and you have installed the FX Foundry package.

 

Finally, before I finish this post, here are a few more links. A lot of tutorials on Gimp can be found on deviantArt. In fact that is where I get most of my information. Quick tip - As the vast majority of these are in the form of image files, where possible, I use Foxit Reader to convert them into pdf files as I find them easier to view and manage (and pdf readers tend to remember my view settings). deviantArt also has quite a lot of Gimp brushes and Gimp Scripts & Plugins. The plugins on there tend to be, for the most part but not exclusively, single use for example Layer via Copy/Cut. My last quick tip for this post - If you like something by a deviant (term given by deviantArt for a contributor) have a look in their gallery - e.g. Slybug dA gallery (maker of the previous example.

 

I hope you found this useful. In view of the eviction notice that we have all received I will see about shifting this thread to be exclusively on the vault from here on starting with the UI post I mentioned prior to this one.

 

TR

 

               
               

               
            

[Legacy_Tarot Redhand]

               

This is on hold as the vault's editor is being a royal pain in the donkey.

 

TR