For anyone using GIMP, I spent a couple of days learning script-fu, then Python, then making a plugin in Python to simplify the icon-making process a little. It's not a complete icon maker, due to the nature of icons sometimes having more than one sprite I couldn't really do that, but it does take a number of steps out of the process.
What it does is crops sprites. What you do is first make your foreground colour (in the tool dock) the same as the background colour of your sheet. Then, make a rectangular selection, and make sure the top-left corner is somewhere within the sprite you want to crop. The size of the selection doesn't matter. Then just run the plugin and it'll crop the image to the size of the sprite, with the background colour replaced with transparency.
[SPOILER=Here's a visual tutorial]
First make the foreground colour the sheet's background and make the selection. I also force it to a size of 1x1 so I don't have to actually drag out a rectangle:
![[Image: iRJ9zYDkQfAT2.png]](http://i.minus.com/iRJ9zYDkQfAT2.png)
Run the plugin (I've made Ctrl+I a shortcut to it, that was for Invert Selection by default but I don't use that very often):
![[Image: itkrqlzH4xn2w.png]](http://i.minus.com/itkrqlzH4xn2w.png)
Then wait a moment (should only take a couple of seconds, although it depends on the size of the sprite) and you'll get this:
![[Image: iKVFLAyckmPp8.png]](http://i.minus.com/iKVFLAyckmPp8.png)
The rest is just making it into the icon. You can do this however it suits you but this is how I do it:
[SPOILER]
Ctrl + C to copy, Ctrl+N to make a new 148x125 image (if you switch to a tab with an icon in it first, you won't have to type it in each time), right-click on the default new layer and hit D to delete, then Ctrl+V to paste, and you get this:
![[Image: iuSS8TeobMKPE.png]](http://i.minus.com/iuSS8TeobMKPE.png)
You can transform or move the layer however you need to, or add more sprites (just Ctrl+Z a couple of times in the old tab and you'll get the sprite sheet back).
This sprite is a tad small so I'll go ahead and scale the layer to 200% (interpolation set to None of course):
![[Image: iZ5sQoIm6SACs.png]](http://i.minus.com/iZ5sQoIm6SACs.png)
Then you're done. Export and on to the next one.
[/SPOILER]
[/SPOILER]
Here's the script (I'd add it as an attachment but those still aren't working here). To install it simply place that file into C:\Users\sami\.gimp-2.8\plug-ins (that's for Windows 8, it might differ a bit depending on your OS). This is cross-platform by the way, so it should work for GIMP on Mac and Linux machines as well.
Here's a couple of important things you should note:
What it does is crops sprites. What you do is first make your foreground colour (in the tool dock) the same as the background colour of your sheet. Then, make a rectangular selection, and make sure the top-left corner is somewhere within the sprite you want to crop. The size of the selection doesn't matter. Then just run the plugin and it'll crop the image to the size of the sprite, with the background colour replaced with transparency.
[SPOILER=Here's a visual tutorial]
First make the foreground colour the sheet's background and make the selection. I also force it to a size of 1x1 so I don't have to actually drag out a rectangle:
![[Image: iRJ9zYDkQfAT2.png]](http://i.minus.com/iRJ9zYDkQfAT2.png)
Run the plugin (I've made Ctrl+I a shortcut to it, that was for Invert Selection by default but I don't use that very often):
![[Image: itkrqlzH4xn2w.png]](http://i.minus.com/itkrqlzH4xn2w.png)
Then wait a moment (should only take a couple of seconds, although it depends on the size of the sprite) and you'll get this:
![[Image: iKVFLAyckmPp8.png]](http://i.minus.com/iKVFLAyckmPp8.png)
The rest is just making it into the icon. You can do this however it suits you but this is how I do it:
[SPOILER]
Ctrl + C to copy, Ctrl+N to make a new 148x125 image (if you switch to a tab with an icon in it first, you won't have to type it in each time), right-click on the default new layer and hit D to delete, then Ctrl+V to paste, and you get this:
![[Image: iuSS8TeobMKPE.png]](http://i.minus.com/iuSS8TeobMKPE.png)
You can transform or move the layer however you need to, or add more sprites (just Ctrl+Z a couple of times in the old tab and you'll get the sprite sheet back).
This sprite is a tad small so I'll go ahead and scale the layer to 200% (interpolation set to None of course):
![[Image: iZ5sQoIm6SACs.png]](http://i.minus.com/iZ5sQoIm6SACs.png)
Then you're done. Export and on to the next one.
[/SPOILER]
[/SPOILER]
Here's the script (I'd add it as an attachment but those still aren't working here). To install it simply place that file into C:\Users\sami\.gimp-2.8\plug-ins (that's for Windows 8, it might differ a bit depending on your OS). This is cross-platform by the way, so it should work for GIMP on Mac and Linux machines as well.
Here's a couple of important things you should note:
- This won't work with sheets with transparent backgrounds, unfortunately. However those should be pretty easy anyway, just crop around the sprite, then autocrop the image and you'll have the same result.
- The process will be a bit different for sheets with bounding boxes, although only if the sprite touches the edges of them. For example Slugnoid, you'll have to do it once for the white background, then again for the pink background (this works in the reverse order too, I think).

