GIMP Script: Scale Pattern

Someone on GimpTalk was complaining that patterns weren't scalable so I though of a work-around.

I just wrote a script to take the current pattern, scale it and leave a copy in the clipboard. Gimp 2.6 lets you use the image in the clipboard as a fill pattern, so you can just use it from there.

You can scale from 20% to 500%

It uses Lanczos scaling working with a tiled copy of the image, so if a pattern is tileable the scaled one will be as well.

You can access the script by right clicking on a pattern and selecting "Scale Pattern..."

-Rob A>

More cool stuff from the GIMP-master.

Thank you so Roba!

Isnt it limited to 512x512 if you use the clipboard?

At least I got those problems while using it :(

Quote:

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Originally Posted by Sagenlicht

Isnt it limited to 512x512 if you use the clipboard?

At least I got those problems while using it :(

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Correct - the clipboard is limited to 512x512

I hadn't noticed that because I rarely use patterns that large. Should I cap the size at 512x512?

Alternately, I could add an option to save it out as a pattern and then refresh the pattern list...

-Rob A>

I actually run into that limitation quite often, I hoped that it would be setable in the options but couldnt find it.

Saving it as a file would be an option I think. That is what I actually do atm. I created a tmp folder in my gurm directory and copy any patterns I created for temporary use there.

My textures are mostly 500x500, they rarely show tiling. 512x512 should fit everyones needs.. Except those of you who do real super res maps...

This whole question of scaling and resolution has me a little confused. Example: For a custom map in a FPS game, I have a 3D heightmap I created in PnP that's 2048 x 2048 px, representing a 2 km square area. Now I'm making the 2048 x 2048 texture map in gimp. I'm using cg textures (made into seamless tiles) as patterns and bucket-filling them to each appropriate layer (e.g., grass, forest floor, water), and adding layer masks, then erasing and using whatever tricks of the trade to let the textures show and merge smoothly. OK, these texture tiles were 512 x 512, but the patterns looked too huge and ungainly for everything except rock. So now I'm working with mostly 64 x 64 px tiles, which seem to be working better. But is there an ideal scale of a tile that corresponds to this scale of terrain? What would it be? Also, is there a way to just swap out a pattern on a layer, without deleting the layer or affecting the layer mask? When I apply a new pattern in bucket fill to an existing layer that has a pattern on it, the fill just adds and mixes the two patterns, rather than replacing the original.

Check the "Entire Selection" radio button in the fill options; that'll stop it from mixing them together. For the rest, I'll let someone more knowledgable than me answer :)

The ideal size of a texture tile varies based on a few variables:

• The size of the object it's texturing—A small object will likely need a much smaller texture map than a large one, all else being equal.
• The relative scale of the texture detail to that object—Blades of grass are much smaller than bricks, so the texture needs to be scaled such that its details are the right size, regardless of the actual resulting size of the texture map.
• How much area the texture will have to tile over—The smaller the texture, the more obvious the tiling will be.
• How much memory footprint is permitted—This doesn't really affect what you're doing, since you're laying a large texture over a sizable piece of terrain, and it's likely not spatially compressed, but usually there is a strict memory budget for textures in a video game. A smaller texture that tiles is often better than a large one that doesn't, even though the large texture looks nicer.
• How close the viewer/camera gets to the textured object. If an object isn't likely to be seen close up, use a lower resolution texture.

There really isn't a hard and fast rule, other than if it looks right, it is right. And even that one is tempered by the technical requirements of the work.