Step 1) Import crumbl3d's "Photoshop Resizer Actions" into Photoshop
(Note: These instructions are written using Photoshop CS5. There shouldn't be any major differences between releases, but the odd thing might be in a different place or have a slightly different name if you're using another version of Photoshop.)
- Download BigDave's (should be crumbl3d ...) Photoshop Resizer Actions, then unzip the archive into a convenient folder on your computer.
- In Photoshop, bring up the Actions palette window with Alt-F9, or by selecting it from the "Windows" drop-down menu.
- Click on the button in the very top right corner of the Actions palette window, and select "Load Actions..." from the drop-down menu.
- Navigate to wherever you unzipped the Action files to, then select the Action that describes the size change you want (e.g. to convert a 128x pack to a 64x pack---a 50% reduction---you would want the "Resizer 50% & Transparency Fix.atn" file). Click "Load" to import the Action.
You should see a new folder at the bottom of the Action palette window, with the same name as the action file you just imported. This folder contains two versions of the resizing Action. The only difference between them is how they handle semi-transparent pixels (like those that appear around the edges of images when they're resized). One will make these pixels wholly opaque, while the other will make them wholly transparent (by deleting them). You may want to try both, then decide which one looks best in-game.
At this point, you're ready to use these actions to resize individual files: Simply open the file you want to resize, select the Action from the Action palette window (either the opaque or transparent version), and hit the "Play selection" (triangle) button at the bottom of the window.
However, if you want to apply this action to a large group of files (i.e. every file in a texture pack), keep reading:
Step 2) Resize an Entire Folder of Images
Important: This process will resize
every image file in the folder you select, including images in subfolders (it simply opens each image one-by-one and applies the Action to it, before moving on to the next). So check each folder and temporarily relocate any images that shouldn't be resized (for example, any "placeholder" textures that are simply copies of the standard 16x textures should be pulled out, or they'll be shrunk down as well).
- Make sure the images you want to resize are unzipped and in a convenient folder on your computer. Note that the instructions below will resize these files, so if you want to retain copies of the originals, back them up in a separate location.
- In Photoshop, click "File" --> "Automate" --> "Batch...". A "Batch" window will pop up.
- Configure the "Batch" window that pops up as follows:
- Set: Select the name of the Action you imported (e.g. "Resizer 50% & Transparency Fix")
- Play: Select the version of the Action you want to apply (i.e. either "Making pixels opaque" or "Making pixels transparent")
- Source: Set to "Folder", then click the "Choose" button and navigate to the folder containing the (unzipped) image files you want to resize.
- Ensure the "Override Action 'Open' Commands" box is NOT checked.
- Ensure the "Include All Subfolders", "Suppress File Open..." and "Suppress Color Profile..." boxes ARE checked.
- Destination: Set to "Save and Close".
- Ensure the "Override Action 'Save As' Commands" box IS checked.
- Click "OK", and watch as Photoshop systematically opens every image file in that folder, applies the resize action to it, then saves and closes the file before moving onto the next. Since many texture pack patches contain thousands of image files, this can take a while. (But it's better than doing it manually!)
- When it's finished (finally!), simply zip up those newly-sized image into a standard texture pack .zip archive.Congratulations, you've just resized a whole texture pack!