Metro UI Theme for Archivers (Dev notes)

• For simple icon editing used Pixelformer (old but functional and quite light-weight).

Filetype

• Filetype icon used in the original Dubaku's WinRAR theme appears to be a modified form of Dakirby309's Live, mail icon. Similar icons (1), (2) with more permissive licenses are available.
• As Dubaku's theme, included only one filletype icon for all Windows filetype associations with WinRAR, additional icons for the rest of 7-Zip's filetype associations had to be created. For this purpose, vector representation of Dakirby309's original icon was used and modifications were made for the end-result to remain as similar to Dubaku's version as possible.
• Due to the comparatively huge size (564KB) for the filetype icon used by Dubaku, some of the image sizes in the .ico file were removed. This is done in Pixelformer, simply by opening the .ico file and deleting the undesired image sizes from the Project menu on the top-right.
• The image sizes included in the icon files were 256, 128, 64, 48, 32, 24, and 16 pixels. The sizes were decided using references from Which icon sizes should my Windows application's icon include? and Windows Icon Reference Chart.
• As since Windows8, .iso files can simply be opened through Windows/File Explorer without the need of any virtual drive or extraction software, users have usually let File Explorer handle .iso files. For this reason, to circumvent the default behaviour of 7-Zip Theme Manager to associate an icon with .iso extension too, the default File Explorer icon for .iso files was included in the theme. The same approach appears to have been used in 7-Zip Filetype Theme - Windows 10. Standard Microsoft icons are apparently allowed such reuse.
  • The location for the .iso File Explorer icon was found through the Registry Editor (HKEY_CLASSES_ROOT > Windows.IsoFile > DefaultIcon) to be %SystemRoot%\System32\imageres.dll,-5205 (i.e. in file, C:\Windows\System32\imageres.dll with icon ID 5205). A utility like IconsExtract can be used to extract desired icons from a .dll file.
• Image preview.jpg (430x280px) and Metro-UI-Theme-for-Archivers-Filetype-Icons.png (used in README.md) were made, based on their counterparts from previously mentioned, 7-Zip Filetype Theme - Windows 10.
• Additional filetype icons were made for Zipware.
• PeaZip used individual icons for groups of filetypes. Therefore, additional filetype icons were made based on PeaZip's default icons which employed module, kcmdf icon (for PeaZip_block.ico) and Document-save (for PeaZip_package.ico) icons. Couldn't find the exact "cd" icon used for PeaZip_cd.ico, so employed the similar iso icon instead. Created separate folder for PeaZip in the project for easier implementation.

Toolbar

• Steps for converting original icons into desired size icons for 7-Zip through Pixelformer:
  • Open the .bmp icon (import OR drag & drop).
  • Change image size as required from the Image properties menu (Image > Properties).
  • Copy the size-changed image (Ctrl+A > Ctrl+C), no need to save this modified file.
  • Create New project (Ctrl+N), select or enter the desired size of the new image. From the section Target color format, select RGB color with alpha channel (32 bpp); "alpha channel" represents transparency.
• Since Dubaku's theme didn't include icons for Copy and Delete, these had to be created. Icons appbar.page.copy.svg, folder-move, arrow-right, box-remove, and copy were used for this purpose. A couple of alternate icons were also included.
• Image preview.jpg (430x280px) was also created, through simple 7-Zip Window screenshots with Spectral Oils background.
• Additionally, converting from .png to .jpg through MS Paint and CoffeeCup PixConverter resulted in a visibly lower quality image. Using Gimp 2.8.22, however, the .jpg image showed little to no visible quality depreciation (exported image as .jpg with default settings aside from Quality increased to 100).

Issues

• In the beginning, when 7-Zip Theme Manager was used to change icons, although, the toolbar icons got updated, filetype icons didn't. Attempted various solutions, restarted, ran 7zTM as administrator, tried (recommended on one site) an older version (9.2, for which even toolbar icons didn't change), both 32 bit & 64 bit versions of 7-Zip, even a third-party theme (first downloaded through its reuse on a GitHub project as there was some issue at DevianArt) which was claimed to be working with 7-Zip 15.05. Finally saw the comment advising to reset file associations which resolved the issue.
  • To resolve this issue, open 7-Zip > Tools > Options... > System > click on + twice > Apply
• Using Gimp 2.8.22, even after spending much time I was unable to deploy transparent background for the .bmp toolbar icons. Even tried with importing .bmp into Inkscape, exporting into .png and then converting back into .bmp through Gimp. Was also unsuccessful when tried with Gimp 2.8.0. Probably kept missing some setting.
  • While exporting to .bmp, had to keep checked Compatibility Options > Do not write color space information, otherwise the icon wouldn't even show on 7-Zip's toolbar. An odd behaviour observed for the result of using 7-Zip Theme Manager on such .bmp icons was that the problematic icon gets replaced by the next icon on the toolbar (causing some confusion when debugging).
• Using ArtIcons, I was finally able to get transparent background to show correctly. As it is not free, used a year 2009 software, Pixelformer.
• Couldn't get 7-Zip Theme Manager's "Change SFX Icon" feature to work. However, an icon similar to Dubaku's SFX icon has, nevertheless, been included in the filetype/Metro UI folder. Icon should still be changeable through Resource Hacker though.
• For 7-Zip, due to unknown reasons, the icon for .squashfs filetype also doesn't change.