I've just made my first usable release of my image viewer. Any comments and opinions are appreciated.
https://github.com/Helios-vmg/Borderless/releases/tag/v0.2.0
I've provided both a Windows installer (x64 only) and detailed instructions for how to build under Linux and BSD. It's pretty thoroughly tested under Windows, since it's the viewer I personally use; I've done basic functionality tests under Lubuntu and PC-BSD.
Important note: the program doesn't have an "open file" dialog. It's intended to work with the file browser. The Windows installer creates the registry entries that add the program to the list of "open with" suggestions for the supported files.
The main raison d'etre of this project is the (IMO) lack of good, free image viewers for Windows. Before starting this project I was using IrfanView, but it was often frustrating. It's been over ten years and it
still displays alpha as a solid color. Other more minor annoyances are: it has a delay of a few seconds when opening an image in a directory with thousands of images because it scans the entire directory in the GUI thread before displaying the image, work that it has to redo if you close the window and open another, or the same, image; it has like six different zoom modes (automatic zooms dependent on the relative sizes of the image and the screen), but not a simple fill (minimum zoom that covers the entire screen).
I've also tried XnView, which does do alpha properly, but I found the UI to be both awkward to use and not at all fluid. Not very friendly to keyboard-only operation, either. I didn't care much for the tabbed interface compared to a multiple window interface, and the UI in general had too much going on, far too intrusive for my taste.
Both programs have a severe case of featuritis, and rather than being content with being the best possible viewers, they want to be mediocre image editors.