Alpha Blended Toolbar Images on XP+

I wanted the next release of PN to have some nicer icons, as the roughness of the toolbar images was jarring. The best way to get good looking smooth images on a toolbar is to use images with an alpha channel. Unfortunately this is only supported in XP and up, but I think it’s a worthwhile change for users on those platforms.

PN Alpha Blended Toolbar

It took me a long time to find a good way to produce bitmaps in the correct format for windows to handle the alpha. The bitmaps must be stored as 32-bit where 24 bits are used for the colours and 8 bits for the alpha channel. Very few tools seem to support this format. So here are two methods you can use:

Believe it or not, use MS Paint

First create your image using a good transparency aware design tool like Photoshop or The Gimp. Now save your image as a PNG with transparency. Next, load the PNG into MS Paint and immediately save the file as a bitmap. If you look at the bitmap in a normal editor now you will see a black background but this is caused by the alpha channel. MS Paint claims it’s only a 24-bit bitmap but it truly is 32-bit with alpha.

Alternatively, use a handy tool!

I spent a long time looking for utilities to do this and was beginning to think I’d have to do it myself when I stumbled across AlphaConv by Adam Najmanowicz. This useful tool will transform between .png, .tga and .bmp formats keeping the alpha channel.

Nice Icons

You may recognise the glyphs in the above toolbar as coming from the Silk icon set from famfamfam.com. This excellent set is free, and my thanks to the designer for making PN a prettier piece of software!

At the moment the PN development builds only support the toolbars properly on XP. I have yet to work out the best way to continue using older icons for older OS versions.