multiple size icons?

Hiya, I have made a 32x32 icon and attached it as a resource to my BMax game. This is fine if you do view icons in the folder options, and windows also scales it to 16x16 (I guess) for the titlebar and task bar. However, if you do view tiles in the folder options, it gets scaled up and is blocky looking (not sure that anyone actually uses this mode, but they may do...). What is the larger size anyway 50x50 or something? Other icons I've seen appear to be fine at the larger style as if the icon file contains multiple size icons, or maybe they've just used the larger style and it looks OK scaled down.

I'm a bit clueless about this, does anyone have any suggestions? If you can get mutliple sizes in an icon file, how the hell do you do it? I have some BMax code that extracts the icon and uses in the exe and title bar, but if there are multiple icon sizes in the file, how do you tell it which one to use? Also for the .exe it needs to extract more than one so that the different view modes look OK. Maybe I'm talking out my bum here, so any help is appreciated...Thanks

48X48 for large icons I beleive.

If that still looks scaled up, go for 64x64 but thats for those *huge* icons you can have on your desktop normally :)

If you've got Photoshop, you can download a free .ICO exporter plugin that takes care of the formatting and such. 48x48 icons is WinXP max I believe, Vista will allow larger ones.

Actually, XP allows 72x72 icons max, retro. You can mod the registry to enable 128x128, but 72x72 is the normal max.

48x48 is the standard large icon size :)

[edit]

Guys you have a problem with the server. this post appeared twice at exactly the same time. :P (To the second!)

Ah, Cygnus, I didn't know that - but does it help when deploying your application and its big icons on other non-modded machines?

Nah, there's not much use in the 128x128 icons as the target machines need modding too. Unless you do that in the installation!

So stick with 72x72 max size, and 48x48 for large size.

hmm, my desktop ones are only 32x32...

I haev Photoshop SE I could see if that allows the free plugin. Gimp can export as ico with 32-bit colour/transparency but it doesn't say anything about different sizes included in one file. I'm still confused about that...

Yep, they can contain different sizes.
http://en.wikipedia.org/wiki/ICO_(icon_image_file_format)

I use Microangelo Studio for creating/modifying icons and cursors. It has a button on the toolbar for adding a new image to an icon, and you choose among the images in an icon when you want to modify it. When you add a new image to an icon, the standard choices are 48x48, 32x32, and 16x16, or you can create a custom size.

I know I've seen this ability in other icon creation/edit utilities, but don't remember the names. They should be easy to find, though. Probably the freeware sites have some icon editors with this ability.

<edit>
Here are some how-to instructions in a couple of icon editors:
http://www.pcmag.com/article2/0,1895,1158580,00.asp
http://www.rw-designer.com/composed-icons

OK thanks for the extra info guys.