Updating tk +quartz failed on Snow Leopard

[Ryan Schmidt]

On Aug 25, 2016, at 11:38 AM, Ryan Schmidt wrote:

> tk isn't the first program to need to deal with Retina displays. Can we find any other program that uses NSWindow's backingScaleFactor selector and see how it handles it?

I missed these warning from the original post:

warning: ‘NSWindow’ may not respond to ‘-backingScaleFactor’
warning: (Messages without a matching method signature
warning: will be assumed to return ‘id’ and accept
warning: ‘...’ as arguments.)

I *think* if we could use the 10.7 SDK, then it would know that -backingScaleFactor actually returns a float and wouldn't complain. But we can't use the 10.7 SDK because it's not in Xcode 3.2.6. Wikipedia says it's in Xcode 4.1 and later, but I don't see it in Xcode 4.1 or 4.2 for Snow Leopard. Maybe it's only in Xcode 4.1 and 4.2 for Lion. (They were different.)

I think that code just has to be excluded for 10.6 and earlier with preprocessor directives. Here's an example of how another project did that:

https://gist.github.com/zwaldowski/3388768

I don't know if those are the correct defines to use.