Do you actually use this much, though? I had to double take because I'm not familiar with the phrase and I'm a native speaker. Typically you might use cool to in this way to describer an action or gerund, or with a prepositional phrase, or as an adverb.
Heck, if anything, I'd say a "cool attitude" is a calm attitude—as in, the person played it cool.
Maybe not that exact phrasing but "he gave me a cool look" can mean exact opposites. Depends entirely on dialect / register. The direct metaphorical version ("he gave me an unfriendly look") is reasonably common in English. The other reading of it isn't so much, but is perfectly understandable (probably incorrectly).
Do you actually use this much, though? I had to double take because I'm not familiar with the phrase and I'm a native speaker. Typically you might use cool to in this way to describer an action or gerund, or with a prepositional phrase, or as an adverb.
Heck, if anything, I'd say a "cool attitude" is a calm attitude—as in, the person played it cool.