Originally Posted by: dvanevenWhen you play a scale is it just a pattern (or box) you play on the neck of your guitar that comes from visual memory or do you first think of the notes that make up the scale prior to playing them or some kind of mix of both?[/quote]
Both. It is visual patterns that I decide to use to make very specific sounds. That is the most important part; music is an auditory art, the patterns, boxes, visual aids, etc. are the tools and devices by which we create musical notes.

Guitarists are typically "visual" players. So are pianists. Contrasting with horn or wind players who cannot visually perceive the musical patterns they make in a graphic manner.

Originally Posted by: dvanevenAnd when you give me the notes then I can play them but not as fast as I can play a scale from pattern/visual memory...[/quote]
This is one reason I practice scales and such: in order to make any one of those an automatic process, to play them on demand, to have them "right at my fingertips when desired".

Originally Posted by: dvaneven
I mean, we guitarists, we can simply transpose our scales by moving our hand up and down the neck of our guitar so we don't have to think too hard, but how does a pianist do it?
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I think you are underestimating how much thought it takes to do this! It's not an effortless process. Once you have it down, it seems easy and not to require much thought. But getting to that point takes thought and effort.

A pianist does it by thought, sight and, or tactile sense.
[QUOTE=dvaneven]When a piano player is asked to play the G# major scale he can't just transpose his C major scale like we do so what does he do?

He knows that all major scales have the same formula. And he has or should have practiced the A-flat major scale enough to shred it out on demand.
[QUOTE=dvaneven]- Does he know how to play each and every major scale (and other scales) from visual memory?

A competent pianist, yes. That is part of the competency test in a university level music degree: piano proficiency; playing all major, minor scales in all keys on demand, playing ii-V-I cadences in all keys, etc.
[QUOTE=dvaneven]
- Does he know by heart the notes to play of that scale and plays them accordingly?