What is resolution independence?

[Scottyfrombi]

I keep hearing this mentioned, but I am not sure exactly what it means in practical terms. Does it allow you to view a larger aspect ratio than the hardware allows? Does it shrink or expand stuff other than fonts as the fonts are expanded or contracted to make more of the image appear on your screen?

Can someone explain resolution independence or possible link to an explanation even better with some sort of examples of it.

Thanks

 

[nikiski]

Well, simply put, resolution independence means that measurements in computer is being measured in human units (examples: inches, meters) instead of computer units (pixels).

Say for two 15.4" screens that have 1680 x 1050 and 1440 x 900 as their resolutions respectively (call them A and B). A font that is 12 pixel high will display much smaller in size in screen A in comparison with screen B. (In the same area of 15.4" diagonal, screen A has more pixels than screen B, which means screen A has a higher pixel density (more pixels in a fixed size unit, for example, pixels per inch(squared))

With resolution independence, developers can draw and print according to human units. Say if a developer wants to draw a 5 point wide line, 1.5 inch in length and 1 inch from the top of the screen, the line will look identical on both screen (size and position wise) while having different pixel coordinates.

This allows for higher pixel density screens without compromising readability.

An wikipedia article is available at http://en.wikipedia.org/wiki/Resolution_independence

 

[Scottyfrombi]

Excellent. Thank you for taking the time to explain so thoroughly. The question now remains, in the real world present or near future, will a 15.4" with Leopard in a MBP be able to view images from say a web page or image viewer in 1680 x 1050 for example or will a 23" cinema screen be able to see the same resolution as a 30" within it's borders, (albeit a much smaller representation)?

 

[Sesshi]

Excellent. Thank you for taking the time to explain so thoroughly. The question now remains, in the real world present or near future, will a 15.4" with Leopard in a MBP be able to view images from say a web page or image viewer in 1680 x 1050 for example or will a 23" cinema screen be able to see the same resolution as a 30" within it's borders, (albeit a much smaller representation)?

I think you might have it the other way around. The point of resolution independence is to make what you see on the screen independent of the resolution of the screen. If you're trying to look at a 4" x 6" picture onscreen, with RI it will show up as 4" x 6" on your screen regardless of it's resolution. If you are trying to look at a 1680 x 1050 image at 1:1 pixel ratio on a 15" MBP screen, it will still go off the screen.