Added Fixed Zoom Levels

[cs-mt]

Hi. I made changes so that the zoom-ins and zoom-outs made using the mouse scroll would have fixed percentages between 3% and 500%. It defaults to the previous exponent calculation outside of these levels. These levels are fixed in the code, but this can be made into a setting so that users can have their own fixed sizes.

[sylikc]

Interesting... looks even better now that it's configurable. Give me a few days to run it through the debugger and get this tested. After having messed with zoom so much for the last release I want to see if there's any bugs in the actual zoom portion of the code.

How does it handle it now when the zoom step exceeds the maximum allowed for that image, and it "snaps back" to the % that's currently allowed? Does it try again to zoom to that at the next try?

[cs-mt]

Interesting... looks even better now that it's configurable. Give me a few days to run it through the debugger and get this tested. After having messed with zoom so much for the last release I want to see if there's any bugs in the actual zoom portion of the code.

How does it handle it now when the zoom step exceeds the maximum allowed for that image, and it "snaps back" to the % that's currently allowed? Does it try again to zoom to that at the next try?

If the zoom step is outside of the defined range, it defaults to the exponent calculation.