Scroll Wheel zoom behavior logic when zooming close to an object

When I zoom in Rhino it will get all the way up to an object and the zoom function will get more and more sensetive. But then I can point on something else and ‘reset’ the zoom sensitivity to make it zoom into that object.

I simply cannot figure out when the behavior is triggered, I just do it by accident and TF is great.

Can somebody possibly from Mcneel explain how the zoom logic is implemented and how it can be used?

(I have no trouble zooming, and know the tricks I need with zoom selected and stuff like that)

Hi Morten -

What is TF?

I don’t understand the question but perhaps using the Camera command to turn on the camera in one of the viewports and looking at what happens in the other viewports might help.
-wim

Wim’s suggestion to turn on camera points and observe what happens is great [use F6 to toggle camera points].
You will notice all Zoom operations in Rhino are “camera target”-dependent, with target being quite elusive and arbitrary point in the process of constant view navigation. But scroll-wheel zoom and normal zoom basically move the camera closer to the target, with the default Zoom Scale Factor of 0.9 (From Options>View) each scrollwheel roll moves the camera abount 20% closer to the target, but as the distance shrinks, the “precision” of zoom does as well, since it is always ~20% of the remaining distance, hence you end up with super small zoom steps closer to target and it appears to be “stuck”.
The solution may be holding “ALT” with scroll wheel, then instead of moving camera closer to target, both camera and target move by the same factor…

The behavior change, or what you may see as zoom sensitivity adjustment is triggered every time your target point placement changes, which is a result of many different view-related commands in Rhino, like window zoom, zoom selected, etc.

hth,

-jarek