Tutorial on animated sliders, knobs etc.

**MerryOtter** · 14 December 2005, 05:47 AM

John, I'm not sure I see how limiting the blend to 0-90 is helpful, as the knob is constantly changing size? The poster needs to supply a "strip" of images that the destination application will use like a "flip book" when animating the knobs.

**John Rayner** · 14 December 2005, 10:51 PM

Merry,

If he creates 1 knob, then clones that knob and rotates it 90 degrees. He will have 2 identical knobs. If he then moves the copy away from the original and does a blend between the 2 knobs, he will have multiple copies of the original knob rotated. All he needs to do then is convert the blend to editable shapes and ungroup for many versions of the same knob. If he saves each version of the knob as knob001 through knob360 he can just call any of the knobs easily enough in a program.

**MerryOtter** · 15 December 2005, 11:13 AM

Originally Posted by John Rayner

If he creates 1 knob, then clones that knob and rotates it 90 degrees.... All he needs to do then is convert the blend to editable shapes and ungroup for many versions of the same knob.

As both your image and my image shows, the knobs get smaller in the middle of the blend. Furthermore, if you look closely in the example below, you see that the little "marker" on the knob is not actually being rotated, it's moving along a straight line (and the distance between it and the edge of the knob is changing).

A copy of your image with selected knobs highlighted shows they do not look alike.

He would do better to use the blend tool between two identical, unrotated images, break it into editable shapes, ungroup, and apply the rotation individually. But rotating the ending knob and blending is definitely not an option.

**John Rayner** · 15 December 2005, 12:14 PM

Hi Merry,

I see what you mean about the indicator moving. I could not duplicate the size difference tho. That must be caused by the bevel.

**MerryOtter** · 15 December 2005, 12:38 PM

John, I copied your JPG and drew a line over the last row to show the size difference. The first and last knobs touch the horizontal rule. The middle ones do not. (They are smaller.) I also boxed four of your knobs that look very different from each other.

**Egg Bramhill** · 15 December 2005, 02:41 PM

Another way of doing it is to use Xara3D. Here's one I created using this method. You could make as many frames as you wish this way. The other point is that whilst the knob turns, the light source would remain fixed and not turn with the knob.

egg