Animation problem

Hello,

If this problem has already been asked, I’m sorry.

I am new to Blender but know quite some things already :wink:

One problem I am having is while animating with key-frames, sometimes if for example I have a search-light moving over the ground, and then I have a moving camera,

When I move the camera and make some new frames, the lamp starts moving strangely around the screen…

If you don’t know what I mean I will try to explain it better, thanks

SeBsZ

yes, a better explanation would be good to understand your problem… the only association i have when i hear “strange movement”, is, apart from “strange animation” the fact that IPO curves tend to “distort” movement if keyframes are placed too closed together AND the values are far apart. to check that, change any 3D view to an IPO view (SHIFT+F6) and select the object you’d like to inspect. you can select individual curves (locX, locY etc.) and enter edit mode, much like object edit mode, with TAB. here you can select and manippulate individual points (keyframes) and change their value and position in time. some useful shortcuts:
SHIFT + S >> Horizontal flattens your tangents; V, H change the incoming/outgoing interpolation to corner, bezier corner or bezier smooth (multiple H). experiment a little.

hope that helps, if not at least you may have learned something new abt. the IPO window :slight_smile:

Thank you for the reply,

With strange movements I meant an object increasing in size and it going up and down…

I have a light, spot light, that I have rotating so the ‘halo’ thing moves across the ground. You understand what I mean. Although I only added rotate animations, it suddenly moves up and down, the whole lamp, and it is scaled and it increases in size, all those funny things.

What i think is causing the problem, is that when i press ‘i’ to insert a key frame, i always choose rotate/scale/position, you know the one that has it all in one? Well… i didn’t know what the difference was between that option and one of the others… why pick “location” if I can choose the combination one…

Maybe you guys could give me some advice on that.

Thanks,

SeBsZ

It might help a lot to switch to the Animation screen. (The pulldown that says “SCR 2: Model” has four or more other choices.) This shows you the IPO-curve window and other windows in a convenient arrangement for seeing what’s really going on.

As I presume you know, an IPO is simply a curve, whose horizontal axis is time and whose vertical axis is the value of some variable … such as “Position X,” Y and Z; Sizes; Rotations; and so-forth. When executing an animation, Blender uses these curves to determine the actual value settings, frame by frame.

When you “set a keyframe,” what you’re actually doing is establishing a new set of explicit points on various IPO-curves. The in-between (“tween”) points are computed by interpolation along the curve between these points. You can edit these curves in the same way that you can edit a Bezier curve in an ordinary model: IPOs are such curves.

I believe that when you look at the actual IPOs for your lights, you’ll see that your subsequent edits have changed those curves from their original values.

It is also possible … that your lights are rotating around the wrong point. In general, the point around which any object rotates is quite adjustable.

Ah right…!

Is it possible to endlessly repeat a certain animation? For example a search-light searching the ground, have it repeat all the time… ?

SeBsZ

In the IPO window (e.g. Screen #1), select a curve, then click on the Curve menu. There are two important items here: the Extend Mode and the Interpolation Mode.

Change the Extend-Mode to Cyclic, and the animation for that curve will repeat endlessly. You’ll see the effect immediately in the curve-window.

The Interpolation-Mode is also useful. Right now you’ll notice that there’s a discrete point on the curve for each keyframe, and that in-between those points the curve is bending smoothly. If you change it to “Linear,” you’ll notice that now the curve goes straight from one point to the next.