This will be a two part tutorial. In Part 1, you will be creating:



A simple spinning circle.

Many thanks to ClayOgre for pointing out the need to begin with a larger image and then scale it down to get the final animation shown above. Originally, I started with a smaller base image, and the resulting animation was both oscillating and rotating, which was not the intended result.



From the main gimp window select:

File | New and create a new image with dimensions 1200px width and 1200px height

Then create a New Transparent Layer either from the Layers dialog window or by selecting:

Layer | New Layer



Click OK in the New Layer window that opens.

Select the Ellipse Selection Tool and from the Ellipse Select dialog window set your ellipse selection to a Fixed Size of 600px Width and 600px Height.



Drag a Guide from the ruler on the left side of your image to the 600px mark on the top ruler (which is the middle of your image). Follow that by dragging a Guide from the ruler at the top of your image down to the 600px mark on the left side ruler. Alternately, you can also set up Guides by selecting:

Image | Guides | New Guide and set a Guide in the Horizontal direction at 600px



Press OK

Follow that by again selecting:

Image | Guides | New Guide

Then choosing a value of 600 but select Vertical for the direction from the drop down box:



Click OK. Your image now has a vertical and a horizontal guide interesecting at the center of the image:



Make sure that your New Layer is selected in the Layers dialog window.

With your Ellipse Select tool selected, click on your image window at the point where the guide lines intersect, but do not move your mouse yet. After clicking on that spot, hold down your mouse button and then press CTRL-SHIFT together then drag your mouse outward and you will get a circle selection that is nicely centered in your image window. Then you can release the CTRL-SHIFT keys and your mouse button.


Centering objects in their respective image window is very important for positioning them on the new background for your animation.




Select a Foreground Color of 1427ba (blue color) and fill the selection. If we were to rotate this plain blue circle, it would appear to just stand still. So we will make half of it lighter blue so we can observe the rotation.

With your selection still active select the Rectangle Selection Tool:



Set your Rectangle Select tool to Subtract from the Current Selection:



Start your Rectangle Selection near the top left corner of the image and drag it down towards the lower left corner of the image and then over to the Vertical Guide at 600. This will divide the circular selection in half:



I have placed a letter A in the image above to show which side of the circle will remain selected after the Rectangle Select tool was used.

Fill that selection with a lighter blue color 16cae6. Then do:

Select | None

Remove your Guides either by clicking on the Move tool and selecting each guide and moving them back to their respective rulers, or select:

Image | Guides | Remove all Guides

This is what our image will look like:



So we now have a nice centered circle on it's own layer.

From the main gimp window select:

File | New

Again make a 1200x1200px image.

In the new image window just created, select:

File | Save As

And save this image in a new working folder with the name background_000001.xcf

In background_000001.xcf select:

Video | Duplicate Frames



We are making a 30 frame animation. We already have one frame, background_000001.xcf. We need 29 more so therefore set N times to 29 then click OK.

Then select:

Video | Move Path



In the window that opens check the Instant Apply box (A).
For Source Image/Layer (B) select your blue circle layer from the drop down menu if it is not selected. Do not worry if the full name of your Source Image/Layer is not the same as mine. As long as you have the correct layer selected. (Just click the little arrow to at the right side of the red-outlined box shown above to select your New Layer layer if necessary.)
Stepmode (C) set to None.
Handle (D) set to Center
For the X and Y values (E) set X to 600 and Y to 600 (which is the center of the background_000001.xcf image)



In GAP, to animate an object, you use Points, which are basically keyframes. When you start GAP, you are at Point 1. The first point in your animation. We sat up the first Point of our animation making our initial settings. Now to rotate our circle, we must add a point and then change the value of the Rotate section.

Click Add Point (F)

Change the Rotate (G) value to 360.0 either by moving slider all the way to the right, or typing in the value in the appropriate box shown above, or using the little triangular up button and hold it down until you reach a value of 360.0 for the rotation. As an exercise, if you continue to press the little triangle up botton, you can go beyond a value of 360.0. In this tutorial, we will just rotate our object once.

Once you have set the Rotate value press AnimPreview (H):



Select Exact Object on Frames as shown above and then press OK.

This will make a preview for you to watch your animation. When finished viewing the preview, close it out and also close the image that gets created and select Don't Save.

Return to the Move Path window and press OK.

When that proces is finished select:

Video | Frames to Image



Set the To Frame, as indicated in the image above to 29 instead of the default 30. If you recall in the preview window that you made, the animation stopped briefly each time it went around. The reason is that frames 1 and 30 are identical. In frame 1, the circle is rotated zero degrees and in frame 30 it is rotated 360 degrees, which is the same as zero degrees rotation. Since the two frames are identical, this shows up as a pause in the object rotation. By deleting one frame, we can have a continual rotating object.
Then accept the other default values in the window and click OK.

In the new window that opens, select:

Image | Scale Image



Choose a value of 300px for both the Width and the Height values. For Interpolation method choose Cubic (Best)

Press Scale

Note: The reason that we do not start out with an image 300x300px is because apparently due to the way GIMP interpolates an objects placement when it is rotated, the resultant animation would be not be quite smooth. A huge thanks to ClayOgre for pointing this out, since the original tutorial started out at 300x300px and it produced an animation that kept sort of vibrating as it rotated.

Then do:

Filters | Animation | Optimize (for GIF)

When that finishes processing, another window opens. In this window select:

File | Save As

I chose rotate.gif for the filename.

Press Save

Another window opens:



Select Save As Animation as shown above the click on the Export button.

In the window that opens after that, just press the OK button.

Your animated gif has been created.

Please continue to Part 2 if you would like to do more.

nice tut,seems a lil bumpy tho

In Part 2 we will be making this:



Return to your background_000001.xcf window. Select:

Video | Frames Layer Delete



Accept the default values in this case and press OK.

This removes the circle layer that we added in Part 1 and allows us to re-use those frames to make our second animation.

Select:

Video | Move Path



Just as before, check the Instant Apply box (A). For Source Image/Layer (B) select the same New Layer blue circle. For Stepmode (C) select None. Handle (D) set to Center. X and Y values (E) are X:600 Y:600.



Click AddPoint (F)
Set the Rotate (G) value to 180.0 This will cause our circle to rotate forward 180 degrees.



To make our animation rotate from 180 degrees back to zero degrees we need to add another point (keyframe) to our animation.

Click the AddPoint Button (H)

Set the Rotate value (I) back to 0.0

Side Exercise for the Curious:

If you look in the window just above the X and Y values, it shows:

Current Point: [3] of [3]. That lets you know that you are viewing point 3 out of 3 in your animation. (You start out at point 1, you added point two to rotate the circle 180 degrees and then you added the third point and rotated the box back to zero degrees) You can review and change the values for points in an animation by selecting from the Prev Point, Next Point, First Point, and LastPoint buttons. Try clicking them briefly as an exercise. In this case, the Rotate values will change as you move from Point to Point.

Click on the AnimPreview button.



Again as above, in the window that opens select:

Exact Object on Frames then click OK.

A little preview will be created. Play the preview, then close it out as well as the image that gets created and choose Don't Save.

Return to the Move Path window and click OK.

When that finishes processing, select:

Video | Frames To Image



Again, if you noticed in the preview of the animation that played, there was a small delay in the animation caused by frames one and thirty being the same (both are set at a Rotate value of zero degrees). If you want the animation to play without the delay, set your To Frame to 29 (thus eliminating frame 30) as shown here. For some cyclic animations such as rotating objects, you will need to remove a frame from an animation to get it to cycle without delays.

Click OK.

A new image window gets created, from that window select:

Image | Scale Image



Just as in Part1 make the Width and Height 300px. For Interpolation choose Cubic (Best)

Press Scale

Then do:

Filters | Animation | Optimize (for GIF)

Yet another new image gets created. From that window select:

File | Save As

I chose rotate2.gif then click Save.



In the window that opens select Save as Animation then click the Export button.

Another window pops up, accept the defaults and press OK. Your animation has been saved.

Mike1946, yes it is bumpy and I believe this may be a GAP issue, since I have experienced this when rotating other objects with GAP. If someone else has a remedy that they use to keep object rotation smoother when using GAP please indicate it here or PM me and I will adjust the tutorial. Thank you.

Edit: Thanks to ClayOgre for pointing out that I needed to start with a much images and then scale them down to get a decent looking rotation animation. The original attempt here resulted in animated images that both rotated and oscillated at the same time. Thanks again ClayOgre for pointing that out. :h:

The oscillation of the rotating image is more of a GIMP problem than a GAP problem. If you rotate a layer by 360 degrees, you will notice that the layer changes size; resulting in a different center point. This slight movement of the center point is present throughout the rotation, not just at 360 degrees. The GAP is basing the location of the object on its rotated center and since this is changing, the GAP's positioning is changing. It should be possible to fix the problem but it will probably require a change to the GIMP's rotation tool, not the GAP (although the GAP code could probably be improved a little).

OOPS!!

This is really funny.. Don't know how i got it, but....

Hi

I don't even know where to begin. some1 PLZ help. i can't the Help to work to help either. i find instructions hard to follow cuz of understanding/ reading. I'm trying 2 make layerd background regular page size.kinda of like page over page over page but still being able to see the different layrs. Do you understand? I hope so.

thx
Shy

Since when I made the thing the whole screen was blue already it only came out as a half circle

Wyvern that makes sense if you started out with a background the same color as one of the halves of the rotating circle. If you want to see the whole rotating circle, you will need to use a background color that is not the same color as either half of the circle. Thanks for trying the tutorial. :h:

In part 1, after you save the second layer (background_000001) it says Video | Duplicate Frames

Where is Video? People have told me it's next to Script-Fu, but it's not there? Anyone know where it is?

you must download gap first

And this is the result I got, trying to imitate kb3llm's image :l:
[img]file:http://www.flickr.com/photos/8242768@N06/492497565[/img]

Thanks for the tutorial :h:

Although i do not fully understand it :l:

this was my first gap tut! =]

Great GAP tut. Thanks.

chaotikhell and zuluboy thanks to you and anyone else who recently tried out the tutorial. Hope it helped you to begin to understand and enjoy using GAP. :h:

[img]http://drivemeinsane.com/submitpics/1162721830metroid-prime-multiplayer-ch.jpg
[/img]

nice tutorial

i tried it and it didnt work out to well :s:

why ?

Where do I download GAP? :a:

check the news board there you get the link, is a recent post so will be almost on top

:s: Hi I'm ok with gimp but i need help.(sorry for wrong section in forum and i could probably find this)butttt, I need help with the tools. One time i downloaded gimp and then i some how made the options for tools go away D: idk how to get it bak now! (im talkin bout the bottom part of the main gimp tools thing) it says "you can drop dockable dialogs here" WTF!? LOL plz help if u no wat i mean if u dont ask me or suomething

Great Tut.

I came a bit late to this tutorial. I really wanted to be able to rotate an image and this tut is perfect. My wheel ding is not regular. I started out with one that was 300x299 cropped but went ahead with it. The wheel wobbles just a little because it's just not quite round - 1 pixel off in ht. This is it after shrinking to half size.

Thanks for the great tut! It's clear and easy to follow.