what´s the best/easiest way to make a head rotate? at the moment, I´m using several 2D images where the head has turned a little to make it look as a rotation movement once it´s animated. I´m just wondering if there is another way of doing it?
This question might sound dumb, but… is there a way of making some images move slower at the same time as other image move at normal speed/faster… at the same framespeed? for example… a cartoon that hit it´s head… the pupils in its eyes start to move in a circular motion in a fast pase while the stars that move around it´s head move much slower.
Bones is an experimental feature currently in development, therefore it’s not exactly easy to use.
Steps to setup a bone based skeleton:
Enable experimental features in Setup dialog, in the Misc tab if you haven’t and estart Synfigstudio so the option takes effect. If you can’t see the option to enable experimental features then your version may not have the skeleton feature. Try downloading the latest stable release (0.64.1) which should have it.
Generate the shape you want to rig with a skeleton. Be sure to add Handles where you want the shape to bend due to skeleton influence. The bones can only work with the handles you added to your shape.
Add a skeleton layer (its under Layer > New Layer > Other > Skeleton in right click menu. if you can’t see it then you may need to repeat step 1). It doesn’t matter where in the layers panel you create the skeleton layer, it’s only really used to access the Bones list
Go into Bone Setup mode (press Alt+7 keys). Synfig should say “Bone Setup Mode” in the Workarea. This mode is used when rigging your character (which is what we’ll do next)
In the Workarea you should see one Handle (unselect all other layers except the Skeleton layer to avoid confusion), this is the root bone that was created when the Skeleton layer was added. If you look closely the Bone handle is actually a combination of 3 Handles: position (green), angle (dark blue), radius (cyan/light blue). For now focus on the position and angle handles.You need to choose the placement of the root bone within your shape. For example if drawing a hand only, then the root could be placed at the wrist. If drawing a complete character it could be placed at the pelvis. It’s your choice though. Adjust the angle handle to match the natural orientation of your shape.
Now for each independent part of your shape you’ll need to add a bone in the Parameters panel. Note that Bones follow a parent/child relationship. You can add bones by right clicking one of the existing bones of the list and selecting “Insert Item (Smart)”. Once you do this you should see (expand the Bones list again) a new item on the list and should say in the value column something like “Bone 2 --> Bone 1”. This means that “Bone 2” (the bone just created) is a child of “Bone 1” (the root bone). The Bone number might be different on your case. You can give the bones a name by expanding their parameters and editing the Name value. You can now create your bone hierarchy by repeating the above process (pay attention to the parent child relationships)
Now that the easy part out of the way ( ) it’s time to rig the shape using Bone Influence valuenodes. Select the shape layer you created at start, in the Parameters panel go to the first vertex (expand the Vertices list). Right click it and select Convert > Bone Influence. Expand the Vertices list again and also expand the vertex you just converted. You should see a Bone Weight List parameter and if you expand it you should see one item on the list, with some random bone as value. If you expand that item you can then edit the Bone parameter (click on the Value column three times, and a selection list should pop up). You can now select one of the bones that were created previously. Which bone to select depends on the proximity of the vertex to the bone. Usually you at least want a vertex to be influenced by it’s nearest bone.
At intermediate bones you probably one each vertex to be influenced by two bones rather than one. You can achieve this by adding a new item into the Bone Weight List. Use “Insert Item (Smart)” right click menu option to do this. Unluckily each time you do this Synfig will reset the Parameters panel, meaning you’ll need to expand the Vertices list, expand the Vertex and expand the Bone Weight List to get back where the bone was added.
If your shape becomes suddenly distorted when adding new bone influences you can correct that by leaving and entering Bone Setup Mode again (Alt+7 twice)
You’ll need to repeat the above process for each individual vertex (yes, it is a long and time consuming process)
Once all the vertices of your shape are rigged then you can exit Bone Setup Mode. Your shape will probably become heavily distorted, do not worry. Look for the position bone handles and move then around a bit. You’ll need to rearrange the handles in order to get your original shape back again (it’s not too hard)
Now your shape is finally rigged! You can play around with the position handle of the root bone and the angle/radius handles of all bones to “pose” your shape as desired. Animation works just as you would expect too.
Phew, that was a bit long. The bone feature still needs more work to make it easier for the user.
And because the above huge wall of text is probably really difficult to follow, I made a video of all the above steps for rigging a simple hand like shape: youtube.com/watch?v=iRBdIW6odI4