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I'm trying to create animated cutaway views on multiple objects in my scene. For example, in my car model, the seats and other interior objects are separate objects.
This question talks about using an animated bisecting technique. However, it involves adding a solidify and boolean modifier to every object.
Is there an easier solution?
Solidify and boolean modifiers should work fine.
You can use CtrlL to copy modifiers from the active object to the selected objects:
Add the solidify and boolean modifiers to one object.
Select other objects you want to bisect, keeping the object with the modifiers active (last selected).
Press CtrlL> Modifiers
By creating a node group like this:
By changing the bottom value input on the greater than node, you can adjust where the bisection takes place.
By default it will use the local coordinates of the object, but if you want to use global coordinates you can use a vector transform node, however 0,0,0 will still be at the object origin (see bottom example for using global origin):
To control this for multiple materials at once, add the node group to the end of the node tree:
If you want to use global coordinates with 0,0,0 at the world center, use the Position output of the geometry node instead:
This probably works better with multiple objects.
Section Plains tool. youtube.com/watch?v=ZiMA1IAn8HU
$\endgroup$
Alt+C > Convert to mesh. There is also a tool for drawing cross sections of objects in the viewport, called Clipping Border (Alt+B).
$\endgroup$
One possibility is to animate the Camera Clipping Start Distance.
In Blender, the clipping distance defines the area of the scene that is visible to the camera. So, for example, in this instance shown here, everything in the scene between 0.001 distance units and 5.0 units from the camera is visible to the camera, and anything beyond 5 will be clipped out of view (i.e. not visible):
NOTE: You can toggle the clipping distance indicator's visibility on & off here:
Camera Object properties window -> Camera tab -> Display section -> toggle Limits
These Start and End values/distances can be changed so that part of your car (and any other objects in the scene) will not be visible to the camera. For example, you can increase the Start clipping distance to be halfway into your car, like this:
NOTE: This model of the car is not one mesh, but many separate meshes, so any objects in your scene will get clipped from view. In addition, object modifiers are not effected in any way by camera clipping.
In addition, the Start and End values can be animated:
Set the green frame cursor to the beginning of the animation time. Here, it is set to frame 1:
Now position the mouse cursor over the Camera Clipping Start value and press I to set a keyframe:
You should now see there is a yellow line at frame 1 indicating a keyframe is set there.
Now do the following:
Position the frame cursor at the end of your animation
Increase the Clipping Start value so enough of your car is not visible
Position the mouse cursor over the Camera Clipping Start value and press I again to set a keyframe
Now if you play your animation, or render your animation, you will see the car and any other objects in the scene get cut in half:
Unfortunately, there are at least 2 limitations of this technique that might make it unsuitable for your purposes:
This technique is very easy to animate if your camera is stationary during the clipping animation, but if you start to move the camera around, the clipping distance will still effect the scene, so it may be more difficult to control exactly how much of the car is visible and how much is clipped:
Since the clipping of the car's visibility is based on distance from the camera itself, you will only be able to hide parts of the car directly facing the camera. So, you will only be able to use this technique to render 1 of the 4 views you showed in your question:
I changed gandalf3's answer slightly to over come a few problems. First, it does not work on arrays with dupli verts,and it also does not work on any type of curve object.
I just changed the texture input type to Camera. That allows a nice whole scene cutting effect (on any and every object). The mapping node is just to translate and rotate the slice.
Also if the color on the Transparent node is above pure white, then there is a nice semi-transparent cut.
