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Aside from the copy and limit transform constraints, the transform constraints also include limit

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distance, maintain volume, and transformation constraints.

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Keep in mind that all constraints and concepts in this video also apply to bone constraints.

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The transformation constraint is the biggest one we should talk about.

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This is a very powerful constraint that helps map certain transformations to affect other

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kinds of transformations.

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For example, in the copy location constraint, we can have the location of one object affect

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the location of another object pretty easily.

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Same with copy rotation and copy scale.

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However, if we wanted to use the location of one object to affect the rotation of another

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object, we wouldn't be able to do it with those constraints.

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These are two different transformation channels.

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However, with the transformation constraint, we can do just that.

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Let's go ahead and add this constraint to our monkey object.

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Now, these settings look a bit intimidating, but it's pretty simple to tinker around with

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once you understand what it does.

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The source section of the constraint settings refers to the target object settings.

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Here you can choose what type of transformation you want to listen to from the target object.

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This includes lock, rot, and scale.

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And the destination section of the constraint settings refers to the constrained object.

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Here you can choose what type of transformation to affect for the constrained object.

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The source to destination mapping section lets you choose which axis of the target object

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affects which axis of the constrained object.

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And the x, y, and z values you see in both sections is for setting a ratio of movement

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between each object.

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This is where the magic happens.

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So let's say very simply that we want every 10 meters of the target object's location

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to drive 90 degrees of the constrained object's rotation.

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We can do this by changing the transformation type in our constraint settings.

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Our source, or target object, is already set to location, so we'll make sure to set our

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destination object to rotation.

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Then we can simply change the max value of the x-axis to 10 meters for the source.

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And to make sure that these 10 meters will rotate the x-axis of the constrained object

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90 degrees, we can change the max value of the x-axis to 90 degrees for the destination.

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And now, as we move our target object along the x-axis, you can see that the constrained

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object is rotating a maximum of 90 degrees.

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Now let's say we wanted to drag our cube further while still affecting our monkey object.

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Well to do that, maybe we can say every 20 meters will rotate the constrained object

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180 degrees, giving us a bit more leeway.

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However, that's not really practical, as we'd have to go on forever multiplying redundantly

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until we're confident the range is what we need.

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No.

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Instead, we can simply keep our 10 meters to 90 degrees ratio and go to the top of our

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constraint to check the extrapolate option.

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This will extend our ratio infinitely and allow us to go past the limits of the min

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and max, but maintain the same ratio of transformation.

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Now if we wanted to have the y-location of the source object affect the x-axis rotation

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of the constrained object, we would just need to change the source to destination mapping

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here.

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Instead of x to x, we can change this first value to y.

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And yes, you can have the same source transformation axis drive to destination transformation axes

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if you like.

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And then we would simply need to change the maximum y-value to complete the ratio.

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This should give you a fundamental understanding of the transformation constraint.

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The limit distance constraint is pretty self-explanatory.

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Similar to the limit location constraint, this constraint takes the input of the user

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to restrict movement of the constrained object.

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However, additionally, it also takes in a target object to use as reference.

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This allows for the user input to set the max distance the constrained object can be

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from the target object at any time.

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In other words, you get to put the object on a leash.

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But you can also invert the effect by changing the clamp region from inside to outside.

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This makes it so that the constrained object cannot come within a certain distance of the

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target object, which makes it feel more like a force field instead.

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And the final clamp region option, On Surface, will force the object to keep the distance

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a constant, not allowing it to get further or closer to the object than the distance set.

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The maintain volume constraint prevents objects from freely changing their scale.

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Typically, when scaling an object, the volume of your object gets increased for free.

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However, with maintain volume, it restricts you from gaining free volume, forcing your

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object to bend and contract while scaling, just like a real volume would if forced to

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change size.

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However, the volume input value is a world value.

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Therefore, you'll need to know the neutral volume of your mesh.

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I hope this helps you understand more of how the transform constraints work.

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Feel free to experiment or read more about them in the documentation in the description

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down below.