Rapid SDK provides a simple one-button workflow to quickly set up
driving relationships between one or more properties. It’s aimed to help
simplify the steps needed to adjust particular relative values or even
non-linear behavior.

Obviously a one-button solution has limitations such as defining more
complex driving setups (multiple driving objects) or evaluating certain
properties such as colors or strings. But this is beyond the scope of
this add-on.

The video contains various chapters for easy access and more in-depth information. See the video chapters section below.

Important Note:

The add-on is still in it’s testing phase and it’s possible that certain object and property combinations are not yet functional or supported.
If you hit a limitation or issue feel free to contact us. We’ll see what we can do.

Basic Overview: 0:28 min
SDK Fundamentals: 1:41 min
Intermediate Example: 4:11 min
Preferences: 8:44 min
Shape Keys and Bones: 9:58 min

  1. Download the add-on as a ZIP-file.
  2. Open the Blender Preferences window by choosing Edit > Preferences…
  3. Select the Add-ons tab.
  4. Press Install… and select the downloaded ZIP file.¬†After successful installation the add-on should be visible in the list.
  5. Activate the add-on.

For a one-button workflow to work a basic selection and workflow scheme needs to be followed.

Rapid SDK is based on an initial selection which defines driver and driven objects. Since there is no selection order in Blender but everything is based on an active object and an additional selection the system defines the selection rule: The active object is the driver and all other selected object are defined being driven.

Because of this requirement it’s currently not possible to have more than one driver object during the setup.

When setting up a driven key relationship the general procedure is to first define the starting values and, after storing these, to then define the end values of the range. Using a predefined range of motion (ROM) by having a temporary animation on the driver is a common practice and helps going back to specific values to further refine the relationship.

With these fundamentals it’s easy for Rapid SDK to identify what the driving and driven properties are; everything which changed between the start and end of the defined range will be a part of the created driver. If more than one property changed on the driver the sum of these values will be used as the driving value. If one or more properties changed on the driven object the driver will affect these individually.

To edit an existing driver only one object may be active. Again, this is a limitation by the selection system of Blender.

When going into Edit mode only driven properties are being recorded and evaluated for editing. Any animated properties are skipped. All driving curves of driven properties will be muted. This allows the user to change the current values. Either on the start or end point of the driven range or at any point in between, for example to adjust the linearity of the relationship.

After editing the driven value and leaving Edit mode either existing driven keypoints are updated or a new keypoint is created. Any previously muted driver curves are set back to active.

These simple steps allow Rapid SDK to evaluate and choose the current mode based on the selection and furthermore take only the changing properties into consideration. Therefore it’s necessary to setup more complex relationships in a one-by-one fashion to guarantee that only the right properties are considered for the setup.

The Rapid SDK menu item is located in:

Object Mode: Main Menu > Object > Animation > Rapid SDK

Pose Mode: Main Menu > Pose > Animation > Rapid SDK

Rapid SDK is designed to be used on two modes: Creating a driving relationship and editing an existing driver. The current selection defines which mode is being used.

Create Mode

  1. Select two or more objects. The last and currently active object acts as the driver. The state of the selected objects defines the starting point of the relationship.
  2. Run Rapid SDK. This stores the current values. All properties which are not already driven or animated but change over the course of the setup will be part of the relationship.
  3. Select the driver and modify it to define the end range of the relationship.
  4. Select the driven object or objects and adjust these accordingly.
  5. Run Rapid SDK again to finally setup the driver.

Edit Mode

In contrast to the create mode only one driven object can be edited at a time. This is a current limitation due to the one-button design of the add-on.

  1. Go to the position where the driven object needs adjustment.
  2. Run Rapid SDK. This temporarily disables the drivers so that the object can be manipulated.
  3. Adjust the properties of the driven object.
  4. Run Rapid SDK again. This either creates a new keyframe on the driving curve in case the driving value has changed as well or existing keyframes on the driver curve will be updated. Also, the driver curves will get activated again.

If the selection changes while in Edit mode and Rapid SDK is run the driver curves of the previous object will be activated and the new object will be put into edit mode.

  1. When editing a relationship only one object can be selected.
  2. Supported properties for the auto-detection of changed values are the default properties location, rotation and scale. Also any number based custom properties and shape keys for meshes and curves. Not included are non-mesh properties (i.e. lights) as well as modifiers.