🔹 Drivers in Blender<br /><br />A Driver is like a mini script or connection that controls one property using another property.<br /><br />👉 Example:<br /><br />You rotate a bone → another bone’s scale changes automatically.<br /><br />You move a slider → eyelids close automatically.<br /><br />How it works:<br /><br />A Driver connects a target property (what’s being controlled) to a source property (the controller).<br /><br />You can use math, variables, or expressions to define the relationship.<br /><br />Uses in Rigging:<br /><br />Make bones follow or rotate automatically.<br /><br />Eye blink or jaw movement controlled by a single slider.<br /><br />Gears that rotate together (one driver drives the other).<br /><br />🔹 Custom Properties in Blender<br /><br />A Custom Property is a user-defined value you can add to an object, bone, or rig.<br />It’s basically a slider, checkbox, or number you create to help control things.<br /><br />👉 Example:<br /><br />A slider called “Smile” (0–1) that drives facial blend shapes.<br /><br />A toggle (On/Off) for IK/FK switching.<br /><br />A float value for controlling “Muscle bulge” strength.<br /><br />How it works:<br /><br />Add a custom property to a bone/object.<br /><br />Then use a Driver to connect that property to other things (like shape keys, transforms, modifiers).<br /><br />🔹 Drivers + Custom Properties Together<br /><br />This is where Blender rigs get really powerful:<br /><br />You create Custom Properties (sliders, toggles, etc.) → easy controls for animators.<br /><br />Behind the scenes, Drivers connect those properties to actual rig elements.<br /><br />👉 Example:<br /><br />A “Head Tilt” slider (custom property) → driver rotates the head bone.<br /><br />A “Smile” slider → driver activates mouth shape key + cheek bones.<br /><br />IK/FK Switch button → drivers control which system is active.<br /><br />✅ In short:<br /><br />Drivers = rules that automatically control one property with another (automation).<br /><br />Custom Properties = user-made sliders/values that can be used as animator-friendly controls.<br /><br />Together, they make rigs powerful, clean, and animator-friendly
