Skinning Sample

Category: Visuals

Min PC GPU: Fermi-based (GTX 4xx)

Min Tegra Device: Tegra 3

Description

This sample demonstrates how to render skinned meshes using both one or two bones in a vertex shader. Skinning allows organic shapes (such as humans) to deform nicely around joints as they bend. Without skinning, joints have a rigid appearance that is more similar to a mechanical joint like you would see in a robot.

APIs Used

OpenGL ES 2.0

Shared User Interface

The OpenGL samples all share a common app framework and certain user interface elements, centered around the "Tweakbar" panel on the left side of the screen, which lets you interactively control certain variables in each sample.

To show and hide the Tweakbar, simply click or touch the triangular button positioned in the top-left of the view.

Other controls are listed below:

Device	Input	Result
touch	1-Finger Drag	Orbit-rotate the camera
	2-Finger Drag	Move up/down/left/right
	2-Finger Pinch	Scale the view
mouse	Left-Button Drag	Orbit-rotate the camera
	Right-Button Drag	Move up/down/left/right
	Middle-Click Drag	Scale the view (up:out, down:in)
keyboard	Escape	Quit the application
	Tab	Toggle Tweakbar visibility
gamepad	Start	Toggle Tweakbar visibility
	Right Thumbstick	Orbit-rotate the camera
	Left Thumbstick	Move forward/backward. Slide left/right
	Left/Right Triggers	Move up/down

App-Specific Controls

This sample has the following app-specific controls:

Device	Input	Result
keyboard	M	Cycle Rendering Mode
	B	Toggle Single Bone Skinning
	[ and ]	Adjust Animation Speed Slower/Faster
gamepad	Y	Cycle Rendering Mode
	X	Toggle Single Bone Skinning
	Left/Right Shoulder Buttons	Adjust Animation Speed Slower/Faster

Technical Details

Skinning methods

Adjustable Options

Conclusion

Skinning is a good way to improve the quality of animated, organic meshes at a reasonable vertex shader cost.