Weighted Blended OIT Sample

Category:  Performance Visuals
Min PC GPU: Fermi-based (GTX 4xx)
Min Tegra Device: Tegra K1


Weighted Blended OIT Sample demonstrates how plausible OIT (Order Independent Transparency) can be rendered in a single geometry pass without any depth sorting, as described in McGuire and Bavoil 2013. The idea is to use additive blending to compute a weighted average of the translucent colors with a weighting function that falls off as the linear depth increases. This sample compares the quality and performance of Weighted Blended OIT with Depth Peeling.

APIs Used

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

Technical Details

This sample is an implementation of the Weighted Blended OIT (Order Independent Transparency) algorithm from this research paper:
McGuire and Bavoil, Weighted Blended Order-Independent Transparency, Journal of Computer Graphics Techniques (JCGT), vol. 2, no. 2, 122--141, 2013.


This SDK sample has two rendering methods for order-independent transparency:

See Also



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