Single-Pass Stereo Rendering

What is Single-Pass Stereo Rendering?

Single-Pass Stereo Rendering is a performance optimization technique that renders both eye views simultaneously into a packed texture, significantly reducing CPU workload by sharing culling and shadow data between views for more efficient VR experiences.

This rendering approach dramatically improves performance compared to traditional multi-pass methods by processing scene geometry only once while generating separate viewpoints for each eye.

How does Single-Pass Stereo Rendering work?

Single-Pass Stereo Rendering works by expanding vertex shaders to automatically generate appropriate positions for both eyes, then rendering both views simultaneously into a single wider texture that contains both left and right eye images side by side.

This shared rendering process eliminates redundant operations including scene traversal, visibility determination, shadow calculations, and geometry processing that would otherwise be performed twice. The efficiency gains primarily benefit CPU performance by reducing draw calls and state changes, while still requiring appropriate GPU resources to process the expanded rendering target.

How is Single-Pass Stereo Rendering used?

Modern implementations often incorporate additional optimizations like stereo instancing (a hardware-accelerated variation that achieves similar benefits with even greater efficiency) when supported by the target platform.

For VR developers, single-pass stereo rendering represents a critical tool for achieving consistent frame rates and comfortable experiences while maximizing available resources for higher visual fidelity, more complex physics, or richer gameplay systems within strict performance constraints.