Virtual reality (VR) renderers driving CAVEs and similar immersive environments use the off-axis stereo camera model so that a tracked user can move freely in front of the projection plane. Geometrically, off-axis projection results in asymmetric viewing frusta and generalizes the ubiquitous perspective camera model to support positioning off the center of the projection plane. VR renderers often integrate with larger visualization systems that rely on libraries for position tracking and pose estimates, for ray tracing-based rendering, and for user interaction. We demonstrate different strategies to implement off-axis stereo projection within the constraints of given VR applications and ray tracing libraries. We aim for minimal to no adjustments required to the internal camera representation of such libraries. We include host and shader code with the article that can be directly integrated in custom applications.

翻译：驱动CAVE系统及类似沉浸式环境的虚拟现实渲染器采用离轴立体相机模型，使受追踪用户可在投影平面前方自由移动。从几何角度而言，离轴投影会产生非对称视锥体，将通用的透视相机模型扩展为支持偏离投影平面中心的位置定位。虚拟现实渲染器常与依赖位置追踪、姿态估计光线追踪渲染及用户交互库的大型可视化系统协同工作。本文展示了在既定虚拟现实应用与光线追踪库约束下实现离轴立体投影的多种策略，力求对该类库内部相机表征的调整幅度降至最低乃至为零。随文附带的宿主程序与着色器代码可直接集成至定制化应用中。