If Z buffer can't be accessed as a texture, then depth is rendered in additional rendering pass, using shader replacement.
如果Z缓冲不能被以纹理的方式访问，那么深度将在额外的渲染处理中被使用着色器替代技术渲染。
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Where the severity of deterioration requires replacement of a distinctive feature, the new feature will match the old in design, color, texture, and, where possible, materials.
Camera actually builds the depth texture using Shader Replacement feature, so it's entirely possible to do that yourself, in case you need a different G-buffer setup.