title: In metal how to clear the depth buffer or the stencil buffer?
body: <p>In metal, when I already have a RenderCommandEncoder and when I already did some job with it, how can I clear the <strong>depth buffer</strong> or the <strong>stencil buffer</strong> (but not both I need to keep one)? For example, in OpenGl we have <code>glClearDepthf</code> / <code>GL_DEPTH_BUFFER_BIT</code> and <code>glClearStencil</code> / <code>GL_STENCIL_BUFFER_BIT</code> but I didn't find any equivalent in metal.</p>