currentRenderPassDescriptor

This convenience property provides a render pass descriptor to render into the current drawable’s texture. MTKView doesn’t use this descriptor, and there’s no requirement for your application to use it.

This property is nil if the view’s device property isn’t set or if currentDrawable is nil. Your app should check that currentRenderPassDescriptor isn’t nil before attempting to use it.

The view configures the render pass as follows:

• If multisampling isn’t enabled—The color attachment at index 0 of the render pass descriptor points to the texture assigned to the current drawable, with a load action of MTLLoadAction.clear and a store action of MTLStoreAction.store.

• If you’ve enabled multisampling—The color attachment at index 0 of the render pass descriptor points to the multisample texture, the resolve texture points to the texture assigned to the current drawable, and the attachment has a load action of MTLLoadAction.clear and a store action of MTLStoreAction.multisampleResolve.

• If you’ve specified a depth or stencil target—The render pass configures the appropriate targets, with a load action of MTLLoadAction.clear and a store action of MTLStoreAction.dontCare.