MTLRenderPassDescriptor

mtlrenderpassdescriptor.png

MTLRenderPassDescriptorはobject contains a collection of attachments that are the rendering destination for pixels generated by a rendering pass.
The MTLRenderPassDescriptor class also is used as the destination for visibility information generated by a rendering pass.

colorattatchment

色データを貯めてるアタッチメント
型を調べてみると

Swift.ImplicitlyUnwrappedOptional<MTLRenderPassColorAttachmentDescriptor>

こいつの親クラスが
MTLRenderPassAttachmentDescriptor

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