Framebuffer pass attachment description. This class contains the list of attachment descriptions for a framebuffer pass. Each points with an index to a previously supplied list of texture attachments. Multipass framebuffers can optimize some configurations in mobile, on desktop they provide little to no advantage. Color attachments in order starting from 0. If this attachment is not used by the shader, pass ATTACHMENT_UNUSED to skip. Depth attachment. ATTACHMENT_UNUSED should be used if no depth buffer is required for this pass. Used for multipass framebuffers (more than one render pass). Converts an attachment to an input. Make sure to also supply it properly in the [RDUniform] for the uniform set. Attachments to preserve in this pass (otherwise they are erased). If the color attachments are multisampled, non-multisampled resolve attachments can be provided.