| renderPass | The RenderPass object this subpass is part of. |
| colors | Array of attachments to be used as the color render targets in this subpass. All attachments in this array must also be declared in the RenderPass constructor. |
| inputs | Array of attachments to be used as input attachments in this subpass. All attachments in this array must also be declared in the RenderPass constructor. |
| readOnlyDepth | If true, the depth attachment is read-only in this subpass. Some renderers require this in order to be able to use the depth attachment as input. |
Create a subpass and start it.