OpenGL Programming Guide: The Official Guide to Learning OpenGL, Version 4.3, Eighth Edition

Invalidating Framebuffers

Implementations of OpenGL (including OpenGL ES on mobile or embedded devices, most often) may work in limited memory environments. Framebuffers have the potential of taking up considerable memory resources (particularly for multiple, multisampled color attachments and textures). OpenGL provides a mechanism to state that a region or all of a framebuffer is no longer needed and can be released. This operation is done with either glInvalidateSubFramebuffer() or glInvalidateFramebuffer().

void glInvalidateFramebuffer(GLenum target,                         GLsizei numAttachments,                         const GLenum *attachments);void glInvalidateSubFramebuffer(GLenum target,                         GLsizei numAttachmens ...