This is 10th post on OpenGL and Vulkan interoperability with EXT_external_objects and EXT_external_objects_fd. We’ll see the last use case I’ve written for Piglit to test the extensions implementation on various mesa drivers as part of my work for Igalia. In this test a stencil buffer is allocated and filled with a pattern by Vulkan and then it is used in OpenGL to render something else. We validate that the pattern has been imported correctly and we repeat the process for other depth-stencil formats.