The CL_GL extension

This extension can be used by referencing the the project file opencl-cl_gl.gpr. It enables you to share texture and renderbuffer objects from OpenGL with OpenCL. It depends on OpenGLAda. This extension provides child classes to some of the OpenCL class types to enable the memory object sharing capabilities.

To create an OpenCL context that allows this, you have to have an active OpenGL context (in an active window or fullscreen). Then, you can create your context with

CL.Contexts.CL_GL.Constructors.Create

This context class does not look so different from the usual context class on its own; but it is actually quite different on the inside, because it is linked to the OpenGL context that was active when you created it. You can now create a specialized command queue with it by means of

CL.Command_Queues.CL_GL.Constructors.Create

Again, this queue does not look very different from a normal queue. But now, you can use the image creation functions in

CL.Memory.Images.CL_GL

These require an OpenGL enabled command queue, which you have just created. You can now create OpenCL image objects from OpenGL texture and renderbuffer objects. To manipulate these objects, you have to acquire them from OpenGL and afterwards release them with

CL.Queueing.CL_GL.Acquire_GL_Objects
CL.Queueing.CL_GL.Release_GL_Objects