glMultiDrawArraysIndirect

glMultiDrawArrays is a function in the OpenGL API used for efficiently drawing multiple sets of primitives. Instead of making separate calls to glDrawArrays for each distinct set of vertices, glMultiDrawArrays allows a single call to render all of them. This is particularly useful when dealing with scenes that contain many small, independent geometric objects, such as particles or instances of a repeating model.

The function takes an array of starting indices and an array of counts. Each element in the starting index array specifies the offset into the currently bound vertex data array where a new primitive should begin. The corresponding element in the count array specifies how many vertices should be processed from that starting index to form the primitive. This allows for the rendering of multiple non-contiguous sets of vertices without needing to rebind vertex data or issue multiple draw calls.

By reducing the number of API calls and potential state changes, glMultiDrawArrays can significantly improve rendering performance, especially on systems where the overhead of each individual draw call is noticeable. It offers a more streamlined approach to rendering scenarios that involve drawing many similar or dissimilar geometric elements.