VBO

A Vertex Buffer Object (VBO) is an OpenGL object used to store vertex data in GPU memory to speed up rendering. VBOs were introduced with the OpenGL 1.5 core specification, following the ARB_vertex_buffer_object extension. By keeping vertex data on the GPU, VBOs reduce CPU‑to‑GPU data transfers and enable efficient reuse of data across many frames.

VBOs are created with glGenBuffers, bound with glBindBuffer, and filled with glBufferData or glBufferSubData. The GL_ARRAY_BUFFER target stores vertex attributes, while GL_ELEMENT_ARRAY_BUFFER stores index data for glDrawElements. Data may be stored as interleaved attributes in a single buffer or as separate buffers per attribute. VBOs are commonly used with Vertex Array Objects (VAOs) to retain their binding state and attribute configuration; vertex attributes are specified with glVertexAttribPointer and enabled with glEnableVertexAttribArray.

Data usage hints specify how the buffer will be updated: GL_STATIC_DRAW for rarely changed data, GL_DYNAMIC_DRAW for data updated frequently, and GL_STREAM_DRAW for data streamed per frame. For dynamic data, updates can be done with glBufferSubData or by mapping the buffer with glMapBufferRange; orphaning by replacing the buffer with a new allocation can avoid stalls.

Performance considerations include lower CPU–GPU bandwidth, improved memory locality, and better parallelism. The layout choice, interleaved versus separate attribute arrays, affects access patterns. Efficient VBO use also depends on shader attribute locations and proper VAO state management.

See also OpenGL Vertex Array Objects and the broader OpenGL rendering pipeline. VBOs are a central component of modern graphics APIs for efficient, reusable vertex data storage in GPU memory.