Recall from lesson one that OpenGL ES is a native system library, whereas Java on Android runs in a virtual machine. Whether we are using vertex buffer objects or not, we need to first store our data in a client-side direct buffer.

Vertex buffer object, separate buffers.

This lesson has been setup to use four different modes: The main difference is that there is an additional step to upload the data into graphics memory, and an additional call to bind to this buffer when rendering. Once you understand how to render using client-side memory, it’s actually not too hard to switch to using VBOs. Understanding client-side buffers in more detail This understanding of how OpenGL ES works with the vertex arrays will be crucial to understanding this lesson.

Please read Android Lesson One: Getting Started for an intro on how to upload the vertices from client-side memory. Instead of transferring vertex information from client memory every frame, the information will be transferred once and rendering will then be done from this graphics memory cache. What can we do about this? We can use vertex buffer objects. This is fine when there is not a lot of data to transfer, but as our scenes get more complex with more objects and triangles, this can impose an extra cost on the CPU and memory usage. Up until now, all of our lessons have been storing our object data in client-side memory, only transferring it into the GPU at render time. What are vertex buffer objects, and why use them? Problems and pitfalls, and what to do about them.

The difference between using a single buffer with all the data packed in, or multiple buffers.How to define and render from vertex buffer objects.In this lesson, we’ll introduce vertex buffer objects (VBOs), how to define them, and how to use them. Here is what we are going to cover:

Opengl es 2.0 vertex array object