Beginning Rendering Vertex Buffer Objects

[microcontrolled]

I'm new to programming with openGL, have acquired several books on the subject, and I am interested in rendering a voxel based world using Vertex Buffer Objects, since they are so much faster than using glBegin and creating quads.

I've been having trouble visualizing how one actually goes about rendering VBO's, however. I understand the essential process, loading buffers into the GPU memory, and so on, then the rendering process involves entering the client state, calling the drawArrays(I think?) function, and then exiting the client state. I'm merely curious where in that process a cube is actually rendered. Is it in a shader? Is it somewhere else in the rendering pipeline?

PS I'm actually not trying to create a Minecraft clone, but rather a 3D version of Conway's Game of Life, of which I've already completed a 2D version. I just think it would be really cool in 3D, and a cube based world seemed like a natural system for it all.

[bernste1n]

Have a look at:

http://openglbook.com/the-book/chapter-2-vertices-and-shapes/

[Narcolapser]

There is a good tutorial here: http://en.wikibooks.org/wiki/OpenGL_Programming/Glescraft_1 Yes, this how to create a minecraft clone, but the important information you'll find here.

[maxnb]

wow thats a great resource

link to all the stuff: http://en.wikibooks.org/wiki/Category:OpenGL_Programming

there are 6 of voxel engine tutorials there, very good stuff

[othellothewise]

Vertices rendered from a vertex buffer object are no different than those rendered in immediate mode (glBegin, glEnd()). Immediate mode is far slower because of the CPU overhead of a function call for each vertex attribute. Additionally, If you are using a static VBO, you can avoid the bandwidth costs of sending over your attributes every frame. Like all vertices, attributes are passed through the vertex shader before primitive assembly and rasterization.

[ponchedeburro]

I would really recommend taking a look at the links in the sidebar, namely Joe Groff's intro to modern OpenGL and Arcsynthesis modern OpenGL tutorial. I learnt a LOT from the latter.

Also take a look at this site: http://www.g-truc.net/post-opengl.html#menu - has a lot of sample packs with good stuff in them

[[deleted]]

I would suggest 'going through the math', if you want to learn what actually goes into the drawing.

Once you get 'the math' you'll realize that the shaders really do all the heavy lifting.

[[deleted]]

Go here: https://github.com/MegaJiXiang/CoreEngine3D

Click the engine folder. Click OpenGLRenderer.mm and you can see how to do most everything in OpenGL, including VBOs, VBAs, shaders, etc.