Will an Octree improve performance if my scene contains less than 200K vertices?

Question

I am finally making the move to OpenGL ES 2.0 and am taking advantage of a VBO to load all of the scene data onto the graphics cards memory. However my scene is only around the 200,000 vertices in size ( and I know it depends on hardware somewhat ) but does anyone think an octree would make any sense in this instance ? ( incidentally because of the view point at least 60% of the scene is visible most of the time ) Clearly I am trying to avoid having to implementing an Octree at such an early stage of my GLSL coding life !

Answer 1

There is no need to be worried about optimization and performance if the App you are coding is for learning purpose only. But given your question, apparently you intend to make a commercial App.

Only using VBO will not solve problems on performance for you App, specially as you mentioned that you meant it to run on mobile devices. OpenGL ES has an optimized option for drawing called GL_TRIANGLE_STRIP, which is worth particularly for complex geometry.

Also interesting to add up in improving performance is to apply Bump Masking, for the case you have textures in your model. With these two approaches you App will be remarkably improved.

As you mention that your entire scenery is visible all the time, you should also use level of detail (LOD). To implement geometry LOD, you need a different mesh for each LOD that you wish to use, and each level has fewer polygons than the closest one. You can make yourself the geometry for each LOD, or you can also apply some 3D software to make it automatically.

Some tools are free and you can access and use it to automatically perform generic optimization directly on your GLSL ES code, and it is really worth checking.