OpenGL Insights

40. SceneJS: A WebGL-Based Scene Graph Engine 581

Fr ameworks using this technique typically reduce the viewport to a 1 × 1region

at the pick coordinates for efficiency while rendering the pickbuffer. SceneJS uses the

entire original viewport so that it can retain the pick buffer to support fast repicking

at different coordinates for the case when nothing has changed in the image since the

last pick. This supports fast mouseover effects such as tool-tips.

40.5 Conclusion

When aiming for high-performance 3D graphics in the browser , the greatest per-

formance bottleneck is JavaScript overhead. To overcome this bottleneck, WebGL

applications can greatl ...