WebGL - Is the gl.useProgram() an expensive call to make?

Question

I'm wondering if this API method used to load a shader program is expensive or not to call? Im considering making this call per object in my 3D scene.

gl.useProgram(shaderProgram);

thanks

Answer 1

• this says it's better to use glUseProgram than is to glAttachShader+glLinkProgram
• this says that changing shaders is always heavy, but glUseProgram is least heavy
• this says it's generally efficient
• this says that moderate and careful use won't become a bottleneck
• this talks a bit about shader-switching performance optimization

So, conslusion: use it moderately. If you don't have much objects - great, if you do - try optimizing shader switching, or reusing shaders multiple times, or use same shader that utilizes branching somehow.

useProgram has got medium performance hit. It's not super-light, neither it's super-heavy like linkProgram and compileShader.

Hope this helps.