var currentTextureUnit = null ; 
var SetActiveTexture = function (state, textureUnit){ 
var gl = state.gl; 
if (textureUnit === undefined) { 
textureUnit = gl.TEXTURE0 + state.maxTextures - 1; 
} 
if (currentTextureUnit !== textureUnit) { 
gl.activeTexture(textureUnit); 
currentTextureUnit = textureUnit; 
} 
return currentTextureUnit; 
} 
; 
module.exports = SetActiveTexture;