如何将多个纹理发送到WebGL中的片段着色器？

So in the javascript portion of my code, here is the snippet that actually sends an array of pixels to the vertex and fragment shaders- but I am only working with 1 texture when I get to those shaders- is there anyway that I can send two textures at a time? if so, how would I 'catch' both of them on the GLSL side of the codee?So in the javascript portion of my code, here i