code: public int bindShader(GVRContext context, GVRShaderData material, String vertexDesc)
      {
          String signature = getClass().getSimpleName();
          GVRShaderManager shaderManager = context.getShaderManager();
  
          synchronized (shaderManager)
          {
              int nativeShader = shaderManager.getShader(signature);
              if (nativeShader == 0)
              {
                  nativeShader = addShader(shaderManager, signature, material);
              }
              return nativeShader;
          }
      }
docs: Select the specific vertex and fragment shader to use with this material.
  
  The shader template is used to generate the sources for the vertex and
  fragment shader based on the material properties only.
  It will ignore the mesh attributes and all lights.
  
  @param context
  GVRContext
  @param material
  material to use with the shader
  @return ID of vertex/fragment shader set