code: public void setTexCoords(float [] texCoords, int index)
      {
          String key = (index > 0) ? (KEY_TEXCOORD + index) : KEY_TEXCOORD;
          mVertices.setFloatArray(key, texCoords);
      }
docs: Populates a set of texture coordinates for the mesh.
  <p>
  A mesh may have multiple sets of texture coordinates
  Each texture coordinate is represented as a packed {@code float} pair:
  <p>
  <code>{ u0, v0, u1, v1, u2, v2, ...}</code>
  This function updates the <i>a_texcoordN</i> vertex attribute where N is
  the value of the <i>index</i> argument.
  @param texCoords
  Array containing the packed texture coordinate data.
  @param index
  0-based index indicating which set of texture coordinates to update.
  @see #getTexCoords()
  @see GVRVertexBuffer#setFloatArray(String, float[])