protected String textureFragmentShader() {
    StringBuilder str = new StringBuilder(FRAGMENT_PREAMBLE);

    str.append(textureUniforms());
    str.append(textureVaryings());

    str.append("void main(void) {\n");

    str.append(textureColor());
    str.append(textureTint());
    str.append(textureAlpha());

    str.append(
      "  gl_FragColor = textureColor;\n" +
      "}");

    return str.toString();
  }
protected String textureFragmentShader ( ) { StringBuilder str = new StringBuilder ( FRAGMENT_PREAMBLE ) ; str . append ( textureUniforms ( ) ) ; str . append ( textureVaryings ( ) ) ; str . append ( "void main(void) {\n" ) ; str . append ( textureColor ( ) ) ; str . append ( textureTint ( ) ) ; str . append ( textureAlpha ( ) ) ; str . append ( "  gl_FragColor = textureColor;\n" + "}" ) ; return str . toString ( ) ; }
Returns the texture fragment shader program. Note that this program <em>must</em> preserve the
use of the existing varying attributes. You can add new varying attributes, but you cannot
remove or change the defaults.