code: public void addQuad (int tint, AffineTransform xf,
                         float left, float top, float right, float bottom,
                         float sl, float st, float sr, float sb) {
      addQuad(tint, xf.m00, xf.m01, xf.m10, xf.m11, xf.tx, xf.ty,
              left, top, right, bottom, sl, st, sr, sb);
    }
docs: Adds a transformed axis-aligned quad to this batch.
  {@code left, top, right, bottom} define the bounds of the quad.
  {@code sl, st, sr, sb} define the texture coordinates.