+ /* 4. Final reordering:
+ *
+ * After the localized forms and basic shaping forms GSUB features have been
+ * applied (see below), the shaping engine performs some final glyph
+ * reordering before applying all the remaining font features to the entire
+ * cluster.
+ *
+ * o Reorder matras:
+ *
+ * If a pre-base matra character had been reordered before applying basic
+ * features, the glyph can be moved closer to the main consonant based on
+ * whether half-forms had been formed. Actual position for the matra is
+ * defined as “after last standalone halant glyph, after initial matra
+ * position and before the main consonant”. If ZWJ or ZWNJ follow this
+ * halant, position is moved after it.
+ *
+ * o Reorder reph:
+ *
+ * Reph’s original position is always at the beginning of the syllable,
+ * (i.e. it is not reordered at the character reordering stage). However,
+ * it will be reordered according to the basic-forms shaping results.
+ * Possible positions for reph, depending on the script, are; after main,
+ * before post-base consonant forms, and after post-base consonant forms.
+ *
+ * 1. If reph should be positioned after post-base consonant forms,
+ * proceed to step 5.
+ *
+ * 2. If the reph repositioning class is not after post-base: target
+ * position is after the first explicit halant glyph between the
+ * first post-reph consonant and last main consonant. If ZWJ or ZWNJ
+ * are following this halant, position is moved after it. If such
+ * position is found, this is the target position. Otherwise,
+ * proceed to the next step.
+ *
+ * Note: in old-implementation fonts, where classifications were
+ * fixed in shaping engine, there was no case where reph position
+ * will be found on this step.
+ *
+ * 3. If reph should be repositioned after the main consonant: from the
+ * first consonant not ligated with main, or find the first
+ * consonant that is not a potential pre-base reordering Ra.
+ *
+ *
+ * 4. If reph should be positioned before post-base consonant, find
+ * first post-base classified consonant not ligated with main. If no
+ * consonant is found, the target position should be before the
+ * first matra, syllable modifier sign or vedic sign.
+ *
+ * 5. If no consonant is found in steps 3 or 4, move reph to a position
+ * immediately before the first post-base matra, syllable modifier
+ * sign or vedic sign that has a reordering class after the intended
+ * reph position. For example, if the reordering position for reph
+ * is post-main, it will skip above-base matras that also have a
+ * post-main position.
+ *
+ * 6. Otherwise, reorder reph to the end of the syllable.
+ *
+ * o Reorder pre-base reordering consonants:
+ *
+ * If a pre-base reordering consonant is found, reorder it according to
+ * the following rules:
+ *
+ * 1. Only reorder a glyph produced by substitution during application
+ * of the feature. (Note that a font may shape a Ra consonant with
+ * the feature generally but block it in certain contexts.)
+ *
+ * 2. Try to find a target position the same way as for pre-base matra.
+ * If it is found, reorder pre-base consonant glyph.
+ *
+ * 3. If position is not found, reorder immediately before main
+ * consonant.
+ */
+
+ /* TODO */
+
+
+