[font] Do user-space conversion when chaining up to parent font
diff --git a/src/hb-font-private.hh b/src/hb-font-private.hh
index 203cd23..f60ce97 100644
--- a/src/hb-font-private.hh
+++ b/src/hb-font-private.hh
@@ -118,6 +118,34 @@
inline hb_position_t em_scale_x (int16_t v) { return em_scale (v, this->x_scale); }
inline hb_position_t em_scale_y (int16_t v) { return em_scale (v, this->y_scale); }
+ /* Convert from parent-font user-space to our user-space */
+ inline hb_position_t parent_scale_x_distance (hb_position_t v) {
+ if (unlikely (parent && parent->x_scale != x_scale))
+ return v * (int64_t) this->x_scale / this->parent->x_scale;
+ return v;
+ }
+ inline hb_position_t parent_scale_y_distance (hb_position_t v) {
+ if (unlikely (parent && parent->y_scale != y_scale))
+ return v * (int64_t) this->y_scale / this->parent->y_scale;
+ return v;
+ }
+ inline hb_position_t parent_scale_x_position (hb_position_t v) {
+ return parent_scale_x_distance (v); /* We don't have translation right now */
+ }
+ inline hb_position_t parent_scale_y_position (hb_position_t v) {
+ return parent_scale_y_distance (v); /* We don't have translation right now */
+ }
+
+ inline void parent_scale_distance (hb_position_t *x, hb_position_t *y) {
+ *x = parent_scale_x_distance (*x);
+ *y = parent_scale_y_distance (*y);
+ }
+ inline void parent_scale_position (hb_position_t *x, hb_position_t *y) {
+ *x = parent_scale_x_position (*x);
+ *y = parent_scale_y_position (*y);
+ }
+
+
private:
inline hb_position_t em_scale (int16_t v, int scale) { return v * (int64_t) scale / this->face->upem; }
};
