Combine some duplicate code in AA using template
BUG=skia:
Change-Id: Id048425e8199167feba0268f89f526bbf5b7242b
Reviewed-on: https://skia-review.googlesource.com/9832
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Yuqian Li <liyuqian@google.com>
diff --git a/src/core/SkScanPriv.h b/src/core/SkScanPriv.h
index 606929d..eca3c9c 100644
--- a/src/core/SkScanPriv.h
+++ b/src/core/SkScanPriv.h
@@ -38,4 +38,43 @@
void sk_blit_above(SkBlitter*, const SkIRect& avoid, const SkRegion& clip);
void sk_blit_below(SkBlitter*, const SkIRect& avoid, const SkRegion& clip);
+template<class EdgeType>
+static inline void remove_edge(EdgeType* edge) {
+ edge->fPrev->fNext = edge->fNext;
+ edge->fNext->fPrev = edge->fPrev;
+}
+
+template<class EdgeType>
+static inline void insert_edge_after(EdgeType* edge, EdgeType* afterMe) {
+ edge->fPrev = afterMe;
+ edge->fNext = afterMe->fNext;
+ afterMe->fNext->fPrev = edge;
+ afterMe->fNext = edge;
+}
+
+template<class EdgeType>
+static void backward_insert_edge_based_on_x(EdgeType* edge) {
+ SkFixed x = edge->fX;
+ EdgeType* prev = edge->fPrev;
+ while (prev->fPrev && prev->fX > x) {
+ prev = prev->fPrev;
+ }
+ if (prev->fNext != edge) {
+ remove_edge(edge);
+ insert_edge_after(edge, prev);
+ }
+}
+
+// Start from the right side, searching backwards for the point to begin the new edge list
+// insertion, marching forwards from here. The implementation could have started from the left
+// of the prior insertion, and search to the right, or with some additional caching, binary
+// search the starting point. More work could be done to determine optimal new edge insertion.
+template<class EdgeType>
+static EdgeType* backward_insert_start(EdgeType* prev, SkFixed x) {
+ while (prev->fPrev && prev->fX > x) {
+ prev = prev->fPrev;
+ }
+ return prev;
+}
+
#endif