UV: internal changes to picking

Nothing user visible, only things needed for multi-object support,
making picking functions more flexible too.

- Support passing in an initialized hit-struct,
  so it's possible to do multiple nearest calls on the same hit data.
- Replace manhattan distance w/ squared distance
  so they can be compared.
- Return success to detect changes to a hit-data
  which might already be initialized (also more readable).

1 files changed, 20 insertions, 7 deletions

diff --git a/source/blender/editors/uvedit/uvedit_intern.h b/source/blender/editors/uvedit/uvedit_intern.h
index e028c08091c..b5ff46e9219 100644
--- a/source/blender/editors/uvedit/uvedit_intern.h
+++ b/source/blender/editors/uvedit/uvedit_intern.h
@@ -51,18 +51,31 @@ void  uv_poly_center(struct BMFace *f, float r_cent[2], const int cd_loop_uv_off
 
 /* find nearest */
 
-typedef struct NearestHit {
+typedef struct UvNearestHit {
+	/** Always set if we have a hit. */
 	struct BMFace *efa;
 	struct MTexPoly *tf;
 	struct BMLoop *l;
 	struct MLoopUV *luv, *luv_next;
-	int lindex;  /* index of loop within face */
-} NearestHit;
+	/** Index of loop within face. */
+	int lindex;
+	/** Needs to be set before calling nearest functions. */
+	float dist_sq;
+} UvNearestHit;
 
-void uv_find_nearest_vert(struct Scene *scene, struct Image *ima, struct BMEditMesh *em,
-                          const float co[2], const float penalty[2], struct NearestHit *hit);
-void uv_find_nearest_edge(struct Scene *scene, struct Image *ima, struct BMEditMesh *em,
-                          const float co[2], struct NearestHit *hit);
+#define UV_NEAREST_HIT_INIT { .dist_sq = FLT_MAX, }
+
+bool uv_find_nearest_vert(
+        struct Scene *scene, struct Image *ima, struct BMEditMesh *em,
+        const float co[2], const float penalty_dist, struct UvNearestHit *hit_final);
+
+bool uv_find_nearest_edge(
+        struct Scene *scene, struct Image *ima, struct BMEditMesh *em,
+        const float co[2], struct UvNearestHit *hit_final);
+
+bool uv_find_nearest_face(
+        struct Scene *scene, struct Image *ima, struct BMEditMesh *em,
+        const float co[2], struct UvNearestHit *hit_final);
 
 /* utility tool functions */