Add and use TileIndex positionRelativeParent

modules/globebrowsing/tile/tileindex.cpp

@@ -79,6 +79,12 @@ namespace globebrowsing {
         return *this;
     }
 
+
+    glm::vec2 TileIndex::positionRelativeParent() const{
+        // In OpenGL, positive y direction is up
+        return glm::vec2(isEastChild() ? 0.5 : 0, isNorthChild() ? 0.5 : 0);
+    }
+
     /**
     Gets the tile at a specified offset from this tile.
     Accepts delta indices ranging from [-2^level, Infinity[

modules/globebrowsing/tile/tileindex.h

@@ -72,24 +72,26 @@ struct TileIndex {
 
     TileIndex& operator-=(unsigned int levels);
 
-    bool isWestChild() const {
+    inline bool isWestChild() const {
         return x % 2 == 0;
     }
 
-    bool isEastChild() const {
+    inline bool isEastChild() const {
         return x % 2 == 1;
     }
 
-    bool isNorthChild() const {
+    inline bool isNorthChild() const {
         return y % 2 == 0;
     }
 
-    bool isSouthChild() const {
+    inline bool isSouthChild() const {
         return y % 2 == 1;
     }
 
     TileIndex child(Quad q) const;
 
+    glm::vec2 positionRelativeParent() const;
+
 
     std::string toString() const;
 

modules/globebrowsing/tile/tileselector.cpp

@@ -80,14 +80,7 @@ namespace globebrowsing {
         uv.uvOffset *= 0.5;
         uv.uvScale *= 0.5;
 
-        if (tileIndex.isEastChild()) {
-            uv.uvOffset.x += 0.5;
-        }
-
-        // In OpenGL, positive y direction is up
-        if (tileIndex.isNorthChild()) {
-            uv.uvOffset.y += 0.5;
-        }
+        uv.uvOffset += tileIndex.positionRelativeParent();
 
         --tileIndex;
     }