Utils to control the layout of docks

By default the windows are added with an average layout. This can be
changed to specified proportions provided you have insight on how the
layout tree is structured.

Assets/UIDock/Root.cs

@@ -1118,8 +1118,11 @@ private void UpdateWindowsManagement(bool moveSashes, bool regenSashes)
 
                 this.dirtySashPosition = false;
             }
+        }
 
-
+        public void ForceLayout()
+        {
+            this.UpdateWindowsManagement(true, true);
         }
 
         /// <summary>
@@ -1888,5 +1891,103 @@ protected override void OnRectTransformDimensionsChange()
             this.SetDirtySashPos();
         }
 
+        protected Dock GetDockAtAddress(bool lenient, params int [] ri)
+        { 
+            if(ri == null || ri.Length == 0)
+                return this.root;
+
+            Dock dit = this.root;
+            for(int i = 0; i < ri.Length; ++i)
+            { 
+                int idx = ri[i];
+
+                if(
+                    dit.IsContainerType() == false || 
+                    dit.children == null || 
+                    idx < 0 || 
+                    idx >= dit.children.Count)
+                {
+                    return lenient ? dit : null;
+                }
+
+                dit = dit.children[idx];
+            }
+            return dit;
+        }
+
+        protected bool ResizeDock(Dock d, params float [] rf)
+        { 
+            if( d == null || 
+                (d.dockType != Dock.Type.Horizontal && d.dockType != Dock.Type.Vertical))
+            { 
+                return false;
+            }
+
+            float avg = 0.0f;
+            foreach(float f in rf)
+                avg += f;
+
+            if(rf.Length > 0)
+                avg /= rf.Length;
+
+            if(avg == 0.0f)
+                avg = 1.0f;
+
+            // These values are treated as proportions, they'll be converted to actual pixel sizes on the layout.
+            float totalProp = d.children.Count * avg;
+
+            if (d.dockType == Dock.Type.Horizontal)
+            {
+                float totalW = 0.0f;
+                for (int i = 0; i < d.children.Count; ++i)
+                    totalW += d.children[i].cachedPlace.width;
+
+                float fx = d.cachedPlace.x;
+                for (int i = 0; i < d.children.Count; ++i)
+                { 
+                    float nw = (i < rf.Length) ? rf[i] : avg;
+                    float prop = nw / totalProp * totalW;
+                    d.children[i].cachedPlace.x = fx;
+                    d.children[i].cachedPlace.width = nw;
+
+                    fx += nw;
+                    fx += this.props.sashWidth;
+                    UpdateDockedLayoutHeirarchy(new LayoutEntry(d.children[i], d.children[i].cachedPlace));
+                }
+            }
+            else
+            {
+                float totalH = 0.0f;
+                for (int i = 0; i < d.children.Count; ++i)
+                    totalH += d.children[i].cachedPlace.height;
+
+                float fy = d.cachedPlace.y;
+                for (int i = 0; i < d.children.Count; ++i)
+                { 
+                    float nh = (i < rf.Length) ? rf[i] : avg;
+                    float prop = nh / totalProp * totalH;
+                    d.children[i].cachedPlace.y = fy;
+                    d.children[i].cachedPlace.height = nh;
+
+                    fy += nh;
+                    fy += this.props.sashWidth;
+                    UpdateDockedLayoutHeirarchy(new LayoutEntry(d.children[i], d.children[i].cachedPlace));
+                }
+            }
+
+            this.dirtySashPosition = true;
+            this.SetDirty();
+            return true;
+        }
+
+        public bool ResizeAddressWithProportions(int [] addr, float [] proportions)
+        { 
+            Dock d = GetDockAtAddress(false, addr);
+            if(d == null)
+                return false;
+
+            return ResizeDock(d, proportions);
+        }
+
     }
 }