Merge branch 'release/1.0.1'

Author: rm-code

CHANGELOG.md

@@ -1,2 +1,5 @@
+## Version 1.0.1 ( 2016-01-12 )
+- Fix [#1](https://github.com/rm-code/Graphoon/issues/1) - Adjusted force calculation and hopefully made it more stable
+
 ## Version 1.0.0 ( 2016-01-12 )
  - Initial Release

Graphoon/Graph.lua

@@ -36,14 +36,10 @@ function Graph.new()
     ---
     -- Updates the boundaries of the graph.
     -- This represents the rectangular area in which all nodes are contained.
-    -- @param minX - The current minimum x position.
-    -- @param maxX - The current maximum y position.
-    -- @param minY - The current minimum x position.
-    -- @param maxY - The current maximum y position.
     -- @param nx - The new x position to check.
     -- @param ny - The new y position to check.
     --
-    local function updateBoundaries( minX, maxX, minY, maxY, nx, ny )
+    local function updateBoundaries( nx, ny )
         return math.min( minX or nx, nx ), math.max( maxX or nx, nx ), math.min( minY or ny, ny ), math.max( maxY or ny, ny );
     end
 
@@ -158,7 +154,7 @@ function Graph.new()
                 nodeCallback( nodeA );
             end
 
-            minX, maxX, minY, maxY = updateBoundaries( minX, maxX, minY, maxY, nodeA:getPosition() );
+            minX, maxX, minY, maxY = updateBoundaries( nodeA:getPosition() );
         end
     end
 

Graphoon/Node.lua

@@ -2,22 +2,22 @@ local current = (...):gsub('%.[^%.]+$', '');
 
 local Node = {};
 
-local FORCE_SPRING = -0.01;
-local FORCE_CHARGE = 100000;
+local FORCE_SPRING = 0.005;
+local FORCE_CHARGE = 200;
 
 local FORCE_MAX = 4;
-local NODE_SPEED = 8;
+local NODE_SPEED = 128;
 local DAMPING_FACTOR = 0.95;
 
-local DEFAULT_MASS = 0.05;
+local DEFAULT_MASS = 3;
 
 ---
 -- @param id - A unique id which will be used to reference this node.
 -- @param x  - The x coordinate the Node should be spawned at (optional).
 -- @param y  - The y coordinate the Node should be spawned at (optional).
 -- @param anchor - Wether the node should be locked in place or not (optional).
 --
-function Node.new( id, x, y, anchor, ... )
+function Node.new( id, x, y, anchor )
     local self = {};
 
     local px, py = x or 0, y or 0;
@@ -46,17 +46,37 @@ function Node.new( id, x, y, anchor, ... )
         ay = clamp( -FORCE_MAX, ay + fy, FORCE_MAX );
     end
 
+    ---
+    -- Calculates the manhattan distance from the node's coordinates to the
+    -- target coordinates.
+    -- @param tx - The target coordinate in x-direction.
+    -- @param ty - The target coordinate in y-direction.
+    --
+    local function getManhattanDistance( tx, ty )
+        return px - tx, py - ty;
+    end
+
+    ---
+    -- Calculates the actual distance vector between the node's current
+    -- coordinates and the target coordinates based on the manhattan distance.
+    -- @param dx - The horizontal distance.
+    -- @param dy - The vertical distance.
+    --
+    local function getRealDistance( dx, dy )
+        return math.sqrt( dx * dx + dy * dy ) + 0.1;
+    end
+
     ---
     -- Attract this node to another node.
     -- @param node - The node to use for force calculation.
     --
     function self:attractTo( node )
-        local dx, dy = px - node:getX(), py - node:getY();
-        local distance = math.sqrt(dx * dx + dy * dy);
+        local dx, dy = getManhattanDistance( node:getPosition() );
+        local distance = getRealDistance( dx, dy );
         dx = dx / distance;
         dy = dy / distance;
 
-        local strength = FORCE_SPRING * distance;
+        local strength = -1 * FORCE_SPRING * distance * 0.5;
         applyForce( dx * strength, dy * strength );
     end
 
@@ -65,12 +85,12 @@ function Node.new( id, x, y, anchor, ... )
     -- @param node - The node to use for force calculation.
     --
     function self:repelFrom( node )
-        local dx, dy = px - node:getX(), py - node:getY();
-        local distance = math.sqrt(dx * dx + dy * dy);
+        local dx, dy = getManhattanDistance( node:getPosition() );
+        local distance = getRealDistance( dx, dy );
         dx = dx / distance;
         dy = dy / distance;
 
-        local strength = FORCE_CHARGE * ( mass / ( distance * distance ));
+        local strength = FORCE_CHARGE * (( mass * node:getMass() ) / ( distance * distance ));
         applyForce(dx * strength, dy * strength);
     end
 
@@ -119,6 +139,10 @@ function Node.new( id, x, y, anchor, ... )
         mass = nmass;
     end
 
+    function self:getMass()
+        return mass;
+    end
+
     return self;
 end
 

Graphoon/init.lua

@@ -1,5 +1,5 @@
 return {
-    _VERSION     = 'Graphoon v1.0.0',
+    _VERSION     = 'Graphoon v1.0.1',
     _DESCRIPTION = 'A force directed graph algorithm written in Lua.',
     _URL         = 'https://github.com/rm-code/Graphoon',
     _LICENSE     = [[

README.md

@@ -2,6 +2,8 @@
 
 A force directed graph algorithm written in Lua.
 
+![example](https://cloud.githubusercontent.com/assets/11627131/12252902/a5190d90-b8db-11e5-9199-a9fdb61416ac.png)
+
 ## Introduction
 
 _Graphoon_ emerged from the graph calculation code used in both [LoGiVi](https://github.com/rm-code/logivi) and [LoFiVi](https://github.com/rm-code/lofivi).
@@ -60,3 +62,28 @@ Or by using the ```setAnchor``` function:
 -- Invert anchor status
 node:setAnchor( not node:isAnchor(), mouseX, mouseY )
 ```
+
+### Using custom classes for Nodes and Edges
+
+If you prefer to not touch the default classes, you can simply inherit from them and tell Graphoon to use your custom classes instead.
+
+```lua
+local GraphLibraryNode = require('lib.libfdgraph.fd').Node
+
+local CustomNodeClass = {}
+
+-- You can pass additional arguments to your custom class. Just make sure the
+-- default parameters ar in the right order.
+function CustomNodeClass.new( id, x, y, anchor, ... )
+    local self = GraphLibraryNode.new( id, x, y, anchor )
+
+	-- ... Custom code
+end
+
+return CustomNodeClass
+```
+
+```lua
+local GraphLibrary = require('Graphoon').Graph
+GraphLibrary.setNodeClass( require('CustomNodeClass') )
+```