Graphoon/fd/Graph.lua
2016-01-12 02:30:41 +01:00

258 lines
7.7 KiB
Lua

local current = (...):gsub('%.[^%.]+$', '');
local Node = require(current .. '.Node');
local Edge = require(current .. '.Edge');
local Graph = {};
function Graph.new()
local self = {};
local nodes = {};
local edges = {};
local edgeIDs = 0;
local minX, maxX, minY, maxY;
-- ------------------------------------------------
-- Local Functions
-- ------------------------------------------------
---
-- Sets the graph's boundaries to nil.
--
local function resetBoundaries()
minX, maxX, minY, maxY = nil, nil, nil, nil;
end
---
-- @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 )
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
---
-- Adds a new edge between two nodes.
-- @param origin - The node from which the edge originates.
-- @param target - The node to which the edge is pointing to.
--
local function addEdge( origin, target )
for _, edge in pairs( edges ) do
if edge.origin == origin and edge.target == target then
error "Trying to connect nodes which are already connected.";
end
end
assert( origin ~= target, "Tried to connect a node with itself." );
edges[edgeIDs] = Edge.new( edgeIDs, origin, target );
edgeIDs = edgeIDs + 1;
end
-- ------------------------------------------------
-- Public Functions
-- ------------------------------------------------
---
-- Add a node to the graph.
-- @param id - The ID will be used to reference the Node inside of the graph.
-- @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 self:addNode( id, x, y, anchor, ... )
assert( not nodes[id], "Node IDs must be unique." );
nodes[id] = Node.new( id, x, y, anchor, ... );
return nodes[id];
end
---
-- Remove a node from the graph.
-- This will also remove all edges pointing to or originating from this node.
-- @param node - The node to remove from the graph.
--
function self:removeNode( node )
nodes[node:getID()] = nil;
self:removeEdges( node );
end
---
-- Adds a new edge between two nodes.
-- @param origin - The node from which the edge originates.
-- @param target - The node to which the edge is pointing to.
--
function self:connectNodes( origin, target )
addEdge( origin, target );
end
---
-- Adds a new edge between two nodes referenced by their IDs.
-- @param origin - The node id from which the edge originates.
-- @param target - The node id to which the edge is pointing to.
--
function self:connectIDs( originID, targetID )
assert( nodes[originID], string.format( "Tried to add an Edge to the nonexistent Node \"%s\".", originID ));
assert( nodes[targetID], string.format( "Tried to add an Edge to the nonexistent Node \"%s\".", targetID ));
addEdge( nodes[originID], nodes[targetID] );
end
---
-- Removes all edges leading to or originating from a node.
-- @param node - The node to remove all edges from.
--
function self:removeEdges( node )
for id, edge in pairs( edges ) do
if edge.origin == node or edge.target == node then
edges[id] = nil;
end
end
end
---
-- Updates the graph.
-- @param dt - The delta time between frames.
-- @param nodeCallback - A callback called on every node.
-- @param edgeCallback - A callback called on every edge.
--
function self:update( dt, nodeCallback, edgeCallback )
for _, edge in pairs( edges ) do
edge.origin:attractTo( edge.target );
edge.target:attractTo( edge.origin );
if edgeCallback then
edgeCallback( edge );
end
end
resetBoundaries();
for _, nodeA in pairs( nodes ) do
if not nodeA:isAnchor() then
for _, nodeB in pairs( nodes ) do
if nodeA ~= nodeB then
nodeA:repelFrom( nodeB );
end
end
nodeA:move( dt );
end
if nodeCallback then
nodeCallback( nodeA );
end
minX, maxX, minY, maxY = updateBoundaries( minX, maxX, minY, maxY, nodeA:getPosition() );
end
end
---
-- Checks if the id points to an existing node.
-- @param id - The id to check for.
--
function self:exists( id )
return nodes[id] ~= nil;
end
---
-- Draws the graph.
-- Takes two callback functions as a parameter. These will be called
-- on each edge and node in the graph and will be used to wite a custom
-- drawing function.
-- @param nodeCallback - A callback called on every node.
-- @param edgeCallback - A callback called on every edge.
--
function self:draw( nodeCallback, edgeCallback )
for _, edge in pairs( edges ) do
if not edgeCallback then break end
edgeCallback( edge );
end
for _, node in pairs( nodes ) do
if not nodeCallback then break end
nodeCallback( node );
end
end
---
-- Checks if a certain Node ID already exists.
-- @param id - The id to check for.
--
function self:hasNode( id )
return nodes[id] ~= nil;
end
---
-- Returns the node the id is pointing to.
-- @param id - The id to check for.
--
function self:getNode( id )
return nodes[id];
end
---
-- Gets a node at a certain point in the graph.
-- @param x - The x coordinate to check.
-- @param y - The y coordinate to check.
-- @param range - The range in which to check around the given coordinates.
--
function self:getNodeAt(x, y, range)
for _, node in pairs( nodes ) do
local nx, ny = node:getPosition();
if x < nx + range and x > nx - range and y < ny + range and y > ny - range then
return node;
end
end
end
---
-- Returns the graph's minimum and maxmimum x and y values.
--
function self:getBoundaries()
return minX, maxX, minY, maxY;
end
---
-- Returns the x and y coordinates of the graph's center.
--
function self:getCenter()
return ( ( maxX - minX ) * 0.5 ) + minX, ( ( maxY - minY ) * 0.5 ) + minY;
end
---
-- Turn a node into an anchor.
-- Anchored nodes have fixed positions and can't be moved by the physical
-- forces.
-- @param id - The node's id.
-- @param x - The x coordinate to anchor the node to.
-- @param y - The x coordinate to anchor the node to.
--
function self:setAnchor( id, x, y )
nodes[id]:setPosition( x, y );
nodes[id]:setAnchor( true );
end
return self;
end
---
-- Replaces the default Edge class with a custom one.
-- @param class - The custom Edge class to use.
--
function Graph.setEdgeClass( class )
Edge = class;
end
---
-- Replaces the default Node class with a custom one.
-- @param class - The custom Node class to use.
--
function Graph.setNodeClass( class )
Node = class;
end
return Graph;