balaam’s gists

balaam / reverseTable.lua

Created July 16, 2012 10:59

Reverse an ipairs table in Lua (not clever O(n) could be O(n/2) with swapping)

	--
	-- Reverses an ipairs table
	--
	--local r = ReverseTable({'a', 'b', 'c'})
	--for k, v in ipairs(r) do
	-- print(k, v)
	--end
	--
	--
	function ReverseTable(t)

balaam / combinations.lua

Created August 14, 2012 20:55

Get all combinations of items in a table

	function AllCombinations(list, stop)
	stop = stop or #list

	if stop == 0 then
	return list
	end


	local collect = {}
	for k, v in pairs(list) do

balaam / subcombinations.lua

Created August 14, 2012 21:01

Get all combinations and all sub combinations in a table (I'm sure there's a term for this!)

	function AllCombinations(list, stop)
	stop = stop or #list

	if stop == 0 then
	return list
	end


	local collect = {}
	for k, v in pairs(list) do

balaam / TypeHolder.cpp

Created August 21, 2012 09:51

Storing type information about an object with out templating the outer object or having inhertance on the parent object. Exploring some code that uses a similar method for C++ reflect system

	#include "cstdio"

	// No type information
	class ClassMeta
	{
	class Holder
	{
	public:
	virtual void* GetPtr() const { return NULL; }
	protected:

balaam / WrapZeroOne.lua

Created August 22, 2012 14:56

Wrap a number in the range 0-1. e.g. 1.3 becomes 0.3

	function WrapZeroOne(value)
	value = value - math.floor(value)
	if value < 0 then
	x = x + 1
	end
	return value
	end

balaam / wrap

Created December 16, 2012 13:01

Cyclic array access Lua vs C-languages

	--
	-- In C style languages you can cyclically access elements of an array using the modulus operator
	--
	-- Lua-style psuedo code:
	--
	-- array = {'a', 'b', 'c', 'd'};
	-- i = 0;
	-- while true do
	-- print(array[i % array.count()]);
	-- i++;

balaam / JRPG - Stats

Created September 17, 2013 20:40

http://www.godpatterns.com/2013/09/how-to-make-rpg-stats.html

	Stats = {}
	Stats.__index = Stats
	function Stats:Create(stats)
	local this =
	{
	mBase = {},
	mModifiers = {}
	}

	-- Shallow copy

balaam / gist:8415427

Created January 14, 2014 09:12

C# Oddment Table as described here: http://www.godpatterns.com/2006/01/oddment-table.html

	public class OddmentTable<T>
	{
	// Allows comparison of generic types.
	//See: http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=193203&SiteID=1
	private static readonly IEqualityComparer<T> comparer =
	EqualityComparer<T>.Default;
	protected List<Entry> entries = new List<Entry>();
	protected int oddment = 0;
	protected Random random;

balaam / JRPG - Levels

Created February 5, 2014 11:59

Example code for a levelling up system in a JRPG. As explained on my blog http://www.godpatterns.com and upcoming book: www.howtomakeanrpg.com

	function nextLevel(level)
	local exponent = 1.5
	local baseXP = 1000
	return math.floor(baseXP * (level ^ exponent))
	end

	Stats = {}
	Stats.__index = Stats
	function Stats:Create(stats)
	local this =

balaam / Lerp with out params

Created February 14, 2014 02:23

	public static float LerpF( float value, float in0, float in1, float out0, float out1 )
	{
	float normed = (value - in0) / (in1 - in0);
	float result = out0 + (normed * (out1 - out0));
	return result;
	}

Daniel Schuller balaam