"Accurately" calculate BPM (Beats Per Minute)?

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9 years ago

I may not have much to say (and this question may be broad-ish), but can you accurately calculate BPM in RBX.lua? Doing some "deep" web search was not helpful as there were not many tutorials on calculating BPM. Whilst one site may have a tutorial, tempotap.com seems to have on what I was looking for. It works, but it is not very accurate on Lua

001--Javascript code taken from tempotap.com
002--[[
003    var startTime = null;
004        var currentBeats = 0;
005 
006 
007 
008        /*
009        $(window).keypress(function(event) {
010            var spaceBarKey = 32;
011            var lowerXKey = 120;
012            var upperXKey = 88;
013 
014            var result = true;
015 
016            var keyCode = event.which;
017 
018            //if (!(event.which == 115 && event.ctrlKey)) return true;
019                //alert(keyCode);
020 
021            if (keyCode == spaceBarKey) {
022                handleNewBeat();
023                result = false;
024            } else if ((keyCode == lowerXKey) || (keyCode == upperXKey)) {
025                handleBeat();
026                result = false;
027            }
028 
029            if (!result) {
030                event.preventDefault();
031            }
032            return result;
033        });
034        */
035 
036        function handleNewBeat() {
037            if (currentBeats == 0) {
038                startTime = new Date();
039            }
040            currentBeats++;
041            updateBpm();
042        }
043 
044        function handleReset() {
045            startTime = null;
046            currentBeats = 0;
047            updateBpm();
048        }
049 
050        function updateBpm() {
051            var value = '&nbsp;';
052            var title = 'BPM';
053            if (currentBeats > 1) {
054                var now = new Date();
055                var miliseconds = now.getTime() - startTime.getTime();
056                var minutes = miliseconds / 60000.0;
057                var bpm = (currentBeats - 1) / minutes;
058                value = bpm.toFixed(2);
059                title = 'BPM (' + currentBeats.toString() + ' beats)';
060            } else if (currentBeats == 1) {
061                title = 'BPM (1 beat)';
062            }
063            $('#divBpm').html(value); 
064            $('#divBpmTitle').html(title);
065        }
066 
067        shortcut.add(" ",function() {
068            handleNewBeat();
069        });
070        shortcut.add("x",function() {
071            handleReset();
072        });
073        shortcut.add("Shift+x",function() {
074            handleReset();
075        });
076]]
077 
078--Javascript code 'translated' into Lua, but it is not accurate enough
079 
080local mouse = game.Players.LocalPlayer:GetMouse()
081 
082local starttime = nil
083local currentBeat = 0
084 
085function handleNewBeat()
086    if currentBeat == 0 then
087        starttime = time()
088    end
089    currentBeat = currentBeat + 1 --original Javascript code is 'currentBeat++'
090    updateBPM()
091end
092 
093function updateBPM()
094    if currentBeat > 1 then
095        now = tick()
096        miliseconds = now % 100000
097        minute = miliseconds % 60
098        bpm = (currentBeat - 1) * minute --/ 4 --I have done different operators, but none seem to be accurate either
099        --script.Parent.Text = "BPM: "..bpm
100        print("BPM: ", bpm)
101    end
102end
103 
104mouse.KeyDown:connect(function(key)
105    if key == "t" then
106        handleNewBeat()
107    end
108end)
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"Accurately" calculate BPM (Beats Per Minute)?

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