Create a GUI Piano

Question

Challenge

Create a GUI Keyboard with as few characters as possible.

Example

Because this was an assignment in one of my courses, I can't show the source code. However, here is a screen shot of my keyboard.

In this example, my keys were of type JButton and I used a Midi Synthesizer to produce the sound (with the default ADSR envelope values).

Rules

• You are allowed to use standard external libraries.
• Be creative with your sound. You can use 8-bit, a sitar, etc.
• For simplicities sake, you may have five keys; black and white, from C to E (the first five keys on my keyboard).
• Most importantly... showcase your work!

NOTICE: Depending on what language you choose to work with, this may be a rather large task.

This is my first question on SE Code Golf. If anything is unclear, please ask for further details.

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EDIT: The due date for this challenge will be 9/22/12. If you post an answer after this date, I will look over it regardless (and possibly +1 it).

Answer 1

Mathematica 319 259 255

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Edit: Keys now depress (as buttons) when clicked.

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This will play the grand piano notes {"C","C#","D","D#","E"}, where "C" is middle C. z[n_] plays the note.

z@n_ := EmitSound@Sound[SoundNote[n, .3, 1]]; w = {10, 300}; b = {35, 180};
Graphics[Inset[Button["", z[#[[1]]], Background -> If[#[[2]] == w, None, Black], 
ImageSize -> #〚2〛], #〚3〛] & /@ {{"C", w, {-.4, 0}}, {"D", w, {0, 0}}, {"E", w, {.4, 0}}, 
{"C#", b, {-.2, 0.31}}, {"D#", b, {.2, 0.31}}}, PlotRange -> 1]

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The keyboard can be extended to 18-keys by using fewer than double the characters:

z@n_ := EmitSound@Sound@SoundNote[n, .3, 1];
w = {"C", "D", "E", "F", "G", "A", "B", "C5", "D5", "E5", "F5"};
b = {"C#", "D#", "", "F#", "G#", "A#", "", "C#5", "D#5"}; i = ImageSize; t = Thread; 
l = List; s = Inset; m = Table; u = Button;
Graphics[Join[t[s[u @@@ t[l["", y /@ w, i -> {5, 350}]] /. y -> z, m[{90 k, 0}, {k, -5, 5}]]], 
Delete[t[s[u @@@ t[l["", y /@ b, Background -> Black, i -> {28, 212}]] /. 
  y -> z, m[{90 k + 45, 220}, {k, -5, 3}]]], {{3}, {7}}]], 
AspectRatio -> .45, PlotRange -> {{-500, 500}, {-610, 610}}, i -> {800, 430}]   

Answer 2

Web page (840/796 characters)

>>> Start playing (Internet Explorer is not supported for multiple reasons; Google Chrome and Opera work best.)

I probably could make this a bit shorter, yet it is a good start. The lower score is after replacing all occurrences of   with the character itself and removing the keyword new, the latter change breaking Google Chrome compatibility.

<style>table{border-collapse:collapse;border-width:1 0;border-style:solid;font-size:64;line-height:2}td{border-style:solid;border-width:0 1}</style><table><td colspan=3 title=0>&nbsp;<td bgcolor=black colspan=2 title=1>&nbsp;<td colspan=2 title=2>&nbsp;<td bgcolor=black colspan=2 title=3>&nbsp;<td colspan=3 title=4>&nbsp;<tr><td colspan=4 title=0>&nbsp;<td colspan=4 title=2>&nbsp;<td colspan=4 title=4>&nbsp;</table><script>for(A=[y=5];y--;){for(s=x=64e3;x--;)s+="~ "[x*(268+17*y)>>13&1];A[y]=new Audio("data:audio/wav;base64,UklGRiXuAgBXQVZFZm10IBAAAAABAAEAQB8AAEAfAAABAAgAZGF0YQHuAgCA"+btoa(s))}setInterval("for(y=5;y--;)with(A[y])volume=volume&&Math.exp(-currentTime)",99);onmousedown=function(e){if(z=e.target.title)with(A[z])play(currentTime=0,volume=1)};onmouseup=function(e){if(z=e.target.title)with(A[z])pause(volume=0)}</script>

Save this code as a text file with a name ending in .htm or .html and open it in Chrome or Opera (Safari might also work), or just open the solution's JSBin page to start playing. I reused the WAV file header from my solution to the Twinkle Twinkle Little Star code golf problem.

An important feature is that the sound diminishes as time passes. To observe this behavior, try holding down a key for a few seconds and listening to what happens.

Here is a more readable version of the code:

<style>
    table {
        border-collapse: collapse;
        border-width: 1 0;
        border-style: solid;
        font-size: 64;
        line-height: 2;
    }

    td {
        border-style: solid;
        border-width: 0 1;
    }
</style>

<table>
        <td colspan=3 title=0>&nbsp;
        <td bgcolor=black colspan=2 title=1>&nbsp;
        <td colspan=2 title=2>&nbsp;
        <td bgcolor=black colspan=2 title=3>&nbsp;
        <td colspan=3 title=4>&nbsp;
    <tr>
        <td colspan=4 title=0>&nbsp;
        <td colspan=4 title=2>&nbsp;
        <td colspan=4 title=4>&nbsp;
</table>

<script>
    for (A = [y = 5]; y--;) {

        for (s = x = 64e3; x--;)
            s += "~ "[x * (268 + 17 * y) >> 13 & 1];

        A[y] = new Audio("data:audio/wav;base64,UklGRiXuAgBXQVZFZm10IBAAAAABAAEAQB8AAEAfAAABAAgAZGF0YQHuAgCA" + btoa(s));
    }

    setInterval(function() {
        for (y = 5; y--;)
            with (A[y])
                volume = volume && Math.exp(-currentTime);
    }, 99);

    onmousedown = function(e) {
        if (z = e.target.title)
            with (A[z])
                play(currentTime = 0, volume = 1);
    };

    onmouseup = function(e) { 
        if (z = e.target.title)
            with (A[z])
                pause(volume = 0);
    };
</script>

Answer 3

Groovy: 577 (703 with whitespaces)

The first 5 notes. Others could be added easily, it's somewhat dynamic.

Damn swing. Probably with a swing lib it would be better.

Plays through JFugue.

On github: https://github.com/wpiasecki/glissando/blob/master/src/br/glissando/Piano.groovy

On groovy 2.0.2

import java.awt.event.*
class Note { def n; boolean s; def p() { new org.jfugue.Player().with {play n;close()}} }
notes=['C','C#','D','D#','E'].inject([]){ l,n -> l<< Note[n:n,s:n=~/#/]}
h=300
l=0
w=60
x=0
new groovy.swing.SwingBuilder().edt {
  frame size:[notes.size()*30+30,h], 
    show:true, 
    defaultCloseOperation:javax.swing.JFrame.EXIT_ON_CLOSE, 
    { l = layeredPane() }
  notes.each { n ->
    C=java.awt.Color
    s=n.s
    p=panel bounds:(s ? [x-15,0,w-30,h-100] : [x,0,w,h]),
      background: s ? C.BLACK : C.WHITE, 
      border: lineBorder(1, color: C.BLACK)
    p.addMouseListener({ if(it.id==MouseEvent.MOUSE_CLICKED)n.p() }as MouseListener)
    if(!s)x+=w
    l.add p,s?0:1
  }
}

Answer 4

R - 491 characters

I'm a little late but I just saw this post yesterday.

Works on a Mac, uses playRWave and packages tuneR and splancs.

a=array
x=c(7,2)
y=c(5,2)
z=c(1,1,3,3)
par(mar=rep(0,4))
plot(NA,xli=c(0,9),yli=c(0,3))
N=list(a(c(0,3,3,2,2,0,0,0,0,z,0),x),a(c(3,6,6,5,5,4,4,3,3,0,0,z,1,1,0),c(9,2)),a(c(6,6,7,7,9,9,6,0,z,0,0),x),a(c(2,4,4,2,2,z,1),y),a(c(5,7,7,5,5,z,1),y))
c=c(NA,NA,NA,1,1)
for(i in 1:5){polygon(N[[i]],c=c[i])}
h=c(261.63,293.66,329.63,277.18,311.13)
library(tuneR)
setWavPlayer("~/Library/Audio/playRwave")
repeat{P=data.frame(locator(1));play(sine(h[sapply(N,function(x)splancs::inout(P,x))],bit=16))}

Ungolfed:

par(mar=rep(0,4))
plot(NA,xlim=c(0,9),ylim=c(0,3)) #Create empty plot: due to fuzzy matching of arguments, xlim can be reduced to xli
N=list(array(c(0,3,3,2,2,0,0,0,0,1,1,3,3,0),dim=c(7,2)), #C polygon
       array(c(3,6,6,5,5,4,4,3,3,0,0,1,1,3,3,1,1,0),dim=c(9,2)), #D polygon
       array(c(6,6,7,7,9,9,6,0,1,1,3,3,0,0),dim=c(7,2)), #E polygon
       array(c(2,4,4,2,2,1,1,3,3,1),dim=(5,2)), #Db polygon
       array(c(5,7,7,5,5,1,1,3,3,1),dim=(5,2)))  #Eb polygon
c=c(NA,NA,NA,1,1) #Colors: by default 1 is "black"
for(i in 1:5){polygon(N[[i]],color=c[i])}
h=c(261.63,293.66,329.63,277.18,311.13) #Notes frequency in hertz: C4, D4, E4, Db4 and Eb4
library(tuneR)
setWavPlayer("~/Library/Audio/playRwave") #This can be change to other wav player I think
repeat{
    P=data.frame(locator(1)) #Grab coordinates of selected point
    H=h[sapply(N,function(x)splancs::inout(P,x))] #In which polygon does the selected point belong to, then map it to its ferquency
    s=sine(H,bit=16) #By default create a 1sec note at the given frequency with 44100 sampling rate
    play(s)
    }