From 6134e8af601388e5fe04dbf4049e5d2279cea250 Mon Sep 17 00:00:00 2001
From: Adam Soltys <adam.soltys@pwgsc-tpsgc.gc.ca>
Date: Wed, 10 Oct 2012 17:40:42 -0700
Subject: Use javascript to generate QR code

---
 index.html |  14 +-
 qr.js      | 746 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 753 insertions(+), 7 deletions(-)
 create mode 100644 qr.js

diff --git a/index.html b/index.html
index 74f190ea..2c4a0762 100644
--- a/index.html
+++ b/index.html
@@ -4,6 +4,7 @@
     <meta charset="utf-8" />
     <title>Bitcoin Payment Calculator</title>
     <script language="javascript" type="text/javascript" src="http://code.jquery.com/jquery-1.8.1.min.js"></script>
+    <script src="qr.js"></script>
 
     <script language="javascript" type="text/javascript">
       $(function() {
@@ -12,12 +13,12 @@
         var total = 0;
         var received = 0;
         var address = getParameterByName('address');
-        var qr_url = 'https://chart.googleapis.com/chart?cht=qr&chl=bitcoin:' + address + '&chs=177x177&chld=H'
+
+        setupqr();
 
         if (address == "")
           window.location = 'index.html?address=1SoLtySab29J2tAdF2x3PosjnwWF37wEY'
 
-        $('#qr').attr('src', qr_url);
         $('#address').html(address);
 
         websocket.onopen = function() { 
@@ -71,6 +72,7 @@
           total = Math.ceil(total * 10000) / 10000;
           if (!$.isNumeric(total)) total = '';
           $('#total').html(total.toString());
+          doqr('bitcoin:' + address + '?amount=' + total.toString());
         }
       });
 
@@ -122,12 +124,10 @@
 
         <br />
 
-        <img id="qr" src="" width="300" height="300" />
-        
-        <br />
-        
         <span id="status">Waiting for Payment</span>
       </div>
-    </div>
+ <div id="qrdiv">
+    <canvas id="qrcanv"}>No Canvas Support?
+</div>   </div>
   </body>
 </html> 
diff --git a/qr.js b/qr.js
new file mode 100644
index 00000000..8cc18f69
--- /dev/null
+++ b/qr.js
@@ -0,0 +1,746 @@
+// alignment pattern
+adelta = [
+  0, 11, 15, 19, 23, 27, 31, // force 1 pat
+  16, 18, 20, 22, 24, 26, 28, 20, 22, 24, 24, 26, 28, 28, 22, 24, 24,
+  26, 26, 28, 28, 24, 24, 26, 26, 26, 28, 28, 24, 26, 26, 26, 28, 28
+  ];
+
+// version block
+vpat = [
+    0xc94, 0x5bc, 0xa99, 0x4d3, 0xbf6, 0x762, 0x847, 0x60d,
+    0x928, 0xb78, 0x45d, 0xa17, 0x532, 0x9a6, 0x683, 0x8c9,
+    0x7ec, 0xec4, 0x1e1, 0xfab, 0x08e, 0xc1a, 0x33f, 0xd75,
+    0x250, 0x9d5, 0x6f0, 0x8ba, 0x79f, 0xb0b, 0x42e, 0xa64,
+    0x541, 0xc69
+];
+
+// final format bits with mask: level << 3 | mask
+fmtword = [
+    0x77c4, 0x72f3, 0x7daa, 0x789d, 0x662f, 0x6318, 0x6c41, 0x6976,    //L
+    0x5412, 0x5125, 0x5e7c, 0x5b4b, 0x45f9, 0x40ce, 0x4f97, 0x4aa0,    //M
+    0x355f, 0x3068, 0x3f31, 0x3a06, 0x24b4, 0x2183, 0x2eda, 0x2bed,    //Q
+    0x1689, 0x13be, 0x1ce7, 0x19d0, 0x0762, 0x0255, 0x0d0c, 0x083b    //H
+];
+
+// 4 per version: number of blocks 1,2; data width; ecc width
+eccblocks = [
+    1, 0, 19, 7, 1, 0, 16, 10, 1, 0, 13, 13, 1, 0, 9, 17,
+    1, 0, 34, 10, 1, 0, 28, 16, 1, 0, 22, 22, 1, 0, 16, 28,
+    1, 0, 55, 15, 1, 0, 44, 26, 2, 0, 17, 18, 2, 0, 13, 22,
+    1, 0, 80, 20, 2, 0, 32, 18, 2, 0, 24, 26, 4, 0, 9, 16,
+    1, 0, 108, 26, 2, 0, 43, 24, 2, 2, 15, 18, 2, 2, 11, 22,
+    2, 0, 68, 18, 4, 0, 27, 16, 4, 0, 19, 24, 4, 0, 15, 28,
+    2, 0, 78, 20, 4, 0, 31, 18, 2, 4, 14, 18, 4, 1, 13, 26,
+    2, 0, 97, 24, 2, 2, 38, 22, 4, 2, 18, 22, 4, 2, 14, 26,
+    2, 0, 116, 30, 3, 2, 36, 22, 4, 4, 16, 20, 4, 4, 12, 24,
+    2, 2, 68, 18, 4, 1, 43, 26, 6, 2, 19, 24, 6, 2, 15, 28,
+    4, 0, 81, 20, 1, 4, 50, 30, 4, 4, 22, 28, 3, 8, 12, 24,
+    2, 2, 92, 24, 6, 2, 36, 22, 4, 6, 20, 26, 7, 4, 14, 28,
+    4, 0, 107, 26, 8, 1, 37, 22, 8, 4, 20, 24, 12, 4, 11, 22,
+    3, 1, 115, 30, 4, 5, 40, 24, 11, 5, 16, 20, 11, 5, 12, 24,
+    5, 1, 87, 22, 5, 5, 41, 24, 5, 7, 24, 30, 11, 7, 12, 24,
+    5, 1, 98, 24, 7, 3, 45, 28, 15, 2, 19, 24, 3, 13, 15, 30,
+    1, 5, 107, 28, 10, 1, 46, 28, 1, 15, 22, 28, 2, 17, 14, 28,
+    5, 1, 120, 30, 9, 4, 43, 26, 17, 1, 22, 28, 2, 19, 14, 28,
+    3, 4, 113, 28, 3, 11, 44, 26, 17, 4, 21, 26, 9, 16, 13, 26,
+    3, 5, 107, 28, 3, 13, 41, 26, 15, 5, 24, 30, 15, 10, 15, 28,
+    4, 4, 116, 28, 17, 0, 42, 26, 17, 6, 22, 28, 19, 6, 16, 30,
+    2, 7, 111, 28, 17, 0, 46, 28, 7, 16, 24, 30, 34, 0, 13, 24,
+    4, 5, 121, 30, 4, 14, 47, 28, 11, 14, 24, 30, 16, 14, 15, 30,
+    6, 4, 117, 30, 6, 14, 45, 28, 11, 16, 24, 30, 30, 2, 16, 30,
+    8, 4, 106, 26, 8, 13, 47, 28, 7, 22, 24, 30, 22, 13, 15, 30,
+    10, 2, 114, 28, 19, 4, 46, 28, 28, 6, 22, 28, 33, 4, 16, 30,
+    8, 4, 122, 30, 22, 3, 45, 28, 8, 26, 23, 30, 12, 28, 15, 30,
+    3, 10, 117, 30, 3, 23, 45, 28, 4, 31, 24, 30, 11, 31, 15, 30,
+    7, 7, 116, 30, 21, 7, 45, 28, 1, 37, 23, 30, 19, 26, 15, 30,
+    5, 10, 115, 30, 19, 10, 47, 28, 15, 25, 24, 30, 23, 25, 15, 30,
+    13, 3, 115, 30, 2, 29, 46, 28, 42, 1, 24, 30, 23, 28, 15, 30,
+    17, 0, 115, 30, 10, 23, 46, 28, 10, 35, 24, 30, 19, 35, 15, 30,
+    17, 1, 115, 30, 14, 21, 46, 28, 29, 19, 24, 30, 11, 46, 15, 30,
+    13, 6, 115, 30, 14, 23, 46, 28, 44, 7, 24, 30, 59, 1, 16, 30,
+    12, 7, 121, 30, 12, 26, 47, 28, 39, 14, 24, 30, 22, 41, 15, 30,
+    6, 14, 121, 30, 6, 34, 47, 28, 46, 10, 24, 30, 2, 64, 15, 30,
+    17, 4, 122, 30, 29, 14, 46, 28, 49, 10, 24, 30, 24, 46, 15, 30,
+    4, 18, 122, 30, 13, 32, 46, 28, 48, 14, 24, 30, 42, 32, 15, 30,
+    20, 4, 117, 30, 40, 7, 47, 28, 43, 22, 24, 30, 10, 67, 15, 30,
+    19, 6, 118, 30, 18, 31, 47, 28, 34, 34, 24, 30, 20, 61, 15, 30
+];
+
+// Galois field log table
+glog = [
+    0xff, 0x00, 0x01, 0x19, 0x02, 0x32, 0x1a, 0xc6, 0x03, 0xdf, 0x33, 0xee, 0x1b, 0x68, 0xc7, 0x4b,
+    0x04, 0x64, 0xe0, 0x0e, 0x34, 0x8d, 0xef, 0x81, 0x1c, 0xc1, 0x69, 0xf8, 0xc8, 0x08, 0x4c, 0x71,
+    0x05, 0x8a, 0x65, 0x2f, 0xe1, 0x24, 0x0f, 0x21, 0x35, 0x93, 0x8e, 0xda, 0xf0, 0x12, 0x82, 0x45,
+    0x1d, 0xb5, 0xc2, 0x7d, 0x6a, 0x27, 0xf9, 0xb9, 0xc9, 0x9a, 0x09, 0x78, 0x4d, 0xe4, 0x72, 0xa6,
+    0x06, 0xbf, 0x8b, 0x62, 0x66, 0xdd, 0x30, 0xfd, 0xe2, 0x98, 0x25, 0xb3, 0x10, 0x91, 0x22, 0x88,
+    0x36, 0xd0, 0x94, 0xce, 0x8f, 0x96, 0xdb, 0xbd, 0xf1, 0xd2, 0x13, 0x5c, 0x83, 0x38, 0x46, 0x40,
+    0x1e, 0x42, 0xb6, 0xa3, 0xc3, 0x48, 0x7e, 0x6e, 0x6b, 0x3a, 0x28, 0x54, 0xfa, 0x85, 0xba, 0x3d,
+    0xca, 0x5e, 0x9b, 0x9f, 0x0a, 0x15, 0x79, 0x2b, 0x4e, 0xd4, 0xe5, 0xac, 0x73, 0xf3, 0xa7, 0x57,
+    0x07, 0x70, 0xc0, 0xf7, 0x8c, 0x80, 0x63, 0x0d, 0x67, 0x4a, 0xde, 0xed, 0x31, 0xc5, 0xfe, 0x18,
+    0xe3, 0xa5, 0x99, 0x77, 0x26, 0xb8, 0xb4, 0x7c, 0x11, 0x44, 0x92, 0xd9, 0x23, 0x20, 0x89, 0x2e,
+    0x37, 0x3f, 0xd1, 0x5b, 0x95, 0xbc, 0xcf, 0xcd, 0x90, 0x87, 0x97, 0xb2, 0xdc, 0xfc, 0xbe, 0x61,
+    0xf2, 0x56, 0xd3, 0xab, 0x14, 0x2a, 0x5d, 0x9e, 0x84, 0x3c, 0x39, 0x53, 0x47, 0x6d, 0x41, 0xa2,
+    0x1f, 0x2d, 0x43, 0xd8, 0xb7, 0x7b, 0xa4, 0x76, 0xc4, 0x17, 0x49, 0xec, 0x7f, 0x0c, 0x6f, 0xf6,
+    0x6c, 0xa1, 0x3b, 0x52, 0x29, 0x9d, 0x55, 0xaa, 0xfb, 0x60, 0x86, 0xb1, 0xbb, 0xcc, 0x3e, 0x5a,
+    0xcb, 0x59, 0x5f, 0xb0, 0x9c, 0xa9, 0xa0, 0x51, 0x0b, 0xf5, 0x16, 0xeb, 0x7a, 0x75, 0x2c, 0xd7,
+    0x4f, 0xae, 0xd5, 0xe9, 0xe6, 0xe7, 0xad, 0xe8, 0x74, 0xd6, 0xf4, 0xea, 0xa8, 0x50, 0x58, 0xaf
+];
+
+// Galios field exponent table
+gexp = [
+    0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1d, 0x3a, 0x74, 0xe8, 0xcd, 0x87, 0x13, 0x26,
+    0x4c, 0x98, 0x2d, 0x5a, 0xb4, 0x75, 0xea, 0xc9, 0x8f, 0x03, 0x06, 0x0c, 0x18, 0x30, 0x60, 0xc0,
+    0x9d, 0x27, 0x4e, 0x9c, 0x25, 0x4a, 0x94, 0x35, 0x6a, 0xd4, 0xb5, 0x77, 0xee, 0xc1, 0x9f, 0x23,
+    0x46, 0x8c, 0x05, 0x0a, 0x14, 0x28, 0x50, 0xa0, 0x5d, 0xba, 0x69, 0xd2, 0xb9, 0x6f, 0xde, 0xa1,
+    0x5f, 0xbe, 0x61, 0xc2, 0x99, 0x2f, 0x5e, 0xbc, 0x65, 0xca, 0x89, 0x0f, 0x1e, 0x3c, 0x78, 0xf0,
+    0xfd, 0xe7, 0xd3, 0xbb, 0x6b, 0xd6, 0xb1, 0x7f, 0xfe, 0xe1, 0xdf, 0xa3, 0x5b, 0xb6, 0x71, 0xe2,
+    0xd9, 0xaf, 0x43, 0x86, 0x11, 0x22, 0x44, 0x88, 0x0d, 0x1a, 0x34, 0x68, 0xd0, 0xbd, 0x67, 0xce,
+    0x81, 0x1f, 0x3e, 0x7c, 0xf8, 0xed, 0xc7, 0x93, 0x3b, 0x76, 0xec, 0xc5, 0x97, 0x33, 0x66, 0xcc,
+    0x85, 0x17, 0x2e, 0x5c, 0xb8, 0x6d, 0xda, 0xa9, 0x4f, 0x9e, 0x21, 0x42, 0x84, 0x15, 0x2a, 0x54,
+    0xa8, 0x4d, 0x9a, 0x29, 0x52, 0xa4, 0x55, 0xaa, 0x49, 0x92, 0x39, 0x72, 0xe4, 0xd5, 0xb7, 0x73,
+    0xe6, 0xd1, 0xbf, 0x63, 0xc6, 0x91, 0x3f, 0x7e, 0xfc, 0xe5, 0xd7, 0xb3, 0x7b, 0xf6, 0xf1, 0xff,
+    0xe3, 0xdb, 0xab, 0x4b, 0x96, 0x31, 0x62, 0xc4, 0x95, 0x37, 0x6e, 0xdc, 0xa5, 0x57, 0xae, 0x41,
+    0x82, 0x19, 0x32, 0x64, 0xc8, 0x8d, 0x07, 0x0e, 0x1c, 0x38, 0x70, 0xe0, 0xdd, 0xa7, 0x53, 0xa6,
+    0x51, 0xa2, 0x59, 0xb2, 0x79, 0xf2, 0xf9, 0xef, 0xc3, 0x9b, 0x2b, 0x56, 0xac, 0x45, 0x8a, 0x09,
+    0x12, 0x24, 0x48, 0x90, 0x3d, 0x7a, 0xf4, 0xf5, 0xf7, 0xf3, 0xfb, 0xeb, 0xcb, 0x8b, 0x0b, 0x16,
+    0x2c, 0x58, 0xb0, 0x7d, 0xfa, 0xe9, 0xcf, 0x83, 0x1b, 0x36, 0x6c, 0xd8, 0xad, 0x47, 0x8e, 0x00
+];
+
+// Working buffers:
+// data input and ecc append, image working buffer, fixed part of image, run lengths for badness
+var strinbuf=[], eccbuf=[], qrframe=[], framask=[], rlens=[]; 
+// Control values - width is based on version, last 4 are from table.
+var version, width, neccblk1, neccblk2, datablkw, eccblkwid;
+var ecclevel = 1;
+// set bit to indicate cell in qrframe is immutable.  symmetric around diagonal
+function setmask(x, y)
+{
+    var bt;
+    if (x > y) {
+        bt = x;
+        x = y;
+        y = bt;
+    }
+    // y*y = 1+3+5...
+    bt = y;
+    bt *= y;
+    bt += y;
+    bt >>= 1;
+    bt += x;
+    framask[bt] = 1;
+}
+
+// enter alignment pattern - black to qrframe, white to mask (later black frame merged to mask)
+function putalign(x, y)
+{
+    var j;
+
+    qrframe[x + width * y] = 1;
+    for (j = -2; j < 2; j++) {
+        qrframe[(x + j) + width * (y - 2)] = 1;
+        qrframe[(x - 2) + width * (y + j + 1)] = 1;
+        qrframe[(x + 2) + width * (y + j)] = 1;
+        qrframe[(x + j + 1) + width * (y + 2)] = 1;
+    }
+    for (j = 0; j < 2; j++) {
+        setmask(x - 1, y + j);
+        setmask(x + 1, y - j);
+        setmask(x - j, y - 1);
+        setmask(x + j, y + 1);
+    }
+}
+
+//========================================================================
+// Reed Solomon error correction
+// exponentiation mod N
+function modnn(x)
+{
+    while (x >= 255) {
+        x -= 255;
+        x = (x >> 8) + (x & 255);
+    }
+    return x;
+}
+
+var genpoly = [];
+
+// Calculate and append ECC data to data block.  Block is in strinbuf, indexes to buffers given.
+function appendrs(data, dlen, ecbuf, eclen)
+{
+    var i, j, fb;
+
+    for (i = 0; i < eclen; i++)
+        strinbuf[ecbuf + i] = 0;
+    for (i = 0; i < dlen; i++) {
+        fb = glog[strinbuf[data + i] ^ strinbuf[ecbuf]];
+        if (fb != 255)     /* fb term is non-zero */
+            for (j = 1; j < eclen; j++)
+                strinbuf[ecbuf + j - 1] = strinbuf[ecbuf + j] ^ gexp[modnn(fb + genpoly[eclen - j])];
+        else
+            for( j = ecbuf ; j < ecbuf + eclen; j++ )
+                strinbuf[j] = strinbuf[j + 1];
+        strinbuf[ ecbuf + eclen - 1] = fb == 255 ? 0 : gexp[modnn(fb + genpoly[0])];
+    }
+}
+
+//========================================================================
+// Frame data insert following the path rules
+
+// check mask - since symmetrical use half.
+function ismasked(x, y)
+{
+    var bt;
+    if (x > y) {
+        bt = x;
+        x = y;
+        y = bt;
+    }
+    bt = y;
+    bt += y * y;
+    bt >>= 1;
+    bt += x;
+    return framask[bt];
+}
+
+//========================================================================
+//  Apply the selected mask out of the 8.
+function  applymask(m)
+{
+    var x, y, r3x, r3y;
+
+    switch (m) {
+    case 0:
+        for (y = 0; y < width; y++)
+            for (x = 0; x < width; x++)
+                if (!((x + y) & 1) && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+        break;
+    case 1:
+        for (y = 0; y < width; y++)
+            for (x = 0; x < width; x++)
+                if (!(y & 1) && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+        break;
+    case 2:
+        for (y = 0; y < width; y++)
+            for (r3x = 0, x = 0; x < width; x++, r3x++) {
+                if (r3x == 3)
+                    r3x = 0;
+                if (!r3x && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+            }
+        break;
+    case 3:
+        for (r3y = 0, y = 0; y < width; y++, r3y++) {
+            if (r3y == 3)
+                r3y = 0;
+            for (r3x = r3y, x = 0; x < width; x++, r3x++) {
+                if (r3x == 3)
+                    r3x = 0;
+                if (!r3x && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+            }
+        }
+        break;
+    case 4:
+        for (y = 0; y < width; y++)
+            for (r3x = 0, r3y = ((y >> 1) & 1), x = 0; x < width; x++, r3x++) {
+                if (r3x == 3) {
+                    r3x = 0;
+                    r3y = !r3y;
+                }
+                if (!r3y && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+            }
+        break;
+    case 5:
+        for (r3y = 0, y = 0; y < width; y++, r3y++) {
+            if (r3y == 3)
+                r3y = 0;
+            for (r3x = 0, x = 0; x < width; x++, r3x++) {
+                if (r3x == 3)
+                    r3x = 0;
+                if (!((x & y & 1) + !(!r3x | !r3y)) && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+            }
+        }
+        break;
+    case 6:
+        for (r3y = 0, y = 0; y < width; y++, r3y++) {
+            if (r3y == 3)
+                r3y = 0;
+            for (r3x = 0, x = 0; x < width; x++, r3x++) {
+                if (r3x == 3)
+                    r3x = 0;
+                if (!(((x & y & 1) + (r3x && (r3x == r3y))) & 1) && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+            }
+        }
+        break;
+    case 7:
+        for (r3y = 0, y = 0; y < width; y++, r3y++) {
+            if (r3y == 3)
+                r3y = 0;
+            for (r3x = 0, x = 0; x < width; x++, r3x++) {
+                if (r3x == 3)
+                    r3x = 0;
+                if (!(((r3x && (r3x == r3y)) + ((x + y) & 1)) & 1) && !ismasked(x, y))
+                    qrframe[x + y * width] ^= 1;
+            }
+        }
+        break;
+    }
+    return;
+}
+
+// Badness coefficients.
+var N1 = 3, N2 = 3, N3 = 40, N4 = 10;
+
+// Using the table of the length of each run, calculate the amount of bad image 
+// - long runs or those that look like finders; called twice, once each for X and Y
+function badruns(length)
+{
+    var i;
+    var runsbad = 0;
+    for (i = 0; i <= length; i++)
+        if (rlens[i] >= 5)
+            runsbad += N1 + rlens[i] - 5;
+    // BwBBBwB as in finder
+    for (i = 3; i < length - 1; i += 2)
+        if (rlens[i - 2] == rlens[i + 2]
+            && rlens[i + 2] == rlens[i - 1]
+            && rlens[i - 1] == rlens[i + 1]
+            && rlens[i - 1] * 3 == rlens[i]
+            // white around the black pattern? Not part of spec
+            && (rlens[i - 3] == 0 // beginning
+                || i + 3 > length  // end
+                || rlens[i - 3] * 3 >= rlens[i] * 4 || rlens[i + 3] * 3 >= rlens[i] * 4)
+           )
+            runsbad += N3;
+    return runsbad;
+}
+
+// Calculate how bad the masked image is - blocks, imbalance, runs, or finders.
+function badcheck()
+{
+    var x, y, h, b, b1;
+    var thisbad = 0;
+    var bw = 0;
+
+    // blocks of same color.
+    for (y = 0; y < width - 1; y++)
+        for (x = 0; x < width - 1; x++)
+            if ((qrframe[x + width * y] && qrframe[(x + 1) + width * y]
+                 && qrframe[x + width * (y + 1)] && qrframe[(x + 1) + width * (y + 1)]) // all black
+                || !(qrframe[x + width * y] || qrframe[(x + 1) + width * y]
+                     || qrframe[x + width * (y + 1)] || qrframe[(x + 1) + width * (y + 1)])) // all white
+                thisbad += N2;
+
+    // X runs
+    for (y = 0; y < width; y++) {
+        rlens[0] = 0;
+        for (h = b = x = 0; x < width; x++) {
+            if ((b1 = qrframe[x + width * y]) == b)
+                rlens[h]++;
+            else
+                rlens[++h] = 1;
+            b = b1;
+            bw += b ? 1 : -1;
+        }
+        thisbad += badruns(h);
+    }
+
+    // black/white imbalance
+    if (bw < 0)
+        bw = -bw;
+
+    var big = bw;
+    count = 0;
+    big += big << 2;
+    big <<= 1;
+    while (big > width * width)
+        big -= width * width, count++;
+    thisbad += count * N4;
+
+    // Y runs
+    for (x = 0; x < width; x++) {
+        rlens[0] = 0;
+        for (h = b = y = 0; y < width; y++) {
+            if ((b1 = qrframe[x + width * y]) == b)
+                rlens[h]++;
+            else
+                rlens[++h] = 1;
+            b = b1;
+        }
+        thisbad += badruns(h);
+    }
+    return thisbad;
+}
+
+function genframe(instring)
+{
+    var x, y, k, t, v, i, j, m;
+
+// find the smallest version that fits the string
+    t = instring.length;
+    version = 0;
+    do {
+        version++;
+        k = (ecclevel - 1) * 4 + (version - 1) * 16;
+        neccblk1 = eccblocks[k++];
+        neccblk2 = eccblocks[k++];
+        datablkw = eccblocks[k++];
+        eccblkwid = eccblocks[k];
+        k = datablkw * (neccblk1 + neccblk2) + neccblk2 - 3 + (version <= 9);
+        if (t <= k)
+            break;
+    } while (version < 40);
+
+// FIXME - insure that it fits insted of being truncated
+    width = 17 + 4 * version;
+
+// allocate, clear and setup data structures
+    v = datablkw + (datablkw + eccblkwid) * (neccblk1 + neccblk2) + neccblk2;
+    for( t = 0; t < v; t++ )
+        eccbuf[t] = 0;
+    strinbuf = instring.slice(0);
+
+    for( t = 0; t < width * width; t++ )
+        qrframe[t] = 0;
+
+    for( t = 0 ; t < (width * (width + 1) + 1) / 2; t++)
+        framask[t] = 0;
+
+// insert finders - black to frame, white to mask
+    for (t = 0; t < 3; t++) {
+        k = 0;
+        y = 0;
+        if (t == 1)
+            k = (width - 7);
+        if (t == 2)
+            y = (width - 7);
+        qrframe[(y + 3) + width * (k + 3)] = 1;
+        for (x = 0; x < 6; x++) {
+            qrframe[(y + x) + width * k] = 1;
+            qrframe[y + width * (k + x + 1)] = 1;
+            qrframe[(y + 6) + width * (k + x)] = 1;
+            qrframe[(y + x + 1) + width * (k + 6)] = 1;
+        }
+        for (x = 1; x < 5; x++) {
+            setmask(y + x, k + 1);
+            setmask(y + 1, k + x + 1);
+            setmask(y + 5, k + x);
+            setmask(y + x + 1, k + 5);
+        }
+        for (x = 2; x < 4; x++) {
+            qrframe[(y + x) + width * (k + 2)] = 1;
+            qrframe[(y + 2) + width * (k + x + 1)] = 1;
+            qrframe[(y + 4) + width * (k + x)] = 1;
+            qrframe[(y + x + 1) + width * (k + 4)] = 1;
+        }
+    }
+
+// alignment blocks
+    if (version > 1) {
+        t = adelta[version];
+        y = width - 7;
+        for (;;) {
+            x = width - 7;
+            while (x > t - 3) {
+                putalign(x, y);
+                if (x < t)
+                    break;
+                x -= t;
+            }
+            if (y <= t + 9)
+                break;
+            y -= t;
+            putalign(6, y);
+            putalign(y, 6);
+        }
+    }
+
+// single black
+    qrframe[8 + width * (width - 8)] = 1;
+
+// timing gap - mask only
+    for (y = 0; y < 7; y++) {
+        setmask(7, y);
+        setmask(width - 8, y);
+        setmask(7, y + width - 7);
+    }
+    for (x = 0; x < 8; x++) {
+        setmask(x, 7);
+        setmask(x + width - 8, 7);
+        setmask(x, width - 8);
+    }
+
+// reserve mask-format area
+    for (x = 0; x < 9; x++)
+        setmask(x, 8);
+    for (x = 0; x < 8; x++) {
+        setmask(x + width - 8, 8);
+        setmask(8, x);
+    }
+    for (y = 0; y < 7; y++)
+        setmask(8, y + width - 7);
+
+// timing row/col
+    for (x = 0; x < width - 14; x++)
+        if (x & 1) {
+            setmask(8 + x, 6);
+            setmask(6, 8 + x);
+        }
+        else {
+            qrframe[(8 + x) + width * 6] = 1;
+            qrframe[6 + width * (8 + x)] = 1;
+        }
+
+// version block
+    if (version > 6) {
+        t = vpat[version - 7];
+        k = 17;
+        for (x = 0; x < 6; x++)
+            for (y = 0; y < 3; y++, k--)
+                if (1 & (k > 11 ? version >> (k - 12) : t >> k)) {
+                    qrframe[(5 - x) + width * (2 - y + width - 11)] = 1;
+                    qrframe[(2 - y + width - 11) + width * (5 - x)] = 1;
+                }
+        else {
+            setmask(5 - x, 2 - y + width - 11);
+            setmask(2 - y + width - 11, 5 - x);
+        }
+    }
+
+// sync mask bits - only set above for white spaces, so add in black bits
+    for (y = 0; y < width; y++)
+        for (x = 0; x <= y; x++)
+            if (qrframe[x + width * y])
+                setmask(x, y);
+
+// convert string to bitstream
+// 8 bit data to QR-coded 8 bit data (numeric or alphanum, or kanji not supported)
+    v = strinbuf.length;
+
+// string to array
+    for( i = 0 ; i < v; i++ )
+        eccbuf[i] = strinbuf.charCodeAt(i);
+    strinbuf = eccbuf.slice(0);
+
+// calculate max string length
+    x = datablkw * (neccblk1 + neccblk2) + neccblk2;
+    if (v >= x - 2) {
+        v = x - 2;
+        if (version > 9)
+            v--;
+    }
+
+// shift and repack to insert length prefix
+    i = v;
+    if (version > 9) {
+        strinbuf[i + 2] = 0;
+        strinbuf[i + 3] = 0;
+        while (i--) {
+            t = strinbuf[i];
+            strinbuf[i + 3] |= 255 & (t << 4);
+            strinbuf[i + 2] = t >> 4;
+        }
+        strinbuf[2] |= 255 & (v << 4);
+        strinbuf[1] = v >> 4;
+        strinbuf[0] = 0x40 | (v >> 12);
+    }
+    else {
+        strinbuf[i + 1] = 0;
+        strinbuf[i + 2] = 0;
+        while (i--) {
+            t = strinbuf[i];
+            strinbuf[i + 2] |= 255 & (t << 4);
+            strinbuf[i + 1] = t >> 4;
+        }
+        strinbuf[1] |= 255 & (v << 4);
+        strinbuf[0] = 0x40 | (v >> 4);
+    }
+// fill to end with pad pattern
+    i = v + 3 - (version < 10);
+    while (i < x) {
+        strinbuf[i++] = 0xec;
+        // buffer has room    if (i == x)      break;
+        strinbuf[i++] = 0x11;
+    }
+
+// calculate and append ECC
+
+// calculate generator polynomial
+    genpoly[0] = 1;
+    for (i = 0; i < eccblkwid; i++) {
+        genpoly[i + 1] = 1;
+        for (j = i; j > 0; j--)
+            genpoly[j] = genpoly[j]
+            ? genpoly[j - 1] ^ gexp[modnn(glog[genpoly[j]] + i)] : genpoly[j - 1];
+        genpoly[0] = gexp[modnn(glog[genpoly[0]] + i)];
+    }
+    for (i = 0; i <= eccblkwid; i++)
+        genpoly[i] = glog[genpoly[i]]; // use logs for genpoly[] to save calc step
+
+// append ecc to data buffer
+    k = x;
+    y = 0;
+    for (i = 0; i < neccblk1; i++) {
+        appendrs(y, datablkw, k, eccblkwid);
+        y += datablkw;
+        k += eccblkwid;
+    }
+    for (i = 0; i < neccblk2; i++) {
+        appendrs(y, datablkw + 1, k, eccblkwid);
+        y += datablkw + 1;
+        k += eccblkwid;
+    }
+// interleave blocks
+    y = 0;
+    for (i = 0; i < datablkw; i++) {
+        for (j = 0; j < neccblk1; j++)
+            eccbuf[y++] = strinbuf[i + j * datablkw];
+        for (j = 0; j < neccblk2; j++)
+            eccbuf[y++] = strinbuf[(neccblk1 * datablkw) + i + (j * (datablkw + 1))];
+    }
+    for (j = 0; j < neccblk2; j++)
+        eccbuf[y++] = strinbuf[(neccblk1 * datablkw) + i + (j * (datablkw + 1))];
+    for (i = 0; i < eccblkwid; i++)
+        for (j = 0; j < neccblk1 + neccblk2; j++)
+            eccbuf[y++] = strinbuf[x + i + j * eccblkwid];
+    strinbuf = eccbuf;
+
+// pack bits into frame avoiding masked area.
+    x = y = width - 1;
+    k = v = 1;         // up, minus
+    /* inteleaved data and ecc codes */
+    m = (datablkw + eccblkwid) * (neccblk1 + neccblk2) + neccblk2;
+    for (i = 0; i < m; i++) {
+        t = strinbuf[i];
+        for (j = 0; j < 8; j++, t <<= 1) {
+            if (0x80 & t)
+                qrframe[x + width * y] = 1;
+            do {        // find next fill position
+                if (v)
+                    x--;
+                else {
+                    x++;
+                    if (k) {
+                        if (y != 0)
+                            y--;
+                        else {
+                            x -= 2;
+                            k = !k;
+                            if (x == 6) {
+                                x--;
+                                y = 9;
+                            }
+                        }
+                    }
+                    else {
+                        if (y != width - 1)
+                            y++;
+                        else {
+                            x -= 2;
+                            k = !k;
+                            if (x == 6) {
+                                x--;
+                                y -= 8;
+                            }
+                        }
+                    }
+                }
+                v = !v;
+            } while (ismasked(x, y));
+        }
+    }
+
+// save pre-mask copy of frame
+    strinbuf = qrframe.slice(0);
+    t = 0;           // best
+    y = 30000;         // demerit
+// for instead of while since in original arduino code
+// if an early mask was "good enough" it wouldn't try for a better one
+// since they get more complex and take longer.
+    for (k = 0; k < 8; k++) {
+        applymask(k);      // returns black-white imbalance
+        x = badcheck();
+        if (x < y) { // current mask better than previous best?
+            y = x;
+            t = k;
+        }
+        if (t == 7)
+            break;       // don't increment i to a void redoing mask
+        qrframe = strinbuf.slice(0); // reset for next pass
+    }
+    if (t != k)         // redo best mask - none good enough, last wasn't t
+        applymask(t);
+
+// add in final mask/ecclevel bytes
+    y = fmtword[t + ((ecclevel - 1) << 3)];
+    // low byte
+    for (k = 0; k < 8; k++, y >>= 1)
+        if (y & 1) {
+            qrframe[(width - 1 - k) + width * 8] = 1;
+            if (k < 6)
+                qrframe[8 + width * k] = 1;
+            else
+                qrframe[8 + width * (k + 1)] = 1;
+        }
+    // high byte
+    for (k = 0; k < 7; k++, y >>= 1)
+        if (y & 1) {
+            qrframe[8 + width * (width - 7 + k)] = 1;
+            if (k)
+                qrframe[(6 - k) + width * 8] = 1;
+            else
+                qrframe[7 + width * 8] = 1;
+        }
+
+// return image
+    return qrframe;
+}
+
+var wd, ht, qrc;
+function setupqr(){
+    wd = window.innerWidth-40;
+    ht = window.innerHeight-40;
+    mp = document.getElementById("mapcanv");
+
+    qrd = document.getElementById("qrdiv");
+    qrd.style.width = wd + "px";
+    qrd.style.height = ht + "px";
+
+    wd -= 4;
+    ht -= 80;
+
+    var elem = document.getElementById('qrcanv');
+    qrc = elem.getContext('2d');
+    qrc.canvas.width = wd;
+    qrc.canvas.height = ht;
+    qrc.fillStyle = '#eee';
+    qrc.fillRect(0,0,wd,ht);
+
+}
+
+function doqr(value) {
+    d = document;
+    ecclevel = 1;
+    qf = genframe(value);
+    qrc.lineWidth=1;
+
+    var i,j;
+    px = wd;
+    if( ht < wd )
+        px = ht;
+    px /= width+10;
+    px=Math.round(px - 0.5);
+    qrc.clearRect(0,0,wd,ht);
+    qrc.fillStyle = '#fff';
+    qrc.fillRect(0,0,px*(width+8),px*(width+8));
+    qrc.fillStyle = '#000';
+    for( i = 0; i < width; i++ )
+        for( j = 0; j < width; j++ )
+            if( qf[j*width+i] )
+                qrc.fillRect(px*(4+i),px*(4+j),px,px)
+}
-- 
cgit v1.2.3