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instrument list rendering with FT2 font.

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This commit is contained in:
Andy Sloane 2015-11-04 06:22:49 -08:00
commit f092f847f7
2 changed files with 74 additions and 16 deletions
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79
xm.js
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@ -8,10 +8,37 @@ fontimg.src = "ft2font.png";
// canvas to render patterns onto
var pat_canvas = document.createElement('canvas');
//
// for pretty-printing notes
var _note_names = ["C-", "C#", "D-", "D#", "E-", "F-", "F#", "G-", "G#", "A-", "A#", "B-"];
var f_smp = 44100; // updated by play callback, default value here
// pixel widths of each character in the proportional font
var _fontwidths = [
4, 7, 3, 6, 6, 6, 6, 5, 4, 5, 5, 5, 5, 5, 7, 7,
5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 6, 7, 7, 7, 7, 7,
4, 2, 5, 7, 7, 7, 7, 3, 4, 4, 6, 6, 3, 6, 2, 7,
6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 2, 3, 6, 6, 6, 7,
7, 7, 7, 7, 7, 7, 7, 7, 7, 2, 7, 7, 7, 8, 8, 7,
7, 7, 7, 7, 8, 7, 7, 8, 8, 8, 7, 4, 7, 4, 4, 5,
3, 6, 6, 6, 6, 6, 4, 6, 6, 2, 4, 6, 2, 8, 6, 6,
6, 6, 4, 6, 4, 6, 7, 8, 7, 6, 6, 4, 2, 4, 4, 4];
// draw FT2 proportional font text to a drawing context
// returns width rendered
function DrawText(text, dx, dy, ctx) {
var dx0 = dx;
for (var i = 0; i < text.length; i++) {
var n = text.charCodeAt(i);
var sx = (n&63)*8;
var sy = (n>>6)*10 + 7*8;
var width = _fontwidths[n];
ctx.drawImage(fontimg, sx, sy, width, 10, dx, dy, width, 10);
dx += width + 1;
}
return dx - dx0;
}
var _fontmap_notes = [8*5, 8*22, 8*28];
var _pattern_cellwidth = 16 + 4 + 8 + 4 + 8 + 16 + 4;
var _scope_width = _pattern_cellwidth - 1;
@ -176,10 +203,7 @@ function RedrawScreen() {
for (var j = 0; j < xm.nchan; j++) {
var x = _pattern_border + j * _pattern_cellwidth;
// render channel number
if (j >= 10) {
ctx.drawImage(fontimg, 8*((j/10)|0), 4*8, 4, 8, x, 1, 4, 8);
}
ctx.drawImage(fontimg, 8*(j%10), 4*8, 4, 8, x+4, 1, 4, 8);
DrawText(j, x, 1, ctx);
// volume in dB as a green bar
var vu_y = -Math.log(VU[j])*10;
@ -969,13 +993,46 @@ function loadXM(arrayBuf) {
debug.innerHTML = xm.songname;
var instrlist = document.getElementById("instruments");
var namelist = [];
for (var j = 0; j < xm.instruments.length; j++) {
var n = (j+1).toString(16);
if (j < 15) n = ' ' + n;
namelist.push(n + " " + xm.instruments[j].name);
var instrcols = ((xm.instruments.length + 7) / 8) | 0;
for (var i = 0; i < instrcols; i++) {
var canvas = document.createElement('canvas');
var ctx = canvas.getContext('2d');
var instrcolumnwidth = 8*22;
canvas.width = instrcolumnwidth;
canvas.height = 8 * 10;
ctx.fillStyle = '#000';
ctx.fillRect(0, 0, canvas.width, canvas.height);
var hasname = 0, hasdata = 0;
for (var j = 8*i; j < Math.min(8*i+8, xm.instruments.length); j++) {
var y = 10*(j - 8*i);
var n = (j+1).toString(16);
if (j < 15) n = '0' + n;
var data = xm.instruments[j].samples;
if (data) {
var len = data[0].len;
data = data[0].sampledata;
var scale = Math.ceil(len / instrcolumnwidth);
ctx.strokeStyle = '#55acff';
ctx.beginPath();
for (var k = 0; k < Math.min(len / scale, instrcolumnwidth - 20); k++) {
ctx.lineTo(k + 20, y + data[k*scale] * 4 + 4);
}
ctx.stroke();
hasdata++;
}
var name = xm.instruments[j].name;
ctx.globalCompositeOperation = 'lighten';
DrawText(n, 1, y, ctx);
if (name != '') {
DrawText(xm.instruments[j].name, 20, y, ctx);
hasname++;
}
ctx.globalCompositeOperation = 'source-over';
}
if (hasname || hasdata) {
instrlist.appendChild(canvas);
}
}
instrlist.innerHTML = namelist.join("\n");
return xm;
}