SequencerView.js

// Written by Jürgen Moßgraber - mossgrabers.de
// (c) 2014
// Licensed under GPLv3 - http://www.gnu.org/licenses/gpl.html

var NUM_ROWS = 128;
var NUM_COLS = 8;
var NUM_DISPLAY_ROWS = 8;
var NUM_DISPLAY_COLS = 8;
var START_KEY = 32;

function SequencerView ()
{
	this.offsetX = 0;
	this.offsetY = START_KEY;
	this.step    = -1;
	
	this.data = [];
	for (var y = 0; y < NUM_ROWS; y++)
		this.data[y] = initArray (false, NUM_COLS);
	
	this.clip = host.createCursorClip (NUM_COLS, NUM_ROWS);
	this.lengthInBeatTime = 16;
	this.clip.setStepSize (this.lengthInBeatTime);
	
	this.clip.addPlayingStepObserver (doObject (this, function (step)
	{
		this.step = step;
	}));
	
	this.clip.addStepDataObserver (doObject (this, function (column, row, state)
	{
		this.data[column][row] = state;
	}));
	
	this.clip.scrollToKey (START_KEY);
	this.clip.scrollToStep (0);
}
SequencerView.prototype = new BaseView ();

SequencerView.prototype.updateArrows = function ()
{
	this.canScrollUp = this.offsetY + NUM_DISPLAY_ROWS <= NUM_ROWS - NUM_DISPLAY_ROWS;
	this.canScrollDown = this.offsetY - NUM_DISPLAY_ROWS >= 0;
	this.canScrollLeft = this.offsetX > 0;
	BaseView.prototype.updateArrows.call (this);
};

SequencerView.prototype.onActivate = function ()
{
	BaseView.prototype.onActivate.call (this);

	push.setButton (PUSH_BUTTON_NOTE, PUSH_BUTTON_STATE_HI);
	push.setButton (PUSH_BUTTON_SESSION, PUSH_BUTTON_STATE_ON);
	for (var i = 0; i < 8; i++)
		trackBank.getTrack (i).getClipLauncherSlots ().setIndication (false);
	for (var i = PUSH_BUTTON_SCENE1; i <= PUSH_BUTTON_SCENE8; i++)
		push.setButton (i, i % 2 == 0 ? PUSH_COLOR_SCENE_GREEN : PUSH_COLOR_BLACK);
};

SequencerView.prototype.usesButton = function (buttonID)
{
	switch (buttonID)
	{
		case PUSH_BUTTON_NEW:
		case PUSH_BUTTON_CLIP:
		case PUSH_BUTTON_SELECT:
		case PUSH_BUTTON_ADD_EFFECT:
		case PUSH_BUTTON_ADD_TRACK:
		case PUSH_BUTTON_REPEAT:
		case PUSH_BUTTON_ACCENT:
		case PUSH_BUTTON_USER_MODE:
		case PUSH_BUTTON_DUPLICATE:
			return false;
	}
	return true;
};

SequencerView.prototype.onScene = function (index)
{
	var button = 7 - index;
	if (button % 2 != 0)
		return;
	this.lengthInBeatTime = Math.pow (0.5, button / 2);
	this.clip.setStepSize (this.lengthInBeatTime);
};

SequencerView.prototype.onGrid = function (note, velocity)
{
	if (velocity == 0)
		return;
	var index = note - 36;
	var x = index % 8;
	var y = Math.floor (index / 8);
	this.clip.toggleStep (x, this.offsetY + y, velocity);
};

SequencerView.prototype.onLeft = function ()
{
	var newOffset = this.offsetX - NUM_DISPLAY_COLS;
	if (newOffset < 0)
		this.offsetX = 0;
	else
	{
		this.offsetX = newOffset;
		this.clip.scrollStepsPageBackwards ();
	}
	this.updateArrows ();
};

SequencerView.prototype.onRight = function ()
{
	this.offsetX = this.offsetX + NUM_DISPLAY_COLS;
	this.clip.scrollStepsPageForward ();
	this.updateArrows ();
};

SequencerView.prototype.onUp = function ()
{
	this.offsetY = Math.min (NUM_ROWS - NUM_DISPLAY_ROWS, this.offsetY + NUM_DISPLAY_ROWS);
	this.updateArrows ();
};

SequencerView.prototype.onDown = function ()
{
	this.offsetY = Math.max (0, this.offsetY - NUM_DISPLAY_ROWS);
	this.updateArrows ();
};

SequencerView.prototype.drawGrid = function ()
{
	var hiStep = this.isInXRange (this.step) ? this.step % NUM_DISPLAY_COLS : -1;
	for (var x = 0; x < NUM_DISPLAY_COLS; x++)
	{
		for (var y = 0; y < NUM_DISPLAY_ROWS; y++)
		{
			var isSet = this.data[x][this.offsetY + y];
			var hilite = x == hiStep;
			push.pads.lightEx (x, y, isSet ? (hilite ? PUSH_COLOR_ORANGE_HI : PUSH_COLOR_RED_HI) : hilite ? PUSH_COLOR_GREEN_HI : PUSH_COLOR_BLACK);
		}
	}
};

SequencerView.prototype.isInXRange = function (x)
{
	return x >= this.offsetX && x < this.offsetX + NUM_DISPLAY_COLS;
};