piskel/js/drawingtools/Stroke.js
2012-09-03 01:34:11 +02:00

106 lines
3.7 KiB
JavaScript

/*
* @provide pskl.drawingtools.Stroke
*
* @require pskl.utils
*/
(function() {
var ns = $.namespace("pskl.drawingtools");
ns.Stroke = function() {
this.toolId = "tool-stroke"
// Stroke's first point coordinates (set in applyToolAt)
this.startCol = null;
this.startRow = null;
// Stroke's second point coordinates (changing dynamically in moveToolAt)
this.endCol = null;
this.endRow = null;
this.canvasOverlay = null;
};
pskl.utils.inherit(ns.Stroke, ns.BaseTool);
/**
* @override
*/
ns.Stroke.prototype.applyToolAt = function(col, row, frame, color, canvas, dpi) {
this.startCol = col;
this.startRow = row;
// When drawing a stroke we don't change the model instantly, since the
// user can move his cursor to change the stroke direction and length
// dynamically. Instead we draw the (preview) stroke in a fake canvas that
// overlay the drawing canvas.
// We wait for the releaseToolAt callback to impact both the
// frame model and canvas rendering.
// The fake canvas where we will draw the preview of the stroke:
this.canvasOverlay = this.createCanvasOverlay(canvas);
// Drawing the first point of the stroke in the fake overlay canvas:
this.drawPixelInCanvas(col, row, this.canvasOverlay, color, dpi);
};
ns.Stroke.prototype.moveToolAt = function(col, row, frame, color, canvas, dpi) {
this.endCol = col;
this.endRow = row;
// When the user moussemove (before releasing), we dynamically compute the
// pixel to draw the line and draw this line in the overlay canvas:
var strokePoints = this.getLinePixels_(this.startCol, this.endCol, this.startRow, this.endRow);
// Clean overlay canvas:
this.canvasOverlay.getContext("2d").clearRect(
0, 0, this.canvasOverlay.width, this.canvasOverlay.height);
// Drawing current stroke:
for(var i = 0; i< strokePoints.length; i++) {
if(color == Constants.TRANSPARENT_COLOR) {
// When mousemoving the stroke tool, we draw in the canvas overlay above the drawing canvas.
// If the stroke color is transparent, we won't be
// able to see it during the movement.
// We set it to a semi-opaque white during the tool mousemove allowing to see colors below the stroke.
// When the stroke tool will be released, It will draw a transparent stroke,
// eg deleting the equivalent of a stroke.
color = "rgba(255, 255, 255, 0.6)";
}
this.drawPixelInCanvas(strokePoints[i].col, strokePoints[i].row, this.canvasOverlay, color, dpi);
}
};
/**
* @override
*/
ns.Stroke.prototype.releaseToolAt = function(col, row, frame, color, canvas, dpi) {
this.endCol = col;
this.endRow = row;
// If the stroke tool is released outside of the canvas, we cancel the stroke:
// TODO: Mutualize this check in common method
if(col < 0 || row < 0 || col > frame.length || row > frame[0].length) {
this.removeCanvasOverlays();
return;
}
// The user released the tool to draw a line. We will compute the pixel coordinate, impact
// the model and draw them in the drawing canvas (not the fake overlay anymore)
var strokePoints = this.getLinePixels_(this.startCol, this.endCol, this.startRow, this.endRow);
for(var i = 0; i< strokePoints.length; i++) {
// Change model:
frame[strokePoints[i].col][strokePoints[i].row] = color;
// Draw in canvas:
// TODO: Remove that when we have the centralized redraw loop
this.drawPixelInCanvas(strokePoints[i].col, strokePoints[i].row, canvas, color, dpi);
}
// For now, we are done with the stroke tool and don't need an overlay anymore:
this.removeCanvasOverlays();
// TODO: Create a afterRelease event hook or out that deep in the model
$.publish(Events.FRAMESHEET_UPDATED);
};
})();