Adding rectangle tool

js/drawingtools/Rectangle.js

@@ -0,0 +1,125 @@
+/*
+ * @provide pskl.drawingtools.Rectangle
+ *
+ * @require pskl.utils
+ */
+(function() {
+	var ns = $.namespace("pskl.drawingtools");
+
+	ns.Rectangle = function() {
+		this.toolId = "tool-rectangle"
+		
+		// Rectangle's first point coordinates (set in applyToolAt)
+		this.startCol = null;
+		this.startRow = null;
+		// Rectangle's second point coordinates (changing dynamically in moveToolAt)
+		this.endCol = null;
+		this.endRow = null;
+		
+		this.canvasOverlay = null;
+	};
+
+	pskl.utils.inherit(ns.Rectangle, ns.BaseTool);
+	
+	/**
+	 * @override
+	 */
+	ns.Rectangle.prototype.applyToolAt = function(col, row, frame, color, canvas, dpi) {
+		this.startCol = col;
+		this.startRow = row;
+		
+		// The fake canvas where we will draw the preview of the rectangle:
+		this.canvasOverlay = this.createCanvasOverlay(canvas);
+		// Drawing the first point of the rectangle in the fake overlay canvas:
+		this.drawPixelInCanvas(col, row, this.canvasOverlay, color, dpi);
+	};
+
+	ns.Rectangle.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.getRectanglePixels_(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) {
+				color = "rgba(255, 255, 255, 0.6)";
+			}			
+			this.drawPixelInCanvas(strokePoints[i].col, strokePoints[i].row, this.canvasOverlay, color, dpi);
+		}
+	};
+
+	/**
+	 * @override
+	 */
+	ns.Rectangle.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.getRectanglePixels_(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();
+	};
+
+	/**
+	 * Get an array of pixels representing the rectangle.
+	 *
+	 * @private
+	 */
+	ns.Rectangle.prototype.getRectanglePixels_ = function(x0, x1, y0, y1) {
+		
+		var pixels = [];
+		var swap;
+		
+		if(x0 > x1) {
+			swap = x0;
+			x0 = x1;
+			x1 = swap;
+		}
+		if(y0 > y1) {
+			swap = y0;
+			y0 = y1;
+			y1 = swap;
+		}
+
+		// Creating horizontal sides of the rectangle:
+		for(var x = x0; x <= x1; x++) {
+			pixels.push({"col": x, "row": y0});
+			pixels.push({"col": x, "row": y1});
+		}
+
+		// Creating vertical sides of the rectangle:
+		for(var y = y0; y <= y1; y++) {
+			pixels.push({"col": x0, "row": y});
+			pixels.push({"col": x1, "row": y});	
+		}
+		
+		return pixels;
+     };
+
+})();