initial checkin from subversion

drawLine.js

@@ -0,0 +1,81 @@
+function drawLine(fromX,fromY,toX,toY,style,pointsContainer){
+	var m_diffX;
+	var m_diffY;
+	var pX;
+	var pY;
+	var pointCnt=0; // count the points in current line
+
+	if (toX < fromX) {
+		m_diffX=fromX-toX;
+	} else {
+		m_diffX=toX-fromX;
+	}
+
+	if (toY < fromY) {
+		m_diffY=fromY-toY;
+	} else {
+		m_diffY=toY-fromY;
+	}
+
+	if (m_diffX > m_diffY) {
+		drawHorizontalLine();
+	} else {
+		drawVerticalLine();
+	}
+
+	function drawHorizontalLine(){
+		var i;
+		for (i=toX;i<=fromX;i++){
+			pX=i;
+			if (toY < fromY) {
+				pY=toY+((i-toX)*(m_diffY/m_diffX));
+			} else {
+				pY=toY-((i-toX)*(m_diffY/m_diffX));
+			}
+			drawPoint(pX,pY,style);
+		}
+		for (i=fromX;i<=toX;i++){
+			pX=i;
+			if (toY < fromY) {
+				pY=fromY-((i-fromX)*(m_diffY/m_diffX));
+			} else {
+				pY=fromY+((i-fromX)*(m_diffY/m_diffX));
+			}
+			drawPoint(pX,pY,style);
+		}
+	}
+        	
+	function drawVerticalLine(){
+		var i;
+
+		for (i=toY;i<=fromY;i++){
+			pY=i;
+			if (toX < fromX) {
+				pX=toX+((i-toY)*(m_diffX/m_diffY));
+			} else {
+				pX=toX-((i-toY)*(m_diffX/m_diffY));
+			}
+			drawPoint(pX,pY,style);
+		}
+		for (i=fromY;i<=toY;i++){
+			pY=i;
+			if (toX < fromX) {
+				pX=fromX-((i-fromY)*(m_diffX/m_diffY));
+			} else {
+				pX=fromX+((i-fromY)*(m_diffX/m_diffY));
+			}
+			drawPoint(pX,pY,style);
+		}
+	}
+	function drawPoint(x,y,style){
+		if ((pointCnt++%3)==0) { // performance, don't draw all points.
+			var point=document.createElement("div");
+			point.setAttribute("class",style);
+			point.style.left=x+"px";
+			point.style.top=y+"px";
+			
+			pointsContainer.appendChild(point);
+		}
+	}
+}
+