SURFdriver Quick Start - Page 3 We're now going to use the Y images as a template for creating the Y object. We do this by contouring the objects in the image, using the tools in the tool palette. A contour is a series of vertices surrounding an object which defines its shape. We create these contours using the tools described below. The Magic Wand tool is the easiest to use. Select this tool, and try clicking in the center of one of the blue circles, and a ring of vertices will appear. Press backspace or delete to erase the points you just added. To make the vertices more dense, or to change the capture threshold, click on the triangle to the right, and increase the number in the dialog box, then click again. The Pencil tool works like a pencil. Just trace the outline of the object, and when you let go of the mouse, vertices are placed in along the line you drew. You can also add points one at a time using this tool. Note that you must add the vertices in a clockwise direction! There are also tools you can use to change your contour once you have created it. The Move Vertex tool allows you to move vertices you have already created. Just select this tool, click on the point you want to move, then drag it to its new location, and let go. You can invoke this tool without even selecting it by holding down the control or command key at any time. The Insert Vertex tool lets you insert a new point between two existing points. Just select this tool, and click on the line where you want the new point to be. The Delete Vertex tool lets you delete one or more points. Click and drag this tool to select an area of points to delete. The Magnify tool lets zoom into the image to make more accurate changes. The Demagnify tool zooms out. The Scroll tool lets you move around the image while you are zoomed. Just select this tool, then click and drag in the main window.