ANY-maze Help > The ANY-maze reference > The Protocol page > The elements of a protocol > Apparatus > Apparatus > Setting up a piece of apparatus > Apparatus map grids

Apparatus map grids

You can't use a grid to define the borders of your apparatus - you must use one or more drawing objects to do this; see below for more details.

Introduction

It's quite common to want to divide apparatus up in a regular way, perhaps into a number of equal sized squares or into a series of concentric circles. Although this can be done using the normal apparatus map drawing objects like lines and rectangles, ANY-maze includes a simpler method - grids.

Apart from simplifying the process of drawing an apparatus map, grids have another advantage - they're defined in centimetres. Thus, if you want to divide your apparatus into say, 10cm squares, you simply have to specify a 10cm grid.

The fact that you specify a grid in centimetres means that ANY-maze needs to know the scale of your apparatus before it can correctly display a grid. Therefore, you should first set the scale - see Using the ruler line to define the scale of the apparatus map - and then add a grid. If you add the grid first, it's not a problem - it'll just be resized when you set the scale.

Adding a grid

To add a grid to an apparatus map, click the Grid settings button which is shown in the ribbon bar when an apparatus element is selected. This will open the Grid Settings Window, where you can specify the grid, or grids you want.

There are three types of grids available, and you can use them in any combination.

Square grid

As you'd expect a square grid divides a map into equal sized squares. In common with all grids, a square grid will by default be centred within the borders of your apparatus map. However, you can control exactly what 'centred' means. There are two choices; the grid can either have a square in the centre of the apparatus map or a grid crossing - see figure 1.

Figure 1. The upper box is divided up using a square grid with a grid square at the centre, while the lower one has a grid crossing at the centre.

Concentric grid

A concentric grid is a series of concentric circles. The grid 'size' is the amount by which the radius of the circles increases. For example, a 20cm concentric grid will have an inner circle with a radius of 20cm, the next circle will have a radius of 40cm, then 60cm, and so on. Concentric grids can be very useful in water-mazes. By default, the grid will be centred on the centre of your apparatus map.

Radial grid

Radial grids are usually used in conjunction with concentric grids, but they don't have to be. This type of grid draws 'spokes' outwards from a centre point. The grid 'size' is the angle between one spoke and the next. Of course, you will probably want to use an exact divisor of 360° such as 90°, 45° or 30° so that the grid is a regular size. A 90° radial grid offers an easy way to divide a water-maze, for example, into four quadrants.

As mentioned above, you can use more than one type of grid at the same time. If you do this, then all the grids will have the same origin. Therefore, using a concentric grid with a 90° radial grid will cause the radial grid to exactly divide the concentric grid's circles.

You might be tempted to use a grid to define your apparatus in its entirety without using any drawing objects; however, this won't work. For example, if you have a water-maze with a 2m diameter and you define a 1m concentric grid, the first circle will exactly fit around the water-maze and so you might think that this circle could be used to define the apparatus borders. In fact, ANY-maze requires that you always use drawing objects to define the borders of your apparatus, whereas you can only use grids to divide up the inside of the apparatus map.

You will probably notice that grids extend outside the borders of your apparatus and cover the entire video image - this is normal, but only occurs while you're drawing the apparatus map. Thereafter, ANY-maze will restrict the grid to the inside of the apparatus.

Editing a grid

You can return to the Grid Settings Window at any time to alter any aspect of your grid(s). You can also use the mouse to physically reposition a grid within your apparatus map by simply dragging it around. If you do this and then want the grid to go back to its default position of being centred within the apparatus map, simply double click one of the grid lines.

Removing a grid

To remove a grid, just switch it off in the Grid Settings Window.

ANY-maze help topic T0124