Grids

A grid divides an area into cells of a size you choose, and counts how many fit: whole cells, and cells cut by the edge. Use it to count tiles or paving slabs on a patio, solar panels on a roof, plots in a field, or planting positions in a bed. You can move and turn the grid on the map, and the count follows, so you can find the position that fits the most.

Add a grid#

1. Click the polygon to open its panel.
2. Press grid_onGrid. The panel closes and the grid panel opens on the right.
3. Press addAdd a grid.

The first grid runs along the area's longest side, with a corner of the grid at the start of that side. Its cells are square, about a tenth of the area across, rounded to a tidy size in your unit (such as 2 m, 5 m or 25 ft). Change it from there.

Grids are for areas: the button is there for polygons, not for lines or holes. You need to be able to edit the project to add or change a grid; everyone who opens the project sees its lines on the map.

Read the count#

At the top of the grid panel:

• the big number is Whole cells: cells entirely inside the area;
• below it, how many more cells the edge cuts through;
• Cell size (width × height) and Cell area.

A cell that a hole covers does not count; a cell that a hole's edge crosses counts as cut.

If the cells are very small for the area, the panel says Too many cells to count at this size. Make the cells larger.. And when there would be too many lines to see, they are not drawn and the panel says so; the count still works.

Set the cell size#

Under Cells, type the Width and Height in your distance unit, then press Enter or click elsewhere. Use the size of the thing you are counting, plus any joint or gap: a 60 × 60 cm tile with a 5 mm joint is a 0.605 m cell. The smallest cell is 1 cm.

The width runs along the line from the grid's move handle to its turn handle (see below), and the height across it.

Move and turn the grid#

While the grid panel is open, two handles sit on the map:

• the move handle open_with, on a corner of the grid: drag it to slide the whole grid. It jumps onto a corner or a side of the area when it comes close, so a row of cells can start exactly at a wall or a kerb;
• the turn handle rotate_right, at the end of the line from the move handle: drag it round to turn the grid about the move handle. It lines up with the area's main sides (square to them, too) and with north when it comes within a couple of degrees.

The count changes as you drag. Each drag is saved when you let go, as one step that undo Undo takes back.

Under Position in the panel you can also:

• type the Rotation in degrees, turning clockwise. At 0 the width runs east–west;
• press straightenLine up with the longest side to put the grid back along the longest side, keeping its cell size.

Show, hide or remove the grid#

• Show on the map hides the grid's lines or shows them again. The grid keeps its settings while hidden. Hiding Polygons in visibility Show/Hide elements hides the grids too.
• grid_offRemove grid takes the grid off the area.

The grid later on#

The grid is saved with the polygon, for everyone on the project, and travels with it in .mmp files. A duplicate keeps it, and so do both halves of a split.

The grid stays where you placed it on the map. If you move or rotate the polygon afterwards, the cells do not follow: place the grid again with the handles, or press straightenLine up with the longest side.