Pitney Bowes MapInfo Professional - Manual (Page 72)

Reordering Map Layers
Map layers display in the order that they are listed in the Layer Control window, with the bottom layer
drawn first and the top layer (which is always the Cosmetic Layer) drawn last. It is important to order
your layers correctly.
For example, you have a layer of customer points and a layer of census tracts. If the layers are incorrectly
ordered in the Map window, MapInfo Professional might draw the customer points first and then display
the census tract layer second. Your points would be obscured by the census tract layer. You can reorder
how layers are displayed in a Map window two ways.
• For more about layers, see Reordering Layers, Changing the Order of Contiguous Layers and Changing
the Order of Random Layers topics in the Help System.
Layer order is also important when you use the Select button. The Select tool selects objects from the
topmost Selectable layer. If you have several objects at the same location, it is difficult to select the exact
one you want. You can reorder your layers in Layer Control so that the layer you want to select from is
the new topmost layer.
MapInfo Professional does not allow you to control the front-to-back ordering of objects within a single
map layer. If you are editing a table, and you draw a line on top of a circle, the line might appear in front
of or behind the circle; you cannot control whether it is in the front or the back. You can, however, control
the front-to-back ordering of objects in a Layout window.
If you need to control the ordering of objects (for example, you need to make sure that your lines
display on top of your regions), put the different object types in separate layers. Put your line Note:
objects in one table, and put your region objects in another table. Then use the Layer Control
window to order the layers.
• For more information, see Removing a Layer from the Map and Changing how a Layer Displays on
the Map in the Help System.
Setting the Zoom Layering
Sometimes you want a map layer to display only at certain zoom levels. Zoom Layering controls the
display of a map layer so that it displays only when the map's zoom level falls within a preset distance.
For example, you have a layer of streets and a layer of postal code boundaries. When you zoom out
past 10 or so miles, the streets look like a black smudge in the window. This is because the zoom (window
width) is too wide to show detailed street maps. Use Zoom Layering to tell MapInfo Professional to display
MapInfo Professional 12.5 72
Working with Layers in the Layer Control