Creating a Buffer - MapInfo_Pro - 2023

To buffer objects:

1. Select the objects that you want to buffer. Make sure there is an editable layer in the Map window. The output buffered objects will be placed in that layer.
   Note: There are certain table variables that you need to be aware of that will determine the aggregation method used in joining the table of buffers to data associated with the original objects. See Table Variables for this information.
2. On the SPATIAL tab, in the Edit group, click Buffer. The Buffer Objects dialog box displays.
3. Select appropriate buffer radius, segments per circle, distance type calculation to use, and buffer method as described.
   • Radius - The radius is the width of the buffer you want to create around the object you selected. The Value and the From Column radio buttons give you different ways to specify that width.
   • Value - Type a value into this field if the radius of the buffer you want to create is a specific distance. Examples might include 10 feet, 20 kilometers, 50 chains.
   • From Column - Select this radio button if the buffer you want to create is specified in a particular column or is to be calculated by an expression. Then select the column or choose Expression from the drop-down list.
   • If you select Expression, the Expression dialog box displays. Specify the expression you want MapInfo Pro to use to calculate the buffer radius and click OK to return to the Buffer Objects dialog box.
   • Units - Select the units for the buffer from this drop-down list. Options include: inches, links, feet, US Survey feet, yards, rods, chains, miles, nautical miles, millimeters, centimeters, meters, kilometers.
   • Smoothness - Type the number of segments per circle that determines the resolution of the curves in the buffer polygon. You can enter a number between 3 and 100. The default value is 12 segments per circle. If making adjustments, a value of 24 yields good results.
   • The more segments you enter, the smoother the curve. The fewer segments, the more jagged the curve. More segments produce a smoother curve; fewer segments make a more jagged curve.
     Note: Creating a buffer is time consuming. The higher the smoothness (more segments), the longer it takes to create a buffer.
   • One buffer of all objects - Select this option to create one buffer for all of the objects you have selected. For example, if you are buffering Pennsylvania, New York and New Hampshire, one buffer will be created for all three of these objects.
   • One buffer for each object - Select this option to create one buffer for each object you have selected. For example, if you are buffering Pennsylvania, New York and New Hampshire, each object will have a separate buffer.
   • Buffer Width Distance using Spherical - Select this option if you want the buffer to take into account the curvature of the Earth. Using this method, MapInfo Pro converts the data to Latitude/Longitude and then creates a mathematical calculation of the buffer. You cannot use this method for non-Earth projections.
   • Buffer Width Distance using Cartesian - Select this option if you want the buffer to be calculated as if the map is on a flat plane. Cartesian coordinates are a pair of numbers, (x, y), defining the position of a point in a two-dimensional space by its perpendicular projection onto two axes which are at right angles to each other. If you are using a Latitude/Longitude projection, this option is disabled.
4. When you have completed your entries and selections in this dialog box, click the Next button. The standard Data Aggregation dialog box displays.
   Note: If the editable layer is the Cosmetic layer, the Data Aggregation dialog box will not display because there is no data in the layer to aggregate. The OK button displays in place of the Next button. Click OK to begin the buffer operation.
5. Highlight each of the columns to complete the fields in this dialog box.
   • No Change - Select this option to keep the value for the selected column in the target row unchanged. This option only displays when you combine objects into a target object.
   • Blank - Select this option to store blank values in the selected column(s). To store blank values in all displayed columns, select the No Data check box. Only choose the Blank option to blank out individual columns.
   • Value - Select this option to store the value that displays in the edit field in the new row. When you select this option, enter an appropriate value in the field.
   • No Data - Check this check box if you want no data aggregated to any column.
6. After setting the appropriate data aggregation parameters, click OK. MapInfo Pro calculates the buffer according to the parameters you set and creates the new objects in the editable layer. The original objects remain unchanged. Once MapInfo Pro has created the buffer region, it puts it in the editable layer.