TIN to raster conversion

To convert a TIN to a raster, all you need to do is choose a cell size—elevation values can then be interpolated from the TIN at regularly-spaced intervals across the surface.

As you make the cell size smaller, more points are interpolated and the output raster resembles the input TIN more closely.

A TIN’s slope and aspect values can also be converted to rasters.

Left: A 2D view of a TIN layer. Right: A raster converted from the TIN. Since a raster's extent must be rectangular, areas that are not interpolated are assigned the NoData value (symbolized in gray).

Are TINs better than rasters?

No, just different. TINs and rasters both have their advantages. Some of the advantages of TINs are:

· The model has variable resolution. A TIN preserves the x,y location of input points, allowing for more detail where there is lots of surface variation and less detail where the surface doesn’t change much. A raster has the same amount of information for each part of the surface.

· You can refine the surface topography with polygon and line features, representing roads, rivers, lakes, ridgelines, or other distinctive formations.

· Because TINs are vector data, they display well at all zoom levels. Raster display degrades when you zoom in too close.

· For large-scale applications (those covering a small area in detail) or applications where display quality is very important, TINs are often a better choice.

On the other hand, rasters have their advantages, too:

· Their matrix structure makes them well-suited to analysis. Many more mathematical and statistical functions are available for rasters than for TINs.

· They demand fewer system resources. They can be created and displayed more quickly and take up less disk space.

· They are a more familiar and readily-available data type.

· For small-scale applications (those covering a large area), or applications that require statistical analysis of data, rasters are often a better choice.