Difference between LAYERS and SURFACES

Layers are found in the CAD program and are used to assist you in controlling the various types of information in the drawing. It allows you to control the colour of the objects, the line type of the objects, and most importantly the visibility of the objects.

Example : Layer TREE might be set to the colour GREEN and line type CONTINUOUS. We could FREEZE that layer and the trees drawn on this layer would be temporarily made invisible in the drawing. THAWING the layer would reinstate the Layer TREE. Thus you have full control of the visibility, colour, and line type of that layer.

Surfaces on the other hand are used in QuickSurf and do not control the colour, line type or visibility of objects as do layers. Surfaces are created from a group of 3 dimensional point data where for each (X,Y) there is only one possible Z value.

The Surface is a mathematical description of this group of points, where every point is joined to it's adjacent points by a continuous, flexible model. This surface can be used to depict many different things; Existing Topography, Proposed Topography, Geologic Structures, Chemical concentrations, Pressure Gradient Maps, Slope Maps and much more.

Surfaces can also have more complicated information associated to it known as Break Lines. Break lines assist in the definition of the surface by controlling whether the space between adjacent points are valleys or hills in relation to the points around them. Surfaces can be used to generate TIN's, GRIDS, CONTOURS and much more!