EDITING How to make your own!

esf Laboratory for Applied GIS 2 Orthophoto background Green is County boundary Yellow is soils layer (NRCS) This is called the “Coincident Line” problem

esf Laboratory for Applied GIS 3 File types Shape files FC Coverages –ArcINFO format –PC ArcInfo format Rasters of various kinds TINs (Triangulated Irregular Networks) Networks Can edit Cannot edit in ArcMap Can’t even open in ArcMap* nope Yup * Open in ArcView 3.3 & save as a shapefile

esf Laboratory for Applied GIS 4 Editing Steps 1.Load only the data needed for editing into ArcMap 2.Click on the “Selection” tab at the bottom of the TOC (demo) 3.Make sure only the layer to be edited is selected 4.This gets around the Booby Trap of having the wrong layer in the Target window!

Setup Load Edit toolbar Set Task Set Target esf Laboratory for Applied GIS 5

6 Set Snapping Snapping environment –Select “snapping” from Edit dropdown –Priority of snapping is the order of the layers (drag ‘em’). –In this case the mills will be snapped to the road’s edges. –Set snapping Tolerance (how close for jump) –Edit/options

esf Laboratory for Applied GIS 7 Snapping tricks Press “T” will show you what the current snapping tolerance is… If you need to change the snapping tolerance often then load the interactive snap tolerance toll to any tool bar –Rt clk blank spot on menu bar, scroll down to the bottome of the list that appears and click cutomize. Click the Command tab and then Edit and scroll down to the tool –Drag it to any tool bar (Edit, perhaps) –Clicking on the tool allows you to draw a circle that is the snapping tolerance you need.

esf Laboratory for Applied GIS 8 Setting Snapping Stuff Pixels or map units No, No, No Distance between vertices Number of vertices to be deleted when you screw up – and you will when using stream mode! Tip says what you are snapped to

esf Laboratory for Applied GIS 9 Sketch Construction Tools: Sketch tool Use the Sketch tool to create point features and digitize the vertices of line or polygon features. After you finish the sketch, ArcMap adds the final segment, and the sketch turns into a feature.

esf Laboratory for Applied GIS 10 Sketch Construction Tools: ArcTool The Arc tool helps you create a segment that is a parametric (true) curve. Instead of being made of numerous vertices, a parametric curve has only two vertices as endpoints.

esf Laboratory for Applied GIS 11 Sketch Construction Tools - midpoint The Midpoint tool lets you define the location of the next vertex by clicking two points; the new vertex is placed at the midpoint of the line between these points.

esf Laboratory for Applied GIS 12 Midpoint tool?

esf Laboratory for Applied GIS 13 Sketch Construction Tools The Trace tool helps you create segments that Follow along parallel to an existing segment.

esf Laboratory for Applied GIS 14 Trace tool Traces along an existing line features (instead of typing the angle and length of each segment.) select the parcel features before you can start tracing the road casing feature. The Trace tool only follows selected features.

esf Laboratory for Applied GIS 15 Split Poly Tool Use the “Cut Polygon Features” task Why –Makes a perfect match between polys when Split – every time and… –Select poly to split with the Edit Tool Use pencil tool to draw a line through the poly where you want it split Rt click anywhere to finish the job

IMPORTANT STUFF 3Ts –TARGET –TASK –TOOL 3Ss –Snapping What –Snapping distance –Selection esf Laboratory for Applied GIS 16