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Surfaces GISC 6382 UT-Dallas 4/3/2008 RBAn ArcScene Example for the UTD Area (as used in GIS Fundamentals)Creating the UTD ArcScene ExampleObtaining Elevation Data : Create a raster GRID using USGS DataCreate TIN from North Texas GIS Consortium Points and Breaklines dataLab/Homework ExerciseSurfaces GISC 6382 UT-Dallas 4/3/2008 RBAn ArcScene Example for the UTD Area (as used in GIS Fundamentals)The data for this demo is available in: P:\briggs\g6381\av3dArcScene is basically a 3-D version of ArcMap, and can be launched from the Start menu, or from within ArcCatalog or ArcMap if the 3-D extension has been loaded. (Extensions are loaded thru Tools/Extensions. You generally then need to also open specialized toolbars for these extensions via View/Toolbars .)Go to Start/Programs/ArcGIS/ and select ArcScene—the ArcScene application opens.Go to File/open, navigate to P:\briggs\g6381\av3d and load utdsurface9.sxdThe top graphic is a 3-D TIN with elevation shade, “draped” with a road file and digital otho (40% transparency).--use the Navigate tool (1st--space ship) to rotate the view and change your perspective--use the 3-D Zoom In/Out tool (2nd) to zoom in (drag across screen)e.g look at lakes in lower left (Cambell west of Coit), or WaterView Parkway --click Globe icon to return to full extent after zoomingselect the Identity (info) tool ( blue “i”)--click on the map (away from roads) and you are given its elevation, slope, aspectTurn on the TIN display layer (last layer in TofC): this shows the construction of the TIN surface.(it’s actually a copy of the utdtin layer displayed in a different manner—see step 3 below)TINs can only be displayed with ArScene and 3-D Analyst.The lower graphic is a 2-D contour line and raster representations of the same elevation surface.Consists of a shapefile of contour lines, on top of an elevation raster (in ESRI’s GRID format)--turn off contours: raster depicts surface features quite well ---select magnifier tool: zoom in to show rasters.Right click Raster Elevation GRID in Tof C, select Properties, and click Source tabNote: Cell size: 48.12 feet 48.12(cell size)x166(rows)=approx 8,000ft Data is for 8,000 by 12,000 “tile” 48.12(cell size)x249(cols)=approx 12,000ft Contours (in shapefile format) and GRIDs can be displayed in regular 2-D ArcMap. However, to do analyses with GRIDs you need the Spatial Analyst extension. Creating the UTD ArcScene Example1. Open Blank ArcScene documentGo to Start/Programs/ArcGIS/ and select ArcScene—the ArcScene application opens.A toolbar beginning with 3-D Analyst button should be available. If not, go to View/Toolbars and load it.Click the Add Data icon (big black +), navigate to P:\briggs\g6381\av3dand select utdtin--a map appears; it is in 3-D but there isn’t much relief in North Dallas!2. Modify Vertical Exageration for the Scene In the ArcScene Tof C, right click on the Scene Layer title (at the very top) and select Scene Properties--The Scene Properties dialog opens: here you can set properties to apply to all layers in the scene --Under General tab, click Calculate from Extent on vertical exaggeration line, then click Apply--north Dallas turns into the Rockies--type “6” into the vertical exaggeration box, then click Apply button, then OK button 3. Show TIN construction Double click (or right click) utdtin entry in ArcScene TofC --the Layer Properties dialog opens: select the Symbology tabThe Show box (on left side) controls which features of the TIN are displayedThe right box controls the symbology used for the display of a particular featureFaces with same symbol is selected, which is not very useful! --click the Add button below the Show box: the Add Renderer dialog lists more features to displayClick on Edges with same symbol to select it, then click Add button in Add Renderer dialogClick on Nodes with same symbol to select it, then click Add button in Add Renderer dialogClick on Face Elevation with graduated color ramp to select it, then click Add button 1Click Dismiss button to close Add Renderer dialog--in the Show box, place check marks next to Elevation, Edges and Nodes,(not Faces) --click Apply button, then the OK button to close the Layer Properties dialogYou can now see the TIN triangles from which the elevation surface is constructed. 4. Show slope or aspect (direction of slope)again, double click (or right click) utdtin entry in ArcScene TofC to open the Layer Properties dialogagain, click the Add button below the Show box to open the Add Renderer dialogClick Face slope with graduated color ramp then click Add button in Add Renderer dialogClick Face aspect with grad. color ramp to select it, then click Add button in Add Renderer dialog Click Dismiss button to close Add Renderer dialogin the Show box, place check marks next to Slope, Edges, & Nodes and remove all other checks --click Apply button, then the OK button to close the Layer Properties dialog--the slope of each TIN is now color coded--to display aspect, place check against Aspect rather than Slope in the Show box Return things to the original by placing check against Elevation in the Show box and removing all others.5. Add Roads for orientationClick the Add Data icon (big black +), navigate to P:\briggs\g6381\av3d, and select utdcnli.shp--roads display below the surface ‘cos they have no elevationDouble click utdcnli.shp in Tof C—Layer Properties dialog opens. Select Base Heights tab.In Height box, click Obtain heights form surface and be sure utdtin shows in the windowIn Offset box, type in 2 (this raises roads 2 units above the surface (prevents overlaying)Click Apply button, then OK button to close.Use the Zoom tool (magnifier glass) to zoom to the upper right corner. Note the stream channel by Floyd Rd and the ditch between the two carriageways of Waterview Parkway6. Add Digital Ortho Image Click the Add Data icon (big black +), navigate to P:\briggs\g6381\av3d, and select 24967042.jpg--again, image displays below the surface ‘cos it has no elevationDouble click 24967042.jpg in Tof C—Layer Properties dialog opens. Select Base Heights tab:In Height box, click Obtain heights from surface Click down arrow in box below and select utdtin In Offset box, type in 1 (this raises ortho 1 unit above the surface (prevents overlaying))Click Apply button, then OK button to close.The digital ortho image has been “draped” over the surface—but you can’t see


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