24. There are two ways to associate the imported Pine Burn vectors with the Pine Burn Ecosystem. One way is to copy each vector to the Ecosystem. This is called hard linking and we've done it in previous tutorials. It works great for a few vectors but is unbelievably tedious for hundreds or thousands of them. The second way to associate vectors to Ecosystems is to dynamically link them with a Search Query.

25. Go to the Land Cover Task Mode, expand the Ecosystems category, and open the Pine Burn Ecosystem. Move to the Vector Placement section at the bottom of the General page and add a New Search Query from the Dynamic Link dropdown list.

26. This will open the Search Query window, already conveniently named Pine Burn. The default filter is set to search all database objects, which is what we want.

27. The Selected Filter page sets the criteria for searching the selected database objects. We're going to use the shapefile Attribute for Ecosystem type, ECOS, so select it from the Attribute Field dropdown list.

28. Since this is the Search Query for finding Pine Burn vectors, the ECOS Attribute value has to be equal to (=) PINE BURN.

29. To help you get your database information correct, the Database Attributes page list all objects, Attributes, and values.

30. Bring up the Database Editor and move it aside if it's hiding the Search Query. Select one of the DEMs to deselect the vectors.

31. Go to the Search Query General page and Select Items Now to test the Search Query.

32. The Pine Burn vectors will be selected in the Database Editor.

33. Open the Environment to the Ecosystems page and Remove the Pine Burn Ecosystem. This will restrict its rendering to vectors only. Confirm the operation.

34. Save the project and render a Main preview. The Pine Burn Ecosystem rendered within all Pine Burn vectors.

35. We don't need the rendered vectors anymore, so bring up the Database Editor. The PB01 vector should be the active object. Go to the Layer page and Select the PINE BURN layer. Deselect Render.

36. Save the project and render another preview.

37. The next thing we're going to do is use the species percentage Attributes to drive the relative distributions of Ecotypes within the Pine Burn Ecosystem. This is where Thematic Maps come in.

38. Bring up the Pine Burn Ecosystem Editor and turn to the Material & Foliage page. The Overstory Ecotype will be the dominant foliage species and the Understory Ecotype will be the subdominant species.

39. Edit the Overstory Ecotype to open its Editor and go to the Ecotype page.

40. The Density is currently a static value. Select Thematic Operations and Create Thematic Map.

41. A Thematic Map maps a database Attribute value to the Component value, in this case the Overstory Foliage Density. We first need to choose which database objects to use in the Database Linkage section. Select the Pine Burn Search Query from the dropdown list. If we had many Ecosystems, we'd create a Search Query that included all of them.

42. The Data page is where we assign the Attribute to the map. This is the Overstory, so choose DOM_PERCENTN from the Channel 1 dropdown list.

43. As we saw in the Search Query, the Database Attributes page gives you a quick database reference. Close out the Thematic Map Editor and the Pine Burn Overstory Ecotype Editor.

44. Repeat the process with for the Understory Ecotype. Edit Ecotype to open its Editor and go to the Ecotype page.

45. Select Thematic Operations and Create Thematic Map.

46. Go to the Database Linkage section and select the Pine Burn Search Query from the dropdown list.

47. This is the Understory, so choose SUB_PERCENTN from the Channel 1 dropdown list.

48. Open another Main Camera in the upper right view. Save the project and render a preview. An Error initializing Effects pops up because VNS needs more effects memory.

49. Open the Component Library from the Icon Toolbar. Increase the Maximum Effect Memory to 100 Mb.

50. Save the project and render another preview. Pine Burn Ecosystem placement and Ecotype Density was all accomplished with one Search Query and 2 Thematic Maps. You can use Search Queries and Thematic Maps to drive almost any Component in VNS. Read more about them in the Interactive Reference Manual.

After Thematic Maps

Before Thematic Maps

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