71. Let's say you want to make some changes to your terrain, but something more painterly and permanent than a Terraffector or Area Terraffector. That's where the new DEM Painter comes in. We could jump right to the DEM Painter window by selecting the DEM in the Database Editor and clicking the Paint button. Instead, let's go the long way round with the Edit button.

72. Here's the new DEM Editor. The Elevations page lists the elevation of all vertices in the DEM.

73. Zoom in a couple of notches and click on the cliff top to the left.

74. The DEM Editor takes you right to the nearest terrain grid vertex.

75. Change the value here and at the surrounding 8 vertices to 75 meters.

76. Go to the File page and Save DEM to File.

77. Confirm that you understand the ramifications of your choice; there is no undo once you overwrite the DEM file.

78. The realtime TG Camera view will refresh with your changes.

79. Return the camera to its default position and save the project.

80. Select DEM Painter and you'll see a grayscale plan view of the Groovy DEM.

81. We're just going to smooth out a few of those cliff tops, so Show Brushes and select the soft edged one at the bottom of the left column.

82. Show Tools and select Smooth.

83. Click and drag along the hard edges to soften them up.

84. Switch to the Smear tool and drag some ridges out from highlands into the canyons.

85. Save the DEM to disk .

86. Once again, WCS will give you options for overwriting the existing DEM or creating a new one. Choose Overwrite.

87. The realtime view will reflect the painted changes.

88. If you're curious to see what it looks like, save the project and run a preview render.

89. One of the reasons that WCS can render large terrain in a reasonable amount of time is that it renders the terrain surface differently than traditional 3D programs render 3D surfaces. To see this, we'll need to get a closer look at the terrain.

90. Open the planimetric camera and switch back to a realtime view.

91. Open View Preferences, change the view Width to 10 meters.

92. Render a preview. Here we see terrain polygons rendered at a Fractal Depth of 0.

93. According to the Database Editor Extent page for the DEM, each Grid Cell is 3.3 meters on a side.

94. At a Maximum Fractal Depth of 0, the default, each grid cell is rendered as 2 polygons, which we can see clearly in the preview render.

95. Open the Terrain Parameter Editor and increase the Maximum Fractal Depth to 1.

96. Close out the DEM Painter and DEM Editor and open another planimetric camera view in the upper right quad.

97. Render a preview.

98. With each increase in Fractal Depth value, each polygon is further divided into 4 polygons.

99. Vertices are shifted vertically according to the Vertical Displacement percentage and horizontally if Horizontal Displacement is checked. Increase the Maximum Fractal Depth to 7, the highest value.

100. Render a preview.

101. Each original polygon in the left camera view has now been rendered as more than 16,000 polygons, each only a few centimeters on a side. The increase in apparent detail is significant. The key word here is apparent. We have not increased actual terrain detail. The original grid polygon edges are still there, we've just made them less obvious.

102. Now that we know what Fractal Depth is, let's talk briefly about the 3 methods available for rendering. In the Terrain Parameter Editor, the default Fractal Depth method is Variable. This renders near polygons at a higher Fractal Depth, where we can see them, and decreases Fractal Depth with distance. Variable Fractal Depth is a good choice for still images. Constant Fractal Depth renders the same Fractal Depth everywhere, which will significantly increase render time. Think of Fractal Maps as Variable Fractal Depth for animations. When Fractal Depth Maps are created, WCS maps near and far polygons along active camera paths.

103. While we're talking about terrain detail, let's look at bump mapping. New to WCS 6, bump mapping can be applied to the terrain via a Ground Effect. It can increase the realism of the terrain surface while hiding unsightly polygons.

104. Go to the Land Cover Task Mode and open the Ground Effect Editor to the Material page. At the bottom of the Selected Material Ground Overlay section are two bump map parameters, Bump Intensity and Bump Map Texture.

105. Click the Texture Operations button beside Bump Map Texture and Create Texture.

106. The default texture is Fractal Noise with a Size of 1 meter along the X, Y, and Z axes.

107. Render a left view preview and let's see what it looks like. Even with just the default texture, polygon edges are less visible and the terrain looks more like ground.

108. Increase the Bump Intensity to 500%.

109. Render the right view preview. Polygons are almost gone entirely.

110. Go back to the Terrain Parameter Editor and change the Maximum Fractal Depth to 0

111. Render a left view preview. The much lower Fractal Depth preview rendered faster and we still can't see any polygons.

112. Go back to the Ground Editor and disable the Bump Map Texture.

113. Render the right view preview. Amazing what a little bump can do for your terrain.

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