The surface object represents a single 2D grid (raster) in 3D and is one of the most important object types in GeoScene3D. Surfaces are used to model terrain and any other surface below or above ground. Surfaces may be geologic layer interfaces, interpolated geophysical surfaces, water tables, etc. In the Project Settings dialog one surface in the project can be selected as terrain model. The surface may be colored using a colors scale or single color. It is also possible to drape a bitmap onto the surface.
A surface object visualizes a single grid. Multiple grids in a time series can be visualized and animated using the Surface Time Series Object.
Surfaces may be edited with the Grid Editor Tool (Editor Version)
Grid Format Performance
Although multiple grid file formats are supported the best performance is obtained by using the binary Surfer grid format (version 7). For large grids the difference in performance is significant. This is because only the section of the grid within the current scene extent is read from the source file into memory. GeoScene3D was tested with a 3.3GB grid that was read and/or updated in only a few seconds!
Graphics Performance
Surface objects have very complex geometry and therefore have considerable impact on performance. This is very important to have in mind when importing grids. The more nodes in the grid the more impact on performance! Performance varies enormously from machine to machine depending on the graphics card in the machine, therefore it is also difficult to recommend grid sizes.
Example: On a nVIDIA GeForce FX Go5200 with 64 MB of RAM. A project with 3 to 4 grids sized 250 by 250 nodes performed well. This is a rather small card (in 2006). Modern cards with 128 or 256 MB of RAM performes much better. See surface performance.
Name: Object name as seen in the Object Manager
Visible: Show/Hide the object
Not Editable: When checked the object can not be edited and will not be included in the editable objects drop down list
Transparent Blank Area Margin: When grids contain blank areas the surface is completely transparent in the blank areas. To avoid graphical problems along the blank areas an extra transparent margin is added to the transparent areas.
Quality Distance: This parameter indicates at which distance the terrain quality can be degraded to favor speed. The distance is expressed in absolute coordinates units. The surface area closer than this distance is shown in full geometry and according to Quality Style.
Advanced Performance…: Opens settings dialog for advanced surface performance improvements.
Remark: General purpose remark
Grid Dataset: Grid Dataset for the surface geometry.
Export To File…: Saves a copy of the grid to a file in various formats
Properties
Opacity: Degree of opacity. 1=fully opaque, 0=fully transparent (enabled when Blending Mode = Transparency)
Color: The surface is single color. Press the Color button to select a color
Advanced: Shows the advanced Material Editor
Apply Transparent Color: If checked the selected color will be transparent. Press the Transparent Color button to select a transparent color. Note: Works best if the bitmap has relatively large continuous areas with the specified color.
Surface Bitmap Mode
Selection of the type and resolution of surface bitmap
Type: Color, color scale, from map, bitmap dataset, attribute grid color, symbols.
Resolution [pixels]: Bitmap resolution in pixels. Large bitmaps consumes large amounts of system resources. Therefore, in general bitmaps should not be larger than strictly necessary.
Color
See “Properties” above
Color Scale:
Color Scale: Press the Color Scale button to Import and/or edit the color scale using the Color Scale Editor.
Show Legend: Show legend form.
Smooth (slow): The smooth factor is used for color scale only and is used to smooth the color scale to produce sharper discrete levels. When the smooth factor is larger than one, each node value is represented by more than one pixel. Example: if smooth factor is 2 each cell in the grid is divided into 2 * 2 = 4 pixels. The higher the smooth factor the sharper color levels. Note, this settings should be used with care. The higher the smooth factor the longer it takes to generate a color scaled bitmap.
From Map
Map: The bitmap selected from Map is draped on the 3D surface using the settings from the map.
Bitmap Dataset
Select: Select a bitmap dataset from the Dataset Manager.
Clear: Clear any selected bitmap dataset.
Edit: Edit any selected bitmap dataset in the Dataset Editor.
Graphic Dataset that can be draped onto the surface (optional)
When the Shading check box is checked the surface is shaded. With shading the shape of the surface is much easier to see.
Brightness: Brightness of the shades. If set to max the shades are not visible.
Contrast: Contrast of shades
Sub Sampling: Smoothness of shades. Shades has the maximum detail at the lowest level of sub sampling
Direction Vector
The shades are calculated from a virtual light source at an infinite distance. The beams from the light source have this direction. The default position of the light source is in the north-west.
If the grid is the result of an interpolation performed in GeoScene3D this tab will contain information regarding the interpolation settings. If the settings are found you may run a new interpolation based on the same data and settings that was used to produce the current grid. Note: The data used to produce the grid may not be available any more.
Surfaces added to the Attribute Grids list will be available as attribute grid in the Material tab.
Available Surfaces: Available surfaces in the project that may be used as attribute grid
Add: Adds surface to list
Remove: Removes selected surface from list
The Profile tab contains settings used when the surface is shown in profile windows.
Line
Visible: Show line when checked
Width: Line width in pixels
Style: Line style
Line Color Mode
Single Color: Use the color specified in the Material tab
Same as 3D: Use the color from 3D as specified in the Material tab. However, if bitmap dataset or bitmap from map is used in 3D, the single color is used.