Using Surfaces as Images

When a surface is opened in a surface window, Manifold computes the view to present based on the settings in View - Display Options for that surface. The views presented in the surface window are the results of computations and usually represent greater information than simply color coding the values in the Surface. To capture the view presented, we can Copy the surface and Paste As an image. We can then use the resulting image as desired.

 

To Capture a Surface as an Image

 

1. Open the surface in a surface window by double-clicking on the surface in the project pane.

2. Use View - Display Options to specify the appearance of the surface.

3. At any time thereafter, Copy the surface component in the project pane and Paste As an image. The resulting image will capture the appearance of the surface component using the current display options.

 

Example

 

See the Surface Display Options topic for an example of importing the Montara Mountain USGS high resolution SDTS - DEM as a surface.

 

images\sc_surf_displayopts_01.gif

 

Importing the file creates a surface component and a terrain, as well as some comments components.

 

images\sc_surf_asimage_01.gif

 

We can double-click open the surface and set the View - Display Options to show Height with Shading and Autocontrast as shown in the Surface Display Options topic

 

images\sc_surf_asimage_02.gif

 

In the project pane we can right click on the surface and choose Copy. We can then right click into the project pane and choose Paste As - Image.

 

images\sc_surf_asimage_02.gif

 

A new image appears in the projection pane. It is a grayscale image capturing the view of the surface seen in the surface window.

 

images\sc_surf_asimage_03.gif

 

If we open the resulting image we can see it is the same as the surface window view. However, we now have a real image. We can paint into it, we can covert it into an RGB or RGBa image and we can use it as a layer within a map. We could use the original surface as a layer in a map too, but converting it into an image allows us a wider range of editing effects such as partial transparency applied to individual pixels as can be done with RGBa images.

 

For example, we could create an image from a surface and then use it within a map as seen below. The map was created using DTED Level 2 and VMAP Level 2 sample data downloaded from the NIMA web site.

 

images\sc_surf_asimage_04.gif

 

Create the image above using the following steps:

 

1. Import a surface from DTED Level 2 sample file for Kileen, Texas.

2. Import the VMAP Level 2 file for the same area, checking hydrography and roads layers.

3. Open the surface and set display options to use Height, Shading and Autocontrast.

4. Copy the surface and paste as an image.

5. The VMAP Level 2 importer creates hydro and roads maps. Open the hydro map.

6. Drag and drop the image into the hydro map. Place it at the bottom of the map layer stack.

7. Drag and drop the roads layer into the hydro map.

8. Format the water areas in the hydro map in blue colors. Set their opacity to 50%.

9. Format labels and hydro lines to taste.

 

Note that importing a surface usually results in a georeferenced surface, since almost all formats used for surfaces are geographically aware formats. When a georeferenced surface is copied and pasted as an image, the resulting image is also georeferenced. It may be immediately combined with drawing layers in maps without further georeferencing.