| iTool User's Guide: Working with Surfaces |

## Manipulating Surface Displays

The iSurface tool provides options for manipulating surface data. You can rotate as well as scale surfaces. These manipulations are described in the following sections.

### Rotating a Surface

Rotation tools are provided in the iSurface tool to make it easier to see all aspects of a 3-D surface visualization. Surfaces can be rotated freely or along an axis with the mouse, and they can be rotated in fixed or arbitrary increments from the Operations menu.

To rotate a surface freely or along an axis with the mouse:

1. Select the surface in the iSurface window.

2. Click Rotate on the Manipulator toolbar. The rotation sphere is displayed around the surface.

Figure 11-8: Surface with Rotation Sphere Displayed

Figure 11-8: Surface with Rotation Sphere Displayed

- To rotate the surface freely, position the mouse pointer over the surface so that it changes to a free rotation pointer . Click and drag to rotate the surface in the desired direction.

- To rotate the surface along an axis, position the mouse pointer over an axis so that it changes to an axis rotation pointer . Click and drag to rotate the surface along the axis in the desired direction.

To rotate a surface in 90û increments left or right from the Operations menu:

1. Select the surface in the iTool window.

2. Select Operations Rotate Rotate Left or Operations Rotate Rotate Right.

To rotate a surface an arbitrary number of degrees from the Operations menu:

1. Select the surface in the iTool window.

2. Select Operations Rotate Rotate by Angle.

3. In the Rotate Angle dialog, enter the desired number of degrees to rotate the surface.

For more information, see Rotation.

### Scaling a Surface

Surfaces can be scaled freely, or scaling can be constrained to one or more dimensions.

To scale a surface freely:

1. Select the surface in the iTool window.

2. Position the mouse pointer over a side of the data set bounding box so that it changes to an unconstrained scaling pointer .

3. Click and drag to scale all points of the surface in the desired direction.

To constrain scaling of a surface:

1. Select the surface in the iTool window.

2. Position the mouse pointer over an axis "whisker" to scale along only one axis, or over a corner of the bounding box for multi-axis scaling.

Figure 11-9: Constrained Single-Axis (left) and Multi-Axis (right) Scaling

Figure 11-9: Constrained Single-Axis (left) and Multi-Axis (right) Scaling

3. Click and drag to scale in the desired direction.

For more information, see Scaling.

### Adding Annotations

Annotations can be added to label or describe surface visualizations displayed in the iSurface tool.

The following types of annotations can be added to iSurface displays:

Table 11-1: Types of Surface Annotations

Table 11-1: Types of Surface Annotations
Plot Annotation Type | Description
--- | ---
Text | Single lines or multiple lines of text can be added to a visualization to provide a label or description.
Line | Straight line annotations can be added to a visualization to link labels to objects or to identify an object.
Rectangle | Rectangular annotations can be added to a visualization to identify rectangular areas.
Oval | Oval annotations can be added to a visualization to identify elliptical areas.
Polygon | Polygon annotations can be added to a visualization to identify areas bounded by a polygon.
Freehand | Freehand annotations can be added to a visualization to identify an area.

For more information on creating and using annotations, see Adding Annotations.

### View Zoom

View Zoom allows you to zoom in or out on a specific area of the surface display area. To zoom in or out in View Zoom mode click Zoom on the toolbar. For more information on working with View Zoom, see Zooming.

### Canvas Zoom

Canvas Zoom allows you to increase or decrease the magnification of the entire display canvas (which may contain multiple views, depending on the layout) by a specified percentage. Canvas Zoom is available by selecting the pull-down percentage list from the top of the tool just under the Help menu. For more information on working with Canvas Zoom, see Zooming.

### Extracting a Line Profile

To extract a line profile of part of your surface visualization in an iPlot window:

1. Click on the Line Profile icon on the iSurface window toolbar.

2. Use the mouse to position the jagged-edge line profile tool over the place which you wish your line profile to begin.

3. Drag to the ending point of your line profile.

4. The profile plot appears in an iPlot window.

Once a line profile has been drawn, it will remain until deleted. The line may be translated (or its endpoints moved individually) by switching back to the arrows. If it is translated or edited, the profile plot will automatically update.

If you dismiss your Plot Profile window and wish to have it back again, from your iSurface window, with the line selected, choose Operations Plot Profile and the Plot Profile window will reappear.

IDL Online Help (March 01, 2006)