Copying and Pasting Data Points

Data points can be copied and pasted within graphics views.

Copy selected data points to the Windows clipboard

1. Select EDIT \ COPY (or <Ctrl+C>).

2. These may then be pasted (EDIT \ PASTE or <Ctrl+V>) in the following ways:

   • Select a set of target data points and pasting - this pastes the positions of the copied points into the target points, in the order that they have been selected (the number of target points must equal the number of points copied).

   • Select an active curve (using the Left Mouse button in a graphics view) and paste - this inserts the copied positions as new data points in the curve. The order of the new data points within the curve is determined by inserting each point into the region of the original curve that is closest to it. Note that the curve must be fitted in order for this to have any effect.

   • The positions of the data points may be pasted as text (for example, into spreadsheet cells or a text editor).

The first two methods can be used to create a guaranteed intersection point between two curves. When pasting a new data point into a curve, the curve flashes briefly to let the user know that the operation has been successful.

Copying and pasting individual data point coordinate values, groups of coordinate values and so forth can be done within the Data Points spreadsheet grid.

Combined Editing Approach

The three different forms of editing point positions are useful in different ways, for example:

• Drag points with the mouse to get them in roughly the right place (the Snap to Grid facility may be useful here).

• Nudge points using arrow keys for refining curves (improving fairness )

• Use direct numerical entry when precise positions are required. Alternatively, copy <Ctrl+C> and paste <Ctrl+V> cells to and from other places within the grid, or from an external spreadsheet-type grid

• Use copying and pasting of data points to ensure accurate connections between different curves (see Copying and Pasting Data Points). This is particularly important for ensuring that a surface can be built successfully.

The correspondence and visual feedback that exists between the graphical views and Data Points grid is designed to aid interchanging between editing techniques freely, for more efficient working.

It is a good strategy to work with small groups of curves visible at the same time. Editing curves in isolation increases the danger of producing sets of curves that are individually perfectly fair, but that will never all lie together in a fair surface. Observing patterns of within the curvature distribution of neighbouring curves is useful in this respect:

Figure 3:52. A group of curves and their curvature tufts.

Displaying too a large number of curves can create confusion whilst editing.