Arrow Tools

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Arrow Tools

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Use the Arrow tools to drag objects, to select and deselect objects, and to perform other arrow actions.

Drag Objects: Dragging objects with the Arrow tool is at the heart of Sketchpad’s Dynamic Geometry capabilities. You drag objects to investigate mathematical relationships, to explore variations, to test conjectures, and to discover new properties.

Select and Deselect Objects: Many of Sketchpad’s menu commands act on selected objects. By selecting objects, you focus the software’s attention on one or a handful of the many objects that make up a sketch. For example, you’ll use selection to identify the objects to be transformed by the Transform menu or the objects to be measured by the Measure menu.

Perform Other Arrow Actions: In addition to dragging and selecting, use the Arrow tool for several other purposes, such as constructing points of intersection, pressing action buttons, and resizing coordinate systems, function plots, pictures, and loci.

There are three Arrow tools: the Translate Arrow tool, the Rotate Arrow tool, and the Dilate Arrow tool. These three tools behave identically when you use them to select objects; it’s only their dragging behavior that differs.

To change from one Arrow tool to another, press and hold the icon in the Toolbox until a menu pops out. Choose a different variation of the tool from this menu to make it the active Arrow tool.

If an Arrow tool is already active, you can switch to a different Arrow tool by holding the Shift key and pressing either the right or left arrow key.

Translate Arrow Tool

Drag selected objects with the Translate Arrow tool to translate them — that is, to slide them by any distance in any direction without turning or changing size or shape. This is the default Arrow tool.

Use the Translate Arrow tool to select and deselect objects, press action buttons, and construct points of intersection just like the other Selection Arrow tools.

If you want to construct a translated image of an object instead of translating the original object itself, use the Transform | Translate command.

When you translate an independent point that determines a single straight object, hold the Shift key to constrain the straight object to be horizontal, vertical, or at a multiple of 15°.

Rotate Arrow Tool

Drag selected objects with the Rotate Arrow tool to rotate them — that is, to turn them around a center point by any desired angle without changing their distance from the center, their size, or their shape.

The center point used for rotation is the point you marked most recently using the Transform | Mark Center command. If you haven’t marked a center point, Sketchpad automatically marks the point nearest to the center of the screen.

You can also mark a point as the center of rotation by double-clicking it with an Arrow tool.

Use the Rotate Arrow tool to select and deselect objects, press action buttons, and construct points of intersection just like the other Selection Arrow tools.

If you want to construct a rotated image of an object instead of rotating the original object itself, use the Transform | Rotate command.

Dilate Arrow Tool

Drag selected objects with this tool to dilate them — that is, to stretch or shrink them farther from or closer to a center point by any desired amount without changing their direction from the center or their shape.

The center point used for dilation is the point you marked most recently using the Transform | Mark Center command. If you haven’t marked a center point, Sketchpad automatically marks the point nearest to the center of the screen.

You can also mark a point as the center of dilation by double-clicking it with an Arrow tool.

Use the Dilate Arrow tool to select and deselect objects, press action buttons, and construct points of intersection just like the other Selection Arrow tools. You can also use the Dilate Arrow tool to zoom in and out on a sketch.

If you want to construct a dilated image of an object instead of dilating the original object itself, use the Transform | Dilate command.