Apple's U.S. Patent No. 8,487,889 for "Virtual drafting tools" details an intuitive computer-aided design and drafting user interface, with on-screen tools that can be manipulated via a multitouch display,
The patent notes current CAD programs and other drafting applications, whether operating in two- or three-dimensions, require users to manipulate non-intuitive tools across a virtual workspace. For example, drawing a straight line may call for the user to move the cursor away from the drafting area to a side menu or menu bar, select a tool for creating straight lines, then returning to the workspace to specify start and stop points for the line. These actions can be replicated, Apple says, by implementing a multitouch display like those found in the company's iPad tablet lineup.
In one embodiment, the patent calls for a first touch input, which can include two separate touch events from at least two different locations on a screen. As seen above, the app can determine the number and position of touch events, or finger placement, to present a virtual tool like a ruler.
The invoked tool can persist on screen for a limited time, or until it dismissed by the user. When the tool is active, the user can resize, scale, or make other adjustments with full gesture support.
Illustration of protractor tool and multitouch input.
A second touch input involves the interaction with the virtual tool. For example, a ruler can be invoked with the first touch input, while the second input creates a corresponding line or other graphic. In some cases, the lines or shapes can have a "snap to" function to automatically size or scale the object.
The patent points out that the virtual tools can resemble traditional drafting equipment, such as a ruler, t-square, protractor, compass, and various stencils. Other embodiments allow for custom tools to be configured, with specific parameters being editable by the user.
Multiple tools are also supported, meaning users can invoke a ruler, protractor and t-square, interacting with each simultaneously. The patent goes through a number of examples, outlining possible use scenarios. For example, a virtual compass can be rotated using gestures to control output.
Illustration of virtual compass tool with gesture support.
Finally, the property allows for tool customization, including metric tic marks, while line thickness and other graphical assets are also editable.
Apple's virtual tool patent was first filed for in 2010 and credits Nicholas V. King as its inventor.