Apple patent filing involves a virtual drawing aid for CAD features on an iPad — Apple World Today

The patent filing is for a sketch area on a touch-sensitive display that receives one or more drawing inputs. In the patent filing, Apple motes that computer-programs that provide virtual design and drawing tools have wide applicability in both industrial and personal use settings. Some applications provide free-hand sketching capabilities that allow a user to draw lines and objects based on free-hand movement of a contact (e.g., a contact made by a finger or stylus) on a touch-sensitive surface (e.g., a trackpad or touch-screen display). 

In addition to selecting the color and texture for a drawing tool (e.g., pen, brush, pencil, etc.) used, a user may wish to employ certain conventional drawing aids, such as a straight-edge ruler, a template, a protractor, an angle ruler, etc. It is inconvenient and difficult to use a real-world drawing aid with a virtual drafting environment. 

Apple says that providing virtual drawing aids in computer programs that provide sketching capabilities will improve the functionality of the computer programs. However, the tech giant says it’s challenging to provide virtual drawing aids in a way that’s “functional, efficient, and ease to use.” Apple obviously thinks it can do this.

Here’s the summary of the invention: “In response to receiving the one or more drawing inputs, the device displays marks based on the drawing inputs that are constrained based on the drawing aid. While displaying the drawing aid in the sketch area, the device detects a touch gesture at a location corresponding to a location of the drawing aid. In response to detecting the touch gesture: if the touch gesture is a pinch gesture, the device ceases to display the drawing aid in the sketch area; and if the touch gesture is a rotational gesture, the device rotates the drawing aid relative to the sketch area in accordance with the movement of at least one contact in the touch gesture while maintaining display of the drawing aid in the sketch area.”