What is Doodleback?

A lot of drawing apps let you construct a circle but usually in only one way. They let you copy an object but in only one way or erase but in only one way. But what if you wanted to erase with a star or copy something by rotation? Doodleback’s philosophy is that how you’re able to construct things is almost as important as what you can construct. Being able to precisely place objects at the moment of their creation simplifies many drawings that would otherwise be difficult or almost impossible. You can get it here on Google Play.

Tangent Segment

The Tangent Segment tool lets you create a segment that is tangent to a circle, either real or imaginary. We say “real or imaginary” because really what you’re doing is selecting a center and a radius and then drawing a tangent line to that imaginary circle. If there happens to be a real circle there too, then you’ll draw a tangent line to it. Your initial touch define the start of the tangent line. [Read More]
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Null Measurement

The Null Measurement functions exactly as the Measurement tool except that the Measurements created are immediately removed as soon as you lift your finger. You might want to do this if you want to measure things on your model without actually altering the model. Like the Measurement tool, you’ll need to define a Reference Length first. Here’s an example:

Reference Length

The Reference Length tool allows you to specify a unit length that can be used by the Measurement tool for measurement. The segment is constructed in the same way that a Line Segment is constructed. When the construction is completed, a dialog box will be presented asking you to specify the length of the segment. The default is 1 but you can enter any positive value that you want. You can have more than one Reference Length. [Read More]

Measurement

The Measurement tool is used to measure distances on the screen using a Reference Length as its basis. The construction is the same as for a Line Segment. If no Reference Length has been constructed yet the Measurement has no way of measuring the distance so the construction will be cancelled. Note that the measurement is accurate at the scale of its construction. If the Measurement path is rescaled, the value will be no longer be valid. [Read More]

Measurement Sum

The Measurement Sum tool is used to find the sum of all the Measurements in a selected region. The region can be selected using either a rectangular area or a circular area. The sum will only include Measurements that correspond to the currently selected Reference Length, and the sum itself will simply be a Text Path centered in the selected region. You can move the text anywhere you like after construction using one of the Transformation tools such as the Move tool. [Read More]

Switch Reference Length

The Switch Reference Length tool is used to change the Reference Length that is used by the Measurement tool. You can have more than one Reference Length. The currently selected one will have an asterisk(*) besides its number, and that length will be used for measurements made with the Measurement tool and Null Measurement tool. Simply tap another Reference Length segment using this tool to select it. Here’s an example: [Read More]

Connected Collection of Points

The Connected Collection of Points tool creates a Bound collection of Line Segments from a selected group of Points. It connects every Point to every other Point and will produced a shape like this: You have the option of binding the line segments using normal binding or Layer Binding. You also select how many Bezier Points each line segment will use and whether or not to delete the original Points. [Read More]
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Convex Hull

The Convex Hull tool creates a polygon essentially by wrapping a rubber band around a collection of paths. You have two construction options Consider ALL Paths Points Only The Points Only option will only use Points for the wrapping and ignore all other paths. The Consider ALL Paths option will use all the Snapping Points on every path within the selection rectangle. This can be very useful for creating hybrid curved/straight shapes. [Read More]
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Mark Point Polygon

The Mark Point Polygon tool is similar to the Point Trace Polygon tool except that instead of laying out Points in advance you “mark” the vertices with the Mark Button Simply move your finger to a position and press the mark button to select the next vertex. You can use the Drag Constraint button to align the next vertex horizontally or vertically with the last vertex. [Read More]
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Point

The Point tool creates a point on the page. It is created where your finger first touches the canvas. If you have Snapping enabled, the point may be drawn at a snapping point of another path if your initial touch is near enough to one. Points are useful as guides in the construction of other paths. For example, they can be used with the Point Trace Polygon tool to easily draw an irregularly shaped polygon. [Read More]
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