Chapter 6. Geometric Shapes

Table of Contents

Inkscape provides a number of tools for drawing geometric shapes. The tools for drawing regular[10] geometric shapes (rectangles, boxes, ellipses, regular polygons, stars, and spirals) are covered here. Path (pencil and pen) tools, discussed in the next section, may be used to draw arbitrary shapes.

Current Style:  The style of an object includes attributes that determine how the inside of the shape (fill) and how the boundary path (stroke) are drawn. It also includes shape-specific attributes such as the number of points in a star. New objects are drawn with the Current style. Some components of the Current style are displayed (e.g. Fill color) or changed (e.g. number of points in a star) in the Tool Controls of a relevant tool.

The Rectangle Tool Controls.
The Rectangle Tool-Tool Controls showing the current Fill color (blue) and Stroke color (black), as well as the Stroke width (1 px).

A component of the Current style is changed when that component is modified through, for example, an entry in the Tool Controls or the Fill and Stroke dialog (Object icon Fill and Stroke... (Shift+Ctrl+F)) discussed in Chapter 10, Attributes. Note that if in the Current style, a star has five points, just selecting a star with six points (and even modifying its color) is not enough to change the number of points in the Current style. The number of points must be explicitly changed.

By default, the shape tools (except the Spiral Tool and Box Tool) as well as the Calligraphy Tool are drawn with a global Current style. Changing the style for one of these tools, changes the style for all. Control over which tools use the global Current style and setting a default Current style can be done on each tool's entry in the Inkscape Preferences dialog (File icon Inkscape Preferences... (Shift+Ctrl+P)).

Each of the shape tools can be given a fixed style by selecting the This tool's own style option under the tool's entry in the Inkscape Preferences dialog (File icon Inkscape Preferences... (Shift+Ctrl+P)). Clicking on the Current style color swatches will open the correct section of the Inkscape Preferences dialog. Set the style by selecting an object with the desired style and click on the Take from selection button. The Box Tool style cannot be changed. (However the Box Tool with the Last used style option will remember its own style.)

While drawing some objects (arcs, stars, regular polygons, and spirals), some features (such as the orientation of a polygon) can be constrained to specific angles with respect to the center of the shape and the horizontal axis. These angles are multiples of the Rotation snap angle. The default snap angle is 15°. It can be set under the Steps entry in the Inkscape Preferences dialog.

Shapes can be scaled, rotated, and skewed. (See Chapter 5, Positioning and Transforming.) When doing so, a transformation is applied to the shape. The internal parameters defining the shape (such as the width and height of an ellipse) remain unchanged.[11] This is important to remember if you later modify a shape, for example, by editing the XML file directly.



[10] The Star Tool includes a randomization feature so that the resulting shapes are not regular. The underlying description is still based on a regular shape.

[11] This is not always true for rectangles. If the option Optimized is selected in the Store transformation section of the Transforms entry of the Inkscape Preferences dialog, the x, y, width, and height attributes will change rather than adding a transformation matrix for simple translating and scaling operations.