A Guide to Inkscape/Path Drawing Tools

P

aths can be created by Path Tools, Pencil, Bezier, and Calligraphy, rendering and object conversions. Rendering of pre-configuured objects can be created using the ‣Extensions <Render> Menu bar features. Converting an existing shape or text object to a path, can also create paths:

• ‣Path ‣‣Object to path
• ‣Path ‣‣Stroke to path

Unlike the use of shape handles for editing, path objects use three types of path nodes. The start/end and corner(s) of a path are referred to as Cusp Nodes ◇ nodes along a path. A path's curve settings are provided by two types of Smooth Nodes, □ smooth and auto-smooth ○ Nodes . Smooth nodes can have one straight segment and one curved segment on either side of the node. The Cusp and Smooth Nodes have handles that are used to set the node's length (x,y value of the handle itself) its angle and distance, the 'tool-tip message' in the Status Bar displays this dynamic information. Spiro based paths do not respond to node handle positioning edits and if the handles are retracted for auto-smooth nodes, the node will change to either a smooth or cusp node.

There are thin red lines between path nodes and are used to edit a 'segment' between two nodes. To view the red line segment editing, you must change from the Path Tool (P, B and C) to the Node Tool (N). When you mouse-over 🖰 a segment the Node Tool cursor changes to a pointer with a fist. This segment editor can also change a segment from a curve to a straight line or vice versa. Once a segment is selected (clicked) the two adjacent path nodes change color and the edit is applied by either dragging the segment or using the Tools Controls bar edits. The Tool Controls bar can be used for many edits; change selected segment(s) to a line; change selected segment(s) curves; delete the segment between two non-end points. This segment based editing also impacts the editing of Spiro paths.

The default stroke, fill and Ctrl+Click settings of the tools can be set using:

• ‣Edit ‣‣Preferences <Pencil>, <Bezier> and <Calligraphy> settings.

	Pencil tool
	Bezier curve and Straight line tool
	Calligraphy tool

Pencil Tool - Bezier (Freehand)

Pencil Tool:
1.) Set to Bezier (Freehand) Mode

Keyboard shortcut: P or F6

The Pencil Tool creates two styles of a path and dots (circle shapes). The first (default) option creates freehand Bezier curves and lines. Freehand drawing can be done in two ways. (1) By dragging (press+hold) the mouse 🖰 on the canvas. (2) By a series of Clicks and Releases, example Click on the canvas (don't drag) then move the cursor to another location and Click again this will create a path segment. Additional segments can be added to the first segment, by clicking on one of the end nodes. This Click-Release method is helpful when creating Spiro paths.

Once a path is created, there are three options for editing the path nodes. (1) To reduce the number of nodes on a given path use the path simplify command; ‣Path ‣‣Simplify (Ctrl+L). (2) To add nodes to an existing path place the mouse cursor 🖰 over a start/end node, the node will change color left click and either drag or click to another position on the canvas. (3) Once a path is created the Node Tool can edit the nodes, it has an extensive set of node and segment editing features, available in the Tool Controls bar.

Pencil Tool - Spiros

Pencil Tool:
2.) Set to Spiro Mode

Keyboard shortcut: P or F6

The second mode of editing, enabled by using the Tool Controls bar, creates a Spiro based path which involves both cusp ◇ and smooth ○ nodes . Smooth nodes apply spiro based interconnection to adjacent nodes within the path. Once the spiro path is created, the Node Tool must be used to edit the positioning of the spiro's smooth and cusp nodes. Even though smooth node handles are displayed on Spiro paths they do not impact editing of the Spiro. The positioning (vector) of smooth nodes in relation to adjacent cusp/smooth nodes is how a spiro's rendering is calculated. The thin red line segment editor can be used to set a straight or curved segment within a spiro.

Note - The pencil tool's spiro rendering is based on the Smooth setting of the Tool Controls bar. Smoothing is how much path simplifying nodes are applied to the spiro being created. If smoothing is set too low, there will be no effect (vector distance between nodes dependent), set to high and the smoothness will render a straight line.

Pencil Tool - Dots (Circle Shapes)

3.) Creating Dots, using command keys

The pencil tool can also create single dots (circle shapes), using command keys;

• Ctrl+L-Click creates a dot shape ○
• Ctrl+⇧ Shift+L-Click creates a dot twice the size of the
  Ctrl+L-Click dot ○
• Ctrl+⇧ Shift+Alt+L-Click creates a random radius dot ○
  

Once the dot is created, the editing is now changed over to the Ellipse Tool. The dot radius can be set in the Preferences of the pencil tool, ‣Edit ‣‣Preferences <Tools> <<Pencil>> (Ctrl+⇧ Shift+P) "Ctrl+Click radius setting: xox times current stroke width".

This dot creation can be used as a work-around for creating text bullets, as of Inkscape v0.91 there is no internal support, other than Unicode values, for bullets in any native Text formatting.

Bezier Curve tool

Keyboard shortcuts: B or ⇧ Shift+F6

Above is an example of a bezier curve. You can see two nodes in this view. These are the start and end nodes of the curve. But there are path nodes with control handles that you cannot see. These determine how the line curves between the end nodes. In order to view and edit path (stroke) nodes you will need to click on the Node tool button (N}.

Node tool

Keyboard shortcuts: N or F2

Clicking on the node tool reveals another node in the middle of the curve.

If you then click on the middle node you will see the bezier handles appear.

These handles allow you to change the shape of the curves between the nodes. Notice that a list of node tools appear at the top. You can use these to change the nodes. We will not go into detail about these tools in this beginners tutorial.

The node tool can be used on all the objects created with the other tools to reveal their nodes.

More on the drawing tools

The other two drawing tools also create paths. The top tool of the three is the scribble tool . Use it like a pencil. The computer will calculate all the nodes and beziers for you. Closed paths can be created by drawing a loop. (With the bezier tool, click on the start node to close the curve).

The last tool in the group is the calligraphy tool. It allows you to do calligraphic writing. The pen creates closed loops in a realistic pen nib like way. Because of this many graphic artists like to draw with this pen all the time.