User Guide
03.2 · Annotating Images

Drawing Tools

The three free-form drawing tools are Pen, Marker, and Highlighter. All three track your cursor while the mouse button is held and commit a single stroke when you release.

Comparison

ToolDefault ColourDefault ThicknessDefault OpacityUse Case
PenRed (#FF0000)3 px100%Precise outlines, handwriting, circling items
MarkerRed (#FF0000)~6 px~70%Bolder strokes over text or screenshots
HighlighterYellow (#FFFF00)~12 px40%Highlighting lines of text without obscuring

Defaults and Settings

The tool defaults come from the Annotation section of settings:

  • Annotation.DefaultPenColor — pen and marker colour (default #FF0000).
  • Annotation.DefaultHighlightColor — highlighter colour (default #FFFF00).
  • Annotation.DefaultThickness — starting stroke width (default 3).
  • Annotation.DefaultOpacity — alpha for pen and marker (default 1.0).
  • Annotation.HighlightOpacity — alpha for highlighter (default 0.4).

Any change you make via the toolbar colour picker, thickness slider, or opacity slider overrides the default for the current stroke only. Persistent defaults live in the Settings window (see 10.5).

Drawing a Stroke

  1. Pick the tool (Pen, Marker, or Highlighter) from the annotation toolbar.
  2. Choose a colour from the swatch or recent-colours palette.
  3. Adjust thickness and opacity if needed.
  4. Press and hold the left mouse button on the canvas, drag to draw, and release to commit.

Each stroke is a single undo step.

Tip

Tip — Highlighter strokes stack. Dragging over the same region twice doubles the opacity. Use Undo if you overshoot.

Tip

Setting — To make all pen strokes start at a different colour, change Annotation.DefaultPenColor in Settings instead of re-picking the colour every capture.