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Drawing Tools

Montaris-X provides 7 drawing tools optimized for ROI delineation on scientific images. Select tools from the toolbar or use keyboard shortcuts.

Brush (B)​

Freehand drawing tool for tracing ROI boundaries.

  • Size: Adjust with [ / ] keys or the slider in the Tool Panel (1–2000 px)
  • Fine control: The size slider uses a nonlinear (quadratic) mapping for precise control at small sizes and fast sweeps at large sizes
  • Adaptive keyboard steps: [/] keys use smaller steps for small brushes (1 px below 20) and larger steps for big brushes (10 px above 500), with smooth snapping at tier boundaries
  • Auto-overlap mode: When enabled, the brush can paint over existing ROIs on other layers. Toggle in the Tool Panel.
  • Color preview: The brush cursor shows the active ROI's color

Tips:

  • Zoom in (Ctrl+=) for precise edges
  • Hold Space to pan without switching tools
  • The brush only draws on the currently selected ROI layer

Eraser (E)​

Removes pixels from the active ROI layer.

  • Size: Same [ / ] controls as the brush
  • Works identically to the brush but removes instead of adding

Polygon (P)​

Click to place vertices, creating straight-edged boundaries.

  • Click to add each vertex
  • Press Enter to close the polygon and fill it
  • Press Escape to cancel
  • Works well for regions with clean geometric boundaries

Rectangle (R)​

Click and drag to draw a filled rectangle.

  • Hold Shift to constrain to a square
  • Release to commit the shape

Circle (C)​

Click and drag to draw a filled ellipse.

  • Hold Shift to constrain to a perfect circle
  • The shape is defined by the bounding box of your drag

Stamp (S)​

Places a pre-sized rectangular or circular region.

  • Width / Height: Set in the Tool Panel
  • Click to stamp at the cursor position
  • Useful for placing uniform-sized ROIs (e.g., counting frames, sampling regions)

Bucket Fill (G)​

Flood-fills an enclosed area on the active ROI layer.

  • Tolerance: Adjust in the Tool Panel (0–255). Higher tolerance fills through more variation.
  • Click inside an enclosed boundary to fill
  • Works best after outlining a region with the brush or polygon tool

Common Controls​

ActionControl
Switch toolKeyboard shortcut
Adjust brush size[ decrease / ] increase
Pan while drawingHold Space
ZoomScroll wheel
Undo last strokeCtrl+Z
RedoCtrl+Y or Ctrl+Shift+Z