Docs Reference

Mouse, pen and trackpad

Every click, drag, wheel tick and modifier, on the canvas, in the panels, and what a graphics tablet adds.

Celas Studio expects a three-button mouse with a wheel, and gets more out of a pen: pressure and tilt both feed the brush engine. Nothing here needs to be configured: the modifiers below are fixed and follow the conventions of Photoshop and Affinity.

Left button draws, selects and drags. Right button opens context menus. Middle button pans, wherever you are on the canvas.

Moving around the canvas

GestureWhat it does
WheelZoom around the cursor, one 1.1x step per tick, between 0.05x and 100x
Middle-dragPan: it keeps tracking even when the cursor leaves the canvas
Space + left-dragPan, from any tool. Holding Space alone shows the open-hand cursor
Ctrl + Space + left-dragRotate the view around the centre of the canvas
Left-drag with the Hand toolPan
Left-drag with the Rotate View toolRotate the view; the drag continues outside the canvas

A wheel tick is ignored while you are mid-drag on artwork, so a nudge of the wheel cannot zoom out from under a move. Pan and zoom are both switched off in Camera View and in the 3D view. Ctrl+0 fits the canvas again and clears any view rotation.

On macOS the trackpad behaves natively: two-finger scroll pans, pinch zooms around the cursor, and Command or Ctrl with the wheel zooms for an external mouse. On Windows and Linux the wheel always zooms and there is no scroll-to-pan. There is no preference to swap the two.

Selecting and transforming

GestureToolWhat it does
Ctrl or Shift + clickMoveAdd or remove that shape from the selection
Click on empty spaceMoveClear the selection and start a marquee
Ctrl or Shift + marqueeMoveMarquee adds to the selection instead of replacing it
Double-clickMove, TransformEnter a Symbol, or step one level down the hierarchy toward the layer under the cursor
Right-clickMoveSelect what is under the cursor if it was not selected, and open the canvas menu
Shift + drag a corner handleTransformScale uniformly; on a side handle it locks the aspect
Shift + rotateTransformSnap rotation to 15 degree steps
Alt + drag a handleTransformScale from the centre, as if the pivot were centred
Ctrl + drag the anchorTransformSnap the anchor to the nine points of the bounding box; the snap points appear while you hold it

Drawing and node editing

GestureToolWhat it does
Shift + click an anchorNodeAdd or remove that vertex from the vertex selection
Alt + drag an anchorNodePull handles out of it, making the node smooth and clearing its corner radius
Double-click an anchorNodeToggle between smooth and sharp
Right-click a vertexNodeOpen the vertex menu
Alt while dragging a handleNode, PenBreak the tangent so the two handles move independently
Alt + click a handlePen, while drawingGrab that existing handle and edit it
Right-clickPen, while drawingFinish the path: the same as pressing Esc
Shift + dragRectangle, Ellipse and the other shape toolsConstrain to a square or a circle
Double-click the gradient lineGradientAdd a colour stop where you clicked

Pixel selections and painting

GestureToolWhat it does
Shift + dragMarquee, Magic Wand, lassoAdd to the selection, whatever the mode dropdown says
Alt + dragMarquee, Magic Wand, lassoSubtract from the selection
Shift + Alt + dragMarquee, Magic Wand, lassoIntersect with the selection
Click, then double-clickPolygonal marqueeEach click adds a corner; the double-click closes and commits it
Shift while scalingFloating selectionScale uniformly
Shift while rotatingFloating selectionSnap to 15 degree steps
Alt + dragWeight Paint in paint modeErase weight instead of painting it
AltBoneReveal and grab the start and end handles of a bone
Right-clickBoneDeselect every bone

Alt with the left button is a temporary eyedropper in almost every tool: it samples the colour under the cursor and hands it to the fill. Hold Shift as well and it goes to the stroke instead. The exceptions are the Node, Pen and Bone tools, and the Weight Paint tool in paint mode, where Alt already means something else. Brush and Smudge strokes will not start while Ctrl or Alt is down, for the same reason.

The canvas with Alt held, showing the eyedropper cursor and the sampled-colour preview beside it.

Panels

GesturePanelWhat it does
WheelTimelineScroll the track list vertically
Ctrl + wheelTimelineZoom horizontally around the frame under the cursor
Shift + wheelTimelinePan horizontally
Horizontal wheel or two-finger swipeTimelinePan horizontally
Ctrl or Shift + box-dragTimelineAdd the boxed keyframes to the selection instead of replacing it
Double-click a layer rowTimelineRename the layer
Right-click the tag barTimelineAdd a tag or group marker
WheelGraph EditorPan vertically
Shift + wheelGraph EditorZoom horizontally around the cursor
Ctrl + wheelGraph EditorZoom vertically around the cursor
Middle-dragGraph EditorPan
Shift while dragging a handleGraph EditorHold the tangent flat
Ctrl while dragging a handleGraph EditorMirror the handle onto the neighbouring keyframe
Ctrl + click a rowLayersAdd or remove that layer from the selection
Shift + click a rowLayersSelect the range from the primary selection to that row
Double-click a rowLayersRename the layer inline
Double-click an itemLibrary, VariantsEnter the symbol, or apply the variant
Double-click a tab barAny docked panelCollapse the panel to its tab strip, or restore it
Ctrl and Shift with the wheel do not mean the same thing in the two panels. In the Timeline, Ctrl zooms and Shift pans. In the Graph Editor both zoom, on different axes: Shift horizontally and Ctrl vertically, and plain wheel pans instead. It is worth learning both rather than guessing.

What a pen adds

A tablet gives you two extra streams, and both are recorded per point along the stroke:

  • Pressure, from 0 to 1, drives brush size and opacity through the dynamics in Brush Studio.
  • Tilt, on both axes, is folded into a single tilt angle that shape and grain settings can read.

A mouse reports full pressure on every point, so mouse strokes come out at the brush's maximum size with no thick-and-thin. That is by design: it keeps a mouse usable rather than making it draw hairlines.

Input is read straight from the tablet driver: Wintab on Windows, with the Windows Pointer API as the fallback when Windows Ink is switched on in the driver; NSEvent on macOS; XInput2 on Linux, including Wayland through XWayland.

Three pen features are not supported in Early Access: the eraser end of the stylus does not switch to the Eraser tool, the barrel buttons on the pen do nothing, and barrel rotation is not read. Assign what you need to the tablet's own express keys instead.