Tools & Interactions
A reference guide to all built-in tools, their controls, modifier keys, and viewport camera operations in OpenGPEX.
Built-in Tools
| Tool |
Sidebar Icon |
Description |
| Crop |
✂️ |
Resize the canvas or cut layer to region |
| Adjustment |
🎨 |
Non-destructive brightness, contrast, HSL |
| Brush |
🖌️ |
Freehand pixel painting |
| Eraser |
🧽 |
Non-destructive mask-based erasing |
| Text |
T |
Add and edit vector text layers |
| Transform |
↔ |
Move, scale, rotate selected layer |
Tool Activation
- Click a tool icon in the left sidebar to activate it
- Only one tool can be active at a time
- The Option Bar updates to show tool-specific controls
- The Viewport Overlay shows tool-specific handles
Crop Tool
| Control |
Action |
| Drag corner handles |
Resize crop box |
| Shift + drag |
Lock aspect ratio |
| Drag inside box |
Reposition crop region |
| Enter / Apply button |
Commit crop |
| Escape / Cancel |
Discard crop |
| Option bar presets |
Common aspect ratios (16:9, 4:3, 1:1, free) |
Brush & Eraser
| Control |
Action |
| Click + drag |
Draw stroke |
[ / ] |
Decrease / increase brush size |
| Shift + click |
Draw straight line to last point |
| Pressure sensitivity |
Varies opacity (stylus only) |
| Option bar sliders |
Size, opacity, hardness |
📌 The eraser uses a non-destructive bitmap mask internally — original pixels are never deleted.
Transform Tool
| Control |
Action |
| Click + drag layer |
Move layer |
| Drag corner handle |
Scale (proportional with Shift) |
| Drag edge handle |
Scale one axis |
| Drag rotation handle |
Rotate freely |
| Shift + rotate |
Snap to 15° increments |
| Alt + drag |
Scale from center |
| Arrow keys |
Nudge 1px (Shift = 10px) |
Text Tool
| Control |
Action |
| Click on canvas |
Create new text layer |
| Double-click text layer |
Enter edit mode |
| Drag text bounding box |
Resize text area |
| Option bar |
Font family, size, weight, color, alignment |
| Escape |
Exit text editing mode |
Camera / Viewport Controls
| Input |
Action |
| Space + drag |
Pan viewport |
| Middle mouse drag |
Pan viewport |
| Scroll wheel |
Zoom in/out (centered on cursor) |
| Pinch gesture (trackpad) |
Zoom in/out |
Ctrl + 0 |
Fit canvas to viewport |
Ctrl + 1 |
Zoom to 100% (actual pixels) |
Ctrl + + / Ctrl + - |
Zoom in / out (stepped) |
Modifier Key Summary
| Key |
Global Effect |
| Shift |
Constrain proportions / snap angles |
| Alt/Option |
Transform from center / clone on drag |
| Space |
Temporarily activate pan tool |
| Ctrl/Cmd |
System shortcuts (undo, zoom, etc.) |
Next Steps
Last updated: 2026-06-14
