Canvas & Document
Paint Forge provides a flexible canvas system with configurable dimensions, grids, guides, and multiple view modes. This page covers everything related to the document canvas, viewport navigation, and visual overlays.
Canvas Settings
Canvas settings control the dimensions, background, and metadata of your document. Access them from the Canvas Settings panel in the right sidebar.
Dimensions
Set the canvas width and height in pixels. The resize dialog offers 13 presets organized into four categories:
- Screen: common display resolutions (1920x1080, 2560x1440, etc.)
- Social Media: platform-optimized sizes (Instagram, Twitter, Facebook, etc.)
- Print: standard print formats (A4, Letter, etc.)
- Mobile: phone and tablet screen sizes
Custom Presets
Save frequently used canvas dimensions as custom presets. Up to 8 custom presets can be saved and recalled from the Canvas Resize dialog. A performance warning appears when the total pixel count exceeds 4 million pixels.
Resize with Anchor
When resizing the canvas, a 3x3 anchor grid lets you choose where existing content is positioned within the new dimensions. For example, selecting the top-left anchor places content at the top-left corner, adding new space to the right and bottom.
Background
Choose a solid background color using the color picker, or enable transparent background mode. When transparent background is active, the canvas renders a checkerboard pattern to indicate transparency. PNG export preserves the alpha channel, while JPEG and WebP formats fall back to the configured background color.
DPI Metadata
Set the document DPI (dots per inch) for print workflow reference. This is a cosmetic value that does not change pixel dimensions. Preset buttons are available for common values: 72, 150, 300, and 600. Physical dimensions in inches and centimeters are displayed in the Canvas Settings panel, the Status Bar, and the Export dialog.
DPI is metadata only and does not resample the image. To change actual pixel dimensions, use the Canvas Resize dialog.
Grid
The grid overlay helps with precise object placement and alignment. Two grid types are available, toggled from the Canvas Settings panel or the View menu.
| Grid Type | Description |
|---|---|
| Rectangular | Standard square grid overlay. Grid intersections serve as snap targets. |
| Honeycomb | Pointy-top hexagons with odd-row offset. Snap targets are hex centers. |
- Grid size is configurable with a slider, plus preset buttons for 8, 16, 32, and 64 pixels
- Grid color is customizable
- Snap to Grid constrains object positions to grid intersections (rectangular) or hex centers (honeycomb)
- Toggle grid visibility from the View menu or Canvas Settings panel
Pixel Grid
A separate 1px pixel grid appears automatically at 800% zoom and above, showing individual pixel boundaries. This is independent of the configurable grid overlay and can be toggled separately in the View menu or Canvas Settings panel.
The pixel grid only appears at very high zoom levels (800%+) where individual pixels are large enough to distinguish. It is useful for pixel art and precise retouching.
Rulers & Guides
Horizontal and vertical rulers appear along the top and left edges of the canvas. Guides are draggable reference lines that can be used for alignment and layout.
- Create guides by clicking and dragging from the horizontal or vertical ruler onto the canvas
- Each guide has an independent visibility toggle
- Enable Snap to Guides to have objects snap to nearby guide lines
- Right-click a ruler to open a context menu with: Add Guide Here, Clear All Guides, Toggle Snap to Guides
- Guides rotate with the canvas when canvas rotation is active
Guide Presets
Five built-in guide presets are available for common layout patterns. Presets use percentage-based positioning so they adapt to any canvas size. Custom presets can be saved and loaded.
| Preset | Description |
|---|---|
| Thirds | Divides the canvas into a 3x3 grid |
| Center Cross | Horizontal and vertical center lines |
| Golden Ratio | Lines at golden ratio proportions |
| Margins 10% | Inset guides at 10% from each edge |
| Halves & Quarters | Half and quarter divisions |
Smart Guides
Smart guides are dynamic alignment helpers that appear when dragging objects. They show snap points to other objects’ edges and centers, making it easy to align elements precisely without manual guide placement.
- Alignment guides appear during object drag showing snap to edges and centers of other objects
- Distance labels display the gap measurement between snapped objects as a "Npx" pill label with a perpendicular measurement line
- Group layer bounding boxes are included as snap targets
- Configurable snap threshold from 1 to 20 pixels (default 5px) in Canvas Settings
- Toggle smart guides on or off in the Canvas Settings panel
Snap to Pixels
Enable Snap to Pixels in the Canvas Settings panel to automatically round object positions and dimensions to whole pixel values during move, resize, and creation operations. This ensures crisp edges on raster-targeted artwork.
Smart guides work alongside Snap to Grid and Snap to Guides. When multiple snap systems are active, the closest snap target wins.
Symmetry Painting
Symmetry painting mirrors brush strokes across one or more axes in real time. Guide lines on the overlay canvas indicate the active symmetry axes. Configure the symmetry mode in the Canvas Settings panel.
| Mode | Description |
|---|---|
| Vertical | Mirrors strokes left/right across the vertical center of the document |
| Horizontal | Mirrors strokes top/bottom across the horizontal center |
| Both | Mirrors on both axes simultaneously (4-fold symmetry) |
| Radial / Mandala | Rotational symmetry with 3 to 32 fold count, distributed evenly around the center |
Supported tools: Brush, Eraser, Raster Brush, Spray Paint, Calligraphy, Blur, Sharpen, Dodge/Burn, and Smudge.
The Status Bar shows the active symmetry mode with a green indicator. Click the indicator to disable symmetry painting.
Composition Guides
Composition guides are overlay lines that help frame your artwork according to classical composition principles. Toggle them from the View menu, Canvas Settings panel, or Command Palette. Only one composition guide type is active at a time.
| Guide | Description |
|---|---|
| Rule of Thirds | 3x3 grid overlay dividing the canvas into nine equal regions |
| Golden Ratio | Lines positioned at golden proportion divisions |
| Diagonals | Corner-to-corner diagonal lines |
| Center Cross | Crosshair at the exact center of the canvas |
| Isometric | 30-degree and 60-degree angle grid for isometric illustration |
| Action Safe | 90% centered rectangle indicating the broadcast-safe area |
| Title Safe | 80% centered rectangle indicating the title-safe area |
- Guide color is configurable (default amber)
- Guide opacity is adjustable from 0 to 1 (default 0.5)
- Toggle via View > Composition Guide submenu
- Composition guides are view-only overlays and do not appear in exported images
Canvas Operations
These operations modify the canvas dimensions or content structure. They are available from the Image menu and Command Palette.
| Operation | Description |
|---|---|
| Resize Canvas | Adjust canvas dimensions with an anchor grid to position existing content within the new size |
| Auto-Crop to Content | Scans all visible layers for non-transparent pixels and crops the canvas to the tightest bounding box around content |
| Expand Canvas to Content | Grows the canvas when vector objects extend beyond the current document boundaries |
| Flip Canvas Horizontal | Mirrors all layers’ raster data, mask data, and vector object positions left-to-right |
| Flip Canvas Vertical | Mirrors all layers’ raster data, mask data, and vector object positions top-to-bottom |
| Flatten Image | Composites the full document (raster, vector, adjustments, masks, blend modes, background) into a single flat raster layer and removes all other layers |
Flatten Image is a destructive operation. When the auto-snapshot preference is enabled, a named snapshot is created automatically before flattening so you can restore the original layer structure if needed.
View Modes
View modes change how the canvas is displayed without affecting the actual image data. They are all view-only and do not affect export output.
Outline Mode
Outline mode renders all objects as blue 1px outlines on a white background, hiding fills, raster content, and effects. This is useful for inspecting object placement and overlap without visual clutter. Toggle with Ctrl+Shift+O or from the View menu.
Color Blindness Simulation
Simulate how your artwork appears to viewers with different types of color vision deficiency. This is a post-composition filter applied to the display only.
| Mode | Description |
|---|---|
| Protanopia | Reduced sensitivity to red light |
| Deuteranopia | Reduced sensitivity to green light |
| Tritanopia | Reduced sensitivity to blue light |
| Achromatopsia | Complete color blindness (monochrome vision) |
Exposure Clipping Overlay
The exposure clipping overlay highlights pixels that may be losing detail due to extreme brightness or darkness. Blown highlights are shown with a red overlay, and crushed shadows with a blue overlay. Thresholds are configurable: the highlight threshold defaults to 250 (range 200-255) and the shadow threshold defaults to 5 (range 0-50). Toggle from the View menu or Canvas Settings panel.
Render Stats
The render stats overlay displays a small pill in the corner of the canvas showing the current frames per second (rolling 60-frame average), layer count, object count, and document dimensions. Toggle from the View menu or Canvas Settings panel.
Zoom & Viewport
The viewport controls how you navigate and view the canvas. Zoom, pan, and rotate the view without affecting the underlying document content.
Zoom Shortcuts
| Shortcut | Action |
|---|---|
| Ctrl | += / - — Zoom in / out |
| Ctrl | +0 — Reset to 100% |
| Ctrl | +Scroll wheel — Zoom centered on cursor |
| Zoom presets | 25%, 50%, 100%, 150%, 200%, 300% available in the zoom dropdown |
| Click zoom % | Click the zoom percentage in ZoomControls to type a custom value |
Fit & Fill
- Fit to Screen: scales the document to fit within the viewport with 16px padding on all sides, resets rotation to 0
- Fill Screen: scales to fill the viewport using the larger scale factor (may crop edges), resets rotation to 0
- Zoom to Selection: fits the selected objects within the viewport with 40px padding
- Zoom to Layer: fits a specific layer within the viewport
- Zoom to All Layers: fits the union bounds of all visible layers within the viewport
Panning
| Method | Description |
|---|---|
| Space + drag | Hold Space from any tool to temporarily pan the canvas |
| Middle-click + drag | Middle mouse button pans the canvas directly |
| Scroll wheel | Bare scroll wheel pans vertically |
| Shift + scroll wheel | Pans horizontally |
Canvas Rotation
Canvas rotation is a non-destructive view transform. The rotation does not affect export output or object positions.
| Shortcut | Action |
|---|---|
| Alt + scroll wheel | Rotate canvas 1 degree per scroll tick |
| Alt+Shift + scroll wheel | Rotate in 15-degree increments |
| Escape | Reset rotation to 0 degrees |
The current rotation angle is displayed in the Status Bar. Click the rotation display to reset it to zero.
Viewport History
Paint Forge tracks your zoom and pan changes in a navigation history stack (up to 20 entries, debounced at 600ms). Navigate back and forward through your viewport positions just like browser history.
| Shortcut | Action |
|---|---|
| Alt+ArrowLeft | Navigate back to the previous viewport position |
| Alt+ArrowRight | Navigate forward to the next viewport position |
Two-finger pinch on a trackpad or touch screen zooms the canvas, and two-finger rotate gestures rotate the canvas view.
Scale Calibration
Scale calibration lets you assign real-world measurements to pixel distances so the Measure tool can display distances in physical units (inches, feet, centimeters, millimeters, meters). This is useful for architectural plans, maps, or any document where pixel distances represent real-world lengths.
- Access Scale Calibration from the Measure tool options bar
- Draw a reference line over a known distance on the canvas, then enter the real-world length and unit
- Supported units: pixels, inches, feet, centimeters, millimeters, meters
- Once calibrated, the Measure tool displays distances in the configured unit with automatic format (e.g. "3.5 cm")
- Calibration is saved with the project (serialized in project metadata)
- The cumulative polyline mode of the Measure tool also uses the calibrated scale for per-segment and running-total labels