circuit-to-canvas

Draw Circuit JSON into a Canvas- works with any canvas object (Node/Vanilla)

const drawer = new CircuitToCanvasDrawer(canvasOrCanvasRenderingContext2d)

// Sets the internal transformation matrix for all operations
drawer.setCameraBounds({ minX: 0, maxX: 100, minY: 0, maxY: 100 })

drawer.configure({
  colorOverrides: {
    topCopper: "#ff0000"
  }
})

// Accepts a circuit json array, by default draws on all layers
drawer.drawElements([pcbPlatedHole], {
  layers: ["top_copper"]
})

Implementation Notes

There are two "types" of layers:

• Specific drawing layers e.g. "top_copper"
• Layer groups "top" (includes "top_copper", "top_soldermask")

inner layers go by the name inner1, inner2 etc.

Feature Parity with circuit-to-svg

This checklist tracks PCB drawing features from circuit-to-svg that are implemented in circuit-to-canvas.

PCB Elements

• pcb_board - Board outline with center/width/height or custom outline
• pcb_trace - PCB traces with route points
• pcb_via - Via holes
• pcb_plated_hole - Plated through-holes (circular, pill, oval shapes)
• pcb_hole - Non-plated holes (circular, square, oval shapes)
• pcb_smtpad - SMT pads (rect, circle, rotated_rect, pill shapes)
• pcb_copper_pour - Copper pour areas (rect, polygon shapes)
• pcb_cutout - Board cutouts (rect, circle, polygon shapes)

Silkscreen Elements

• pcb_silkscreen_text - Text on silkscreen layer
• pcb_silkscreen_rect - Rectangles on silkscreen
• pcb_silkscreen_circle - Circles on silkscreen
• pcb_silkscreen_line - Lines on silkscreen
• pcb_silkscreen_path - Paths/routes on silkscreen

Copper Text

• pcb_copper_text - Text rendered on copper layers (supports knockout mode, mirroring)

Error Visualization

• pcb_trace_error - Trace routing error indicators
• pcb_footprint_overlap_error - Footprint overlap error indicators

Debug/Development Features

• pcb_component - Component bounding box visualization
• pcb_group - PCB group visualization with dashed outlines
• pcb_courtyard_rect - Component courtyard rectangles

Fabrication Notes

• pcb_fabrication_note_text - Fabrication note text
• pcb_fabrication_note_rect - Fabrication note rectangles
• pcb_fabrication_note_path - Fabrication note paths
• pcb_fabrication_note_dimension - Fabrication dimension annotations

Annotation/Notes

• pcb_note_text - General note text
• pcb_note_rect - Note rectangles
• pcb_note_path - Note paths
• pcb_note_line - Note lines
• pcb_note_dimension - Dimension annotations

Panel Support

• pcb_panel - PCB panel outlines for panelization

Visualization Features

• Rats nest visualization - Unrouted connection indicators
• PCB grid overlay - Configurable grid with major/minor lines
• Soldermask rendering - Soldermask layer visualization
• Anchor offset indicators - Debug indicators for relative positioning