fix: implement two-layer soldermask approach for copper pours

[RaghavArora14]

Summary

Implements a two-layer soldermask approach for copper pours, following the design discussed with Rishabh. This approach avoids boolean operations and uses SVG layering instead.

Changes

Core Implementation

• Two-layer soldermask approach: Base board soldermask layer + individual cutout/overlay elements per copper pour
• No boolean operations: Uses SVG layering and type priorities for correct rendering order
• Substrate-only support: Copper pours with substrate_only in ID render only substrate cutout (no copper element)

Technical Details

Rendering Order

1. Base board soldermask (soldermask-top/soldermask-bottom, priority 3)
2. Soldermask cutouts (pcb_soldermask_opening, type priority 25, on actual copper layer)
3. Copper elements (traces, pads, pours, type priority 30-35)
4. Soldermask overlays (pcb_soldermask, type priority 40, on actual copper layer)

Substrate-Only Detection

Copper pours with substrate_only in their ID skip rendering the copper element, showing only the substrate cutout. This allows testing pure substrate areas without copper blending.

Testing

All existing tests pass. New comprehensive test covers:

• Covered copper pours (with soldermask overlay)
• Uncovered copper pours (with substrate cutout + copper)
• Substrate-only areas (pure substrate, no copper)
• Both top and bottom layers
• Various shapes (rect, polygon, rotated rect)

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Project	Deployment	Preview	Comments	Updated (UTC)
circuit-to-svg	Ready	Preview	Comment	Nov 25, 2025 6:25pm

[ShiboSoftwareDev]

there is an inconsistency with what maskLayer is across files

[RaghavArora14]

there is an inconsistency with what maskLayer is across files

Standardized maskLayer usage across files and added comments explaining the pattern:

1. Base board mask (create-svg-objects-from-pcb-board.ts): Uses soldermask-top/soldermask-bottom (the soldermask layer name)

2. Cutouts/overlays (all other files): Use the actual element layer (top/bottom):

   • Holes: Use view layer (ctx.layer ?? "top") since they're through-hole
   • Plated holes: Use the extracted copperLayer from the element
   • Copper pours: Use the layer parameter
   • SMT pads: Use pad.layer directly

The distinction is:

• Base board mask → soldermask-top/soldermask-bottom
• Individual cutouts/overlays → top/bottom (actual copper layer)

[ShiboSoftwareDev]

one time it's this:
const maskLayer = layer ?? "top"
and another time it's this:
const maskLayer = ctx.layer === "bottom" ? "soldermask-bottom" : "soldermask-top"
it should be consistent for clarity

[RaghavArora14]

one time it's this:
const maskLayer = layer ?? "top"
and another time it's this:
const maskLayer = ctx.layer === "bottom" ? "soldermask-bottom" : "soldermask-top"
it should be consistent for clarity

Fix: Standardized maskLayer determination across files: extract the layer to a layer variable first, then derive maskLayer from it. Replaced all copperLayer references with layer in the plated hole file to match the pattern and fix TypeScript errors.

[RaghavArora14]

1. Fixed variable naming typo: shouldshowSolderMask → shouldShowSolderMask in SMT pads and panel files
2. Standardized maskLayer derivation pattern:
   • All files now extract layer first, then derive maskLayer from it
   • Board file: maskLayer = layer === "bottom" ? "soldermask-bottom" : "soldermask-top"
   • Other files: maskLayer = layer
3. Fixed SMT pads file:
   • Added const layer = pad.layer and const maskLayer = layer
   • Replaced all pad.layer references with layer or maskLayer as appropriate
4. Standardized data-pcb-layer usage:
   • Copper elements always use layer
   • Soldermask elements always use maskLayer
5. Fixed plated hole file:
   • Replaced all copperLayer references with layer
   • Added missing data-pcb-layer: maskLayer to 4 soldermask elements that were missing it
6. Removed direct property access:
   • No more pad.layer or ctx.layer in data-pcb-layer attributes
   • All use extracted layer or maskLayer variables
7. Added clarifying comments explaining when to use layer vs maskLayer in each file

[ShiboSoftwareDev]

update snapshots

[seveibar]

Do not obfuscate, there is a ton of it. Eg layer = pad.layer

[seveibar]

this is getting better

[RaghavArora14]

done all changes

[tscircuitbot]

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PR Rating: ⭐⭐⭐
Impact: Major

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