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Reassign Source Surface

Drafts shared side feature lines on each property side line and a flat pad feature line over the building setback for every selected lot, then adds the whole batch to the proposed lot grading surface as breaklines in one operation.

Command VDCGRADELOTS VDCGRADELOTS_REFRESH VDCGRADELOTS_RESURFACE · VDC Civil tab › Grading panel

VDCGRADELOTS_RESURFACE is part of Auto-Grade Lots; the full section follows.

Drafts shared side feature lines on each property side line and a flat pad feature line over the building setback for every selected lot, then adds the whole batch to the proposed lot grading surface as breaklines in one operation.
Per lot: 2 shared side FLs (sloped) + 1 flat pad FL over the setback. Sides sampled separately at each front corner. Proposed road FG surface (sampled at each side's front corner) LOT 6 LOT 7 LOT 8 LOT 9 C-PROP-STBK FL-LOT-6-7-SIDE FL-LOT-7-8-SIDE FL-LOT-8-9-SIDE PAD FL (FLAT) EL = 32.55 Slope 1.00% (Mode A: front to back) Front PI = road FG @ corner = ceil((max side high PI + 0.50) × 20) ÷ 20
Parcel boundary   Side FL C-TOPO-FEAT-SWALE-LOT   Pad FL C-TOPO-FEAT-PADS   Setback input C-PROP-STBK   Road FG (sampled)

What it does, per lot

  • Topology: user clicks the front edge; tool finds back (most parallel + farthest) and the two sides.
  • Front sample: proposed road FG sampled at each side's front corner separately, so each side reflects road cross-slope or super.
  • Side FLs: drafted on shared property lines, named lower-lot-first (FL-LOT-6-7-SIDE). Adjacent lots picked in the same run share one FL automatically.
  • Pad FL: traced from your existing setback polyline (default layer C-PROP-STBK), or generated from the lot when the drawn setbacks don't match the pads: a rectangle (pad size + front setback) or the lot lines inset by front/rear/side setbacks. Stamped flat at ceil((max side high PI + 0.50) × 20) ÷ 20 ft.
  • Breaklines: all FLs added to the proposed lot grading surface in one batched op, then surface rebuilds. The op is named for the lots graded, e.g. VDC Lot Grading (Lots 1-45, 135 FL), so Surface Properties shows which lots it covers, not just a count.

Modes & layers

  • Mode A (default): single 1.00% slope from front to back, 2-PI side line, all water to the road.
  • Mode B: 3-PI side, front, mid-point ridge (high), back. 1.50% default both ways.
  • Mode C: front high point at road FG, falling to the rear, all water to the rear.
  • High-point setback (A & C): pulls the high point off the property line into the lot (rear line in A, front line in C); the strip beyond it drains the other way. 0 = on the line.
  • Side FL layer: C-TOPO-FEAT-SWALE-LOT
  • Pad FL layer: C-TOPO-FEAT-PADS
  • Setback input layer: C-PROP-STBK (output of PARCELSETBACK)
  • Run report: per-lot CSV in the drawing's VDC Reports folder with coords, elevations, slopes, FL handles.

The two companions

  • VDCGRADELOTS_REFRESH, after the design surface moves. Re-samples the current design surface at every stamped feature-line frontage and re-slopes the sides and pad from it. Whole-drawing and no prompt, because it only ever touches feature lines this tool stamped. Chained first by VDCREFRESHALL.
  • VDCGRADELOTS_RESURFACE, the rename-recovery command. Each graded feature line's stamp records the names of its source design surface and its grading surface. Rename either surface and the stamps are orphaned, VDCGRADELOTS_REFRESH can no longer resolve them and stops working with no obvious cause. This lists every surface name the stamps reference, with counts, flagging any that no longer resolve; you type the stamped name and pick the surface it should now point at, and it rewrites the stamps only. Run VDCGRADELOTS_REFRESH afterwards to re-pull elevations. Also the way to intentionally repoint graded lots at a different design surface.

Dialog

Auto-Grade Lots dialog
Auto-Grade Lots, VDCGRADELOTS
VDCGRADELOTS_REFRESH, No dialog, runs on the whole drawing with no prompt.
VDCGRADELOTS_RESURFACE, Confirmation only, then runs on every feature line VDCGRADELOTS placed.
Settings file: %APPDATA%\VDC\AutoGradeLots\settings.json

When to use it

  • Early site work to get rough pads and balance before detailed grading.
  • After a surface update, to refresh pad elevations without regrading from scratch.

How to run it

  1. Run VDCLOTFRONT first so fronts are known (or be ready to pick fronts).
  2. Run VDCGRADELOTS and select the lots to grade.
  3. Choose the reference surface, the grading mode, and the slopes in the dialog.
  4. Choose the pad outline source: trace the setback polylines, or generate the pad from the lot (size + front setback, or front/rear/side setbacks).
  5. Review the pad feature lines and pad-elevation stamps that are created.
  6. Run VDCGRADELOTS_REFRESH after the surface changes to re-pull elevations - it runs across the whole drawing, no window step.

Options

  • Grading modes: A All-to-Road (drains to the road), B Split Front/Back (mid ridge), C All-to-Rear (front high point, drains to the rear).
  • High-point setback: Modes A and C - pulls the high point off the property line into the lot (off the rear line in A, the front line in C); the strip beyond it drains the other way. 0 = high point on the line.
  • Pad outline source: trace setback polylines (pick / auto-match), a generated rectangle (pad size + front setback), or the lot lines inset by front/rear/side setbacks - the generated modes are for when the drawn setbacks don't match the pads.
  • VDCGRADELOTS_REFRESH: surface-driven re-pull of pad elevations for already-graded lots, across the whole drawing - no window prompt (it only touches lots the tool graded).
  • VDCGRADELOTS_RESURFACE: reconnect grading to a renamed surface across the whole drawing in one pass - no window, every stamped feature line is reassigned at once.

Watch out for

  • Designate front edges first - grading orientation depends on the front.
  • Pick the correct reference surface; grading to the wrong surface yields wrong pads.
  • A generated pad that does not fit its lot (setbacks eat the lot, or the rectangle has nowhere to sit) is skipped and listed - shrink the size or setbacks and re-run those lots.
  • RESURFACE processes the whole drawing in one pass, reassigning every stamped feature line to the renamed surface at once - there is no partial run to finish.

Related: Lot Front · Pad Label · Label Feature Lines · Refresh All