Traverse Recoverer

Traverse Recoverer — Help
User Guide · v1

Traverse Recoverer

A browser-based tool for assigning backsights and foresights to existing coordinate lists, then exporting a ready-to-import .rw5 data collector file.

01 Overview

Traverse Recoverer takes a list of known survey points (coordinates you already have) and lets you interactively reconstruct the traverse — defining which point was the instrument setup, which was the backsight, and which were foresights at each station. The result is exported as a Carlson/Sokkia-compatible RW5 raw data file.

No measurements are taken in the field. The tool computes angles-right and slope distances mathematically from the coordinates you provide.

Use case: You have a coordinate file from a previous survey, you need to reconstruct or re-create the raw data collection record (e.g., for staking, QA, or importing into Carlson SurvCE/SurvPC).

02 Loading Points

Points can be entered in two ways: pasting text directly, or loading a file.

Paste Coordinates

Type or paste your point list into the Coordinates text area on the left panel. Each line is one point. Supported formats:

FieldColumnRequired?Notes
Point Name1RequiredAny alphanumeric label
Northing2RequiredDecimal feet or meters
Easting3RequiredDecimal feet or meters
Elevation4OptionalIgnored in current version
Description5OptionalExported as -- comment in RW5

Columns may be separated by commas or tabs. Example:

1,5000.0000,5000.0000,,CP
2,5100.2300,5020.4400,,IP
3,5080.1100,5150.0000
4,5200.0000,5190.7700,,MON

Load from File

Click the 📁 Load Points button in the left panel to browse for a .csv, .txt, or .rw5 file. The file contents are read into the text area. Click Load Points in the action bar to parse them.

Note: Loading a new set of points clears any traverse work in progress. Use Export RW5 first if you need to save your work.

03 Traverse Workflow

After points are loaded, the Mode Indicator (top-left of the map) guides you through three repeating steps for each instrument station.

1
Click Next Setup Press the orange Next Setup button (or its pulsing prompt after load) to enter Setup mode. The mode indicator shows Click Setup as active.
2
Click the Setup Point on the map Click the point on the map canvas where the instrument was set up. It turns green to confirm selection. The status bar shows the setup point name.
3
Click the Backsight Point Click the point that was your backsight. It turns orange. A dashed orange line connects setup → backsight. The status bar updates with both names.
4
Click Foresight(s) Click any number of foresight points. Each gets a solid cyan line from the setup. You may click as many foresights as needed — there is no limit per station.
5
Advance or End Click Next Setup to close this station and start a new one, or End Traverse when all stations are complete. Once ended, the Export RW5 button becomes available.
Tip: You can add foresights to the same setup point over multiple sessions (as long as you haven't advanced to the next setup). Clicking an additional point in foresight mode simply appends it.

Undo

The Undo Last button steps backwards through the current station:

  • In foresight mode — removes the most recently added foresight. If no foresights remain, backs up to backsight mode.
  • In backsight mode — clears the backsight and returns to setup selection.

Undo does not affect completed (closed) stations from previous Next Setup steps. Use Edit Mode to modify those.

04 Background Image

A georeferenced image (aerial, topo, or plat scan) can be loaded and aligned to the survey coordinate system as a visual reference layer.

Loading an Image

Click 📁 Load Image in the left panel. Supported formats: .jpg, .jpeg, .png, .pdf, .tif, .tiff. PDF and TIFF files are rasterized automatically.

Aligning the Image

After loading, the Align Image dialogue appears at the top of the left panel. The process uses two control points:

❶
Click a recognizable spot on the image An orange crosshair marks the image pixel you clicked.
❷
Click its matching survey point Click the corresponding point in the point list to establish the first tie.
❸
Click a second spot on the image A cyan crosshair marks the second image pixel. Choose a point as far from the first as practical for best accuracy.
❹
Click its matching survey point Once both pairs are set, click Align Image to compute the geo-lock. The image renders at 55% opacity beneath the traverse.

Click Skip at any time to dismiss the dialogue without aligning. The ✕ Clear Image button removes the image and resets all alignment data. The ⚙ Align Image action bar button re-opens the alignment dialogue at any time.

The image pans and zooms with the map at all times once aligned — it is permanently geo-locked to the coordinate system.

05 Edit Mode

Edit mode allows you to modify foresights on completed stations. It becomes available once at least one station has been closed (via Next Setup or End Traverse) with foresights recorded.

Entering Edit Mode

Click the ✎ Edit button in the action bar. The button turns orange. Midpoint handles (small circles) appear on all foresight lines.

Selecting a Foresight

Click either the midpoint handle on a foresight line on the canvas, or click the corresponding entry in the Traverse Log. The selected foresight line turns red, and the Delete and Revise buttons appear.

Delete

Removes the selected foresight from its station entirely.

Revise

Replaces the foresight point. After clicking Revise, click any point on the map that is not the current setup or backsight. The old foresight is removed and the new one added in its place.

Editing Descriptions

While in Edit Mode, clicking any point in the point list or on the map canvas opens the Point Description dialogue, allowing you to add or change the description for that point.

Exiting Edit Mode

Click ✎ Edit again to toggle edit mode off and return to normal view.

06 Point Descriptions

Descriptions are short text labels attached to individual points. They are displayed in green beneath the point name on the map canvas, shown in the point list panel, and written to the exported RW5 file as a -- comment field.

Descriptions can be included in the original coordinate data (column 5) or added/edited at any time via the Description popup in Edit Mode. Maximum 40 characters.

08 Export RW5

Once the traverse is ended (or at any point with completed stations), click Export RW5 in the action bar. A prompt asks for a job name; this becomes the JB record and is used as the filename.

The file downloads automatically as <jobname>-MM-DD-YYYY.rw5.

SP Record Logic

The exporter automatically determines which points get SP (stored point) records:

  • All setup (OC) points and backsight (BS) points are always written as SP records.
  • Foresight-only points are written as SP records unless they do not appear as a setup or backsight anywhere in the traverse.
  • This mirrors typical data collector behavior — instrument stations and control points are stored; sideshots are not.

Computed Values

All measurement values in the RW5 are computed from the coordinates:

  • Backsight azimuth (BS record) — true bearing from setup to backsight, in DDD.MMSS.
  • Angle Right (AR field) — horizontal angle right from backsight direction to foresight, in DDD.MMSS.
  • Slope Distance (SD field) — horizontal distance in the coordinate units of the input file.
  • Zenith Angle (ZE field) — always written as 90.0000 (flat earth / no vertical component).

09 RW5 Record Reference

The exported file contains the following record types, in order:

JB — Job Header
Job name, date, and time stamp. Written once at the top of the file.
JB,NMMyJob,DT04-22-2026,TM14:30:00
MO — Mode
Instrument mode settings. Fixed values: Angle direct, US feet, scale factor 1.0, no EDM/EO corrections.
MO,AD0,UN2,SF1.00000000,EC0,EO0.0,AU0
SP — Stored Point
Coordinate record for a control or traverse point. Elevation is written as 0.0000. Description (if present) appears as a -- comment.
SP,PN1,N 5000.0000,E 5000.0000,EL0.0000,--CP
BK — Backsight
Defines the occupied point and backsight point with the computed azimuth. One per station.
BK,OP1,BP2,BS270.3045,BC0.0000
BD — Backsight Direct
The actual direct observation record to the backsight point (AR = 0, ZE = 90). Slope distance is computed from coordinates.
BD,OP1,FP2,AR0.0000,ZE90.0000,SD104.253
SS — Sideshot / Foresight
One record per foresight point. Angle Right and slope distance are computed from coordinates. Description appears as -- field.
SS,OP1,FP3,AR85.1532,ZE90.0000,SD151.420,--IP

10 Button Reference

Action bar buttons (bottom of canvas):

Load Points Parses the text in the Coordinates area and plots all valid points on the canvas. Clears any existing traverse.
Next Setup → First click: enters Setup selection mode. Subsequent clicks: closes the current station and starts a new one.
← Undo Last Removes the most recent action within the current station (foresight, then backsight, then setup).
End Traverse Closes the current station and marks the traverse as complete. Enables Export RW5.
✎ Edit Toggles Edit Mode. Active state turns orange. Only enabled after at least one station with foresights is closed.
Delete Visible in Edit Mode when a foresight is selected. Permanently removes it from the station.
Revise Visible in Edit Mode when a foresight is selected. Prompts you to click a replacement point.
Export RW5 Opens job name prompt then downloads the .rw5 file. Only enabled after End Traverse.
⚙ Align Image Re-opens the image alignment dialogue. Only enabled when an image is loaded.

Left panel buttons:

📁 Load Points Browse for a .csv, .txt, or .rw5 file and load its text into the Coordinates area.
📁 Load Image Browse for a JPG, PNG, PDF, or TIFF background image and trigger the alignment dialogue.
Clear All Resets everything — points, traverse, background image, and coordinate text area — back to the initial state.
✕ Clear Image Removes the background image and all alignment data. Traverse points are not affected.

11 Map Legend

Point Colors

Default — unassigned point
Setup (occupied) point for the current or any completed station
Active backsight point for the current station

Line Types

Orange dashed — backsight line (setup → backsight)
Cyan solid — foresight line (setup → foresight)
Red — selected foresight in Edit Mode

Mode Indicator (top-left overlay)

Step not yet reached
Current active step (glowing blue)
Step completed for this station

12 Tips & Notes

Point names: Any string is valid. Names that are purely numeric work fine and are common in survey files.
Multiple foresights per station: There is no limit. Click as many foresight points as needed before advancing.
Elevation: The current version treats all observations as horizontal (ZE = 90.0000). If vertical angles or elevations are required, post-process the RW5 in your data collector software or CAD package.
Scale factor: The MO record is written with SF = 1.00000000. If your project uses a combined scale factor, adjust it after import in Carlson or your preferred software.
Browser compatibility: Traverse Recoverer runs entirely in the browser with no server connection. Any modern browser (Chrome, Edge, Firefox, Safari) is supported. PDF and TIFF background images require an active internet connection for the rendering libraries.

Chatham Building Height LSP

CBH.LSP — Chatham Building Height Grade Plane Calculator AutoLISP tool for Carlson IntelliCAD

Overview

CBH.LSP automates the calculation of the Grade Plane elevation as defined by the Town of Chatham's building height bylaw. The Grade Plane is the weighted average elevation of the finished grade at the perimeter of a building, measured within 20 feet of the structure or to the property line, whichever is closer. This tool takes a closed 3D polyline representing that perimeter offset, breaks it into consistent slope segments, and returns a weighted average elevation — the Grade Plane — along with annotated drawing output and formatted report files.

Requirements

Carlson IntelliCAD with AutoLISP support. The tool has been developed and tested in the Carlson version of IntelliCAD. DIMSCALE must be set correctly before running, as the tool reads it automatically to scale tic marks and label text. The input polyline must be closed and must carry real Z elevation values — the tool will reject flat or zero-elevation polylines.

Installation

Load the file using the APPLOAD command or add it to your IntelliCAD startup suite. On load, the command line will confirm: CBH.LSP v7 loaded. Commands: CBH CBHSET (settings). The tool defines two commands: CBH and CBHSET. Global settings persist for the duration of the IntelliCAD session and reset to defaults on restart.

Workflow

Step 1 — Establish the offset perimeter. In plan view, offset the building footprint 20 feet (or to the property line if closer). Further modifications to this line are to be made to follow the low points. This becomes the measurement perimeter.

Step 2 — Set Z values from the surface. Using Carlson's surface tools, convert the 2D offset polyline to a 3D polyline by draping it over the existing or proposed grade surface. Alternatively, this can be completed with points, objects with Z values, or manually. The resulting 3D polyline will typically be a series of short line segments. If the conversion produces arc segments, CBH will automatically polygonize them into line segments before processing.

Step 3 — Set the layer. Place the 3D polyline on any layer. CBH will read the layer from the selected entity and place all tic marks and labels on the same layer automatically.

Step 4 — Set DIMSCALE. Confirm that DIMSCALE reflects your drawing scale (e.g., 20 for a 1"=20' drawing). CBH reads this variable on startup to size all annotation.

Step 5 — Run CBH. Type CBH at the command line. The prompt will display current settings and prompt for entity selection. Click the 3D polyline to begin processing.

What CBH Does

Once the polyline is selected, CBH performs the following operations automatically:

It polygonizes any arc segments into short chord segments. It reorders the vertices starting from the northernmost point (easternmost if tied) and winds clockwise. It groups consecutive segments into legs based on slope consistency — consecutive segments whose grade difference falls within the slope tolerance are merged into a single leg. It places a perpendicular tic mark at each leg break point, sized at 1/20th of the drawing scale on each side of the polyline. It places an MTEXT label at the true midpoint of each leg, on the polyline, aligned tangent to the segment and readable from the south. Legs are labeled A, B, C and so on. It computes the weighted average elevation across all legs, weighting each leg's average elevation by its 2D length.

Output

The Grade Plane result is always printed briefly to the command line. Additional output depends on the current Output setting:

Screen prints the full leg-by-leg report table to the command line.

Text saves a plain text report as a .txt file. The report includes layer, scale, slope tolerance, a table of legs with distance, average elevation, and the distance-times-elevation product for each leg, running totals, and the final Grade Plane.

HTML saves a formatted HTML table as a .htm file, suitable for opening in Word or Excel for use as an OLE object in the drawing or for submission to the Building Department.

All produces screen output plus both file types in a single operation.

When saving files, the dialog defaults to the drawing's current folder with the name BUILDING HEIGHT. Changing the base name in the dialog changes both the .txt and .htm filenames simultaneously — they are always written as a matched pair.

Commands

CBH — Runs the calculator. Displays current Slope Tolerance and Output settings on startup. Select the closed 3D polyline to proceed.

CBHSET — Opens the settings dialog. Prompts for a new Slope Tolerance value and Output format. Settings persist for the session.

Settings

Slope Tolerance controls how aggressively consecutive segments are merged into legs. The default is 0.005 ft/ft, equivalent to a 0.5% grade change. If a polyline with many closely spaced vertices is producing too many short legs, increase this value. If meaningful grade breaks are being merged, decrease it. Reasonable working range is 0.002 to 0.02.

Output Format controls where the report is sent. Options are Screen, Text, HTML, and All. Default is All.

Notes for Chatham Practice

The 20-foot offset perimeter should reflect post-grading conditions for proposed construction, or existing conditions for existing buildings. Where the 20-foot offset falls beyond the property line, the polyline should be clipped to the property line at those locations. Points of low grade within 20 feet that are not captured by the surface drape should be added manually as vertices with appropriate Z values before running the tool — the weighted average is only as accurate as the 3D polyline input. The slope tolerance default is conservative and will produce more legs on complex grade conditions, which generally improves accuracy of the weighted average.