Vertical profile and terrain surface

What it does

CAPCAD_PROFILE_MANAGER opens the CapCad Vertical Profile, the profile definition window. It does three independent things: generate the grade-line geometry from elevation data (Generate profile group), define which polylines of the drawing are an alignment's profile (Define profile group), and draw the defined profile with its annotations. It also erases the drawing, deletes the definition, frames alignment and profile, and leads to the profile analyses and to the auxiliary alignments.

CAPCAD_PROFILE_DRAW opens nothing: it takes the profile stored on the project alignment and draws its elements on the PROFILE_ALIGNMENT layer role — the name the active style resolved for that role. It is the PERF shortcut.

CAPCAD_SLOPE_QUERY asks for two points and writes the slope between them on the command line, to two decimals and always as an absolute value.

CAPCAD_SURFACE_MANAGER opens the Terrain Surface, a modeless palette holding a live surface in memory: you build it (from drawing points, from faces already drawn, or from a LandXML) and then cut sections and draw contours over it as many times as you like, without rebuilding.

Workflow

Generating the grade line from elevation data

1. Run CAPCAD_PROFILE_MANAGER. The project alignment must be defined.
2. Choose the source in the Generate profile group:
3. Online data (Bing Maps) (3): the alignment is walked every Step (8) metres and the elevation of each station comes from the elevation service.
4. Point list (6): the window widens and reveals the coordinates panel (36). Paste latitude, longitude, elevation — separated by TAB or comma, one per line.
5. GPS file... (5): the window closes and CapCad opens the geographic-data converter.
6. Set the Alignment distance limit (10): a point whose perpendicular projection on the alignment is beyond it is refused and goes into the failure report.
7. Click Elevation: place points (2). The drawing must have a coordinate system defined — both paths reproject.
8. The result is a polyline station × (elevation × exaggeration) drawn on the active style's GIS points layer (list) or Bing points layer (online), and the view is framed on it.
9. If Draw grid (13) is ticked, the grid and the planimetry are drawn with it.

That polyline is the drawing of the grade line. To make it data, use Define profile right after.

Defining an alignment's profile

1. Choose the mode in the Define profile group:
2. Use CAD coordinates (17): the drawing coordinates already are station × elevation. No anchor is stored.
3. Set initial values: (18): you give the Elevation (19) and the Start length (20) of the beginning of the profile, and CapCad stores the X and Y of the first vertex plus that station as the anchor.
4. Click Define profile ... (14). In initial values mode the command asks you to confirm the two numbers before any selection.
5. Select the alignment in the drawing.
6. Select the profile polylines. They must all run left to right; one running the other way stops the operation with the warning at the bottom.
7. In initial values mode, if the profile's length falls outside the alignment's length the command warns and asks whether to carry on (the excess is ignored).
8. The chosen polylines are rewritten onto the profile's GPS data layer and the definition is stored on the alignment entity.

Drawing the defined profile

1. Tick what you want: Curves (24), Grades (23), VPIs (25), Grid (26), Planimetry (27). At least one.
2. Click Draw (21) and select the alignment that carries the definition.
3. The grade texts come out at height 10, rotated in the direction of the gradient, with the value already divided by the Vertical exaggeration (29).
4. Erase profile (31) erases everything on the six profile layers — nothing to select.

Querying the slope between two points

1. Run CAPCAD_SLOPE_QUERY.
2. At the first prompt, either click point 1 or type Z to work from elevations.
3. Click point 2. The slope appears on the command line, as an absolute value to two decimals.

The normal path computes |100 × Δy / Δx| — the slope of the drawing. Over a drawn profile that is exactly the gradient; over the plan it means nothing. The Z path computes |100 × Δz / plan distance|, the real gradient between two elevations.

Building the terrain surface

1. Run CAPCAD_SURFACE_MANAGER. The palette opens on the Build TIN tab and the blue line at the top says there is no surface yet.
2. Build the surface one of three ways:
3. Build from points ▶ (44): select POINTs and/or blocks; with Prompt for breaklines (43) ticked, the command asks for the breaklines next. At least 3 points are needed.
4. From drawing… (45): select 3DFACEs or an already drawn mesh and CapCad reads the triangulation back.
5. Load LandXML… (58): opens a surface .xml.
6. The top line then shows how many points, how many triangles and the elevation range.
7. With the surface live, use the other two tabs: Cut section ▶ (52) asks for the cutting line and the profile's base point; Draw contours ▶ (57) draws straight away.
8. Save LandXML… (59) exports the live surface.

The surface is not stored in the drawing or in the project: it lives only while the palette is open.

The forms

The numbers are unique on this page: 1 to 38 in CapCad Vertical Profile and 39 to 60 in Terrain Surface. The screenshots are the Portuguese renders; the control positions are identical in every language.

CapCad Vertical Profile — CAPCAD_PROFILE_MANAGER

The window has two widths. It opens narrow and only widens when you tick Point list (6), revealing the coordinates panel on the right.

Factory defaults: online source, step 100, limit 200, CAD coordinates, exaggeration 10.

Generate profile group

Define profile group

Bottom row

Coordinates panel (only with Point list)

Below the list, three informational labels: the project's coordinate system, the number of lines typed, and Mostrando última tentativa when the contents were reloaded from the profile_gpspoints.txt file.

Terrain Surface — CAPCAD_SURFACE_MANAGER

The blue line above the tabs is the state of the live surface: Surface: N points · N triangles · Z min – max, or the notice that there is none yet. The three bottom buttons (58 to 60) apply on any tab.

Tab 1: Build TIN

Tab 2: Section

Tab 3: Contours

Bottom row

How the options combine

The three places a "profile" can live

This is the part that confuses most, and it is worth reading slowly. In this version there are three profile stores, and they do not talk to each other:

The practical consequence: defining the profile here does not make CAPCAD_PROFILE_DRAW draw it, and it does not feed the analyses. See Notes.

What the vertical exaggeration does in each operation

The profile is drawn at x = station, y = elevation × exaggeration — 10 by default, because a 3% gradient over a 2 km stretch would be invisible at the plan scale.

Where each thing is drawn

Where the table says role, the real layer name is whatever the active style resolved for it. Where it says literal name, the layer is created with exactly that name — see Notes.

How the section is sampled

In exact mode (47), the cutting line is intersected with every TIN edge and sampled at each crossing, plus its own vertices. Because the terrain is flat inside a triangle, that gives the exactly right profile, with the fewest possible vertices. The fixed step mode (48) is simpler and more predictable, but it cuts corners: a terrain break between two samples is lost.

A cutting point that falls outside the surface stops nothing — it gets elevation zero, and the section dives there. It is worth checking that the cutting line fits entirely inside the TIN.

Remembered between sessions

The CapCad Vertical Profile saves all its controls in the preferences — source, step, limit, exaggeration, definition mode and the drawing boxes come back as you left them. The point list is left out of that: it has its own file, profile_gpspoints.txt, written into the exports folder at every run of Elevation: place points and reloaded on the next opening, with the Mostrando última tentativa notice.

The Terrain Surface saves nothing: layers, colours, interval and exaggeration go back to the factory defaults at every opening, and the live surface dies with the palette.

Notes

• CAPCAD_PROFILE_DRAW has no ribbon button in any country profile. The command is reachable through the PERF alias or by typing the full name.
• The profile defined here does not feed CAPCAD_PROFILE_DRAW or the analyses. Define profile stores the definition on the alignment entity; CAPCAD_PROFILE_DRAW and the Civil 3D utilities read the profile from the project alignment; and the profile analyses want you to select the polyline at the time. All three paths use the same word for different stores. Use Draw (21) in this window for the profile you defined here, and keep CAPCAD_PROFILE_DRAW for the profile brought in from Civil 3D.
• The label at the top of the window looks at the other store. On opening, Profile set / Profile not set is read from the project alignment. After you click Define profile or Draw, it starts reflecting the selected entity. An alignment with a stored definition can therefore open the window saying Profile not set.
• Three of the profile drawing's layers have fixed names. Define profile, Curves, Grades and VPIs always create PROFILE_GPS_DATA, PROFILE_ANNO and PROFILE_ANNO_PIV, independent of the style, while Erase profile (31) erases the layers the style resolved for those roles. With a style that renames or prefixes layers, erase the three fixed-name layers yourself; with the default style the names coincide.
• CAPCAD_SLOPE_QUERY measures the drawing, not the terrain. Without the Z keyword it computes Δy/Δx in drawing units: it is the right tool over the profile, and you have to remember to divide by the exaggeration to get the real gradient. Over the plan, the number has no meaning.
• Two cancellations behave differently in CAPCAD_SLOPE_QUERY. Esc at the first point ends the command; Esc at the second makes the command report inclinação = 0.00 %. Two points on the same vertical (Δx = 0) also return 0.00 %.
• Not available in this version: Join points (12) — the generated points always become a single polyline —, Select polyline (22), Civil 3D surface (11) and Use Civil 3D (16).
• A few strings stay Portuguese whatever the interface language: the Mostrando última tentativa notice, the slope report (inclinação = 0.00 %) and the surface palette's status line and messages.
• The online elevation is an external service. A network or reprojection failure aborts the whole run — not even the points already processed are drawn. Progress is shown in blocks of 100 points and the bar can be cancelled.
• The refused-points report opens in its own window. The points that fell beyond the Alignment distance limit are listed as line ⇥ contents, so you can find the wrong row in the source spreadsheet.
• The terrain surface is volatile and its layers are typed by hand. Closing the palette discards the triangulation; fields 39, 50 and 55 create layers by the name you wrote, independent of the style: they get the colour typed beside them and no other property.
• A section only makes sense inside the TIN. A sampling point outside the surface comes in with elevation 0 instead of being dropped, which produces a step down to zero in the drawn profile.
• Contours create one layer per level. A small interval over broken terrain can create hundreds of CONTOUR_* layers. Check the Interval (53) before clicking.

See also

• Navigating the alignment — framing alignment and profile side by side and interlocating points between them.
• Draw and edit the alignment — the auxiliary alignments the profile is stored beside.
• Alignment Manager — the project alignment the profile is paired with.
• Station Navigator — reading elevation and gradient at a picked station.