Bearings and Angles¶
Bearing convention¶
R3Survey uses whole-circle bearings (also called azimuth or grid bearings) measured clockwise from north:
- North = 0° 00' 00"
- East = 90° 00' 00"
- South = 180° 00' 00"
- West = 270° 00' 00"
This matches the convention used in Australian survey practice and NSW LandXML.
Bearing formats¶
R3Survey supports three bearing input systems. The active system is selected on the Angles tab of R3UNITS.
Decimal DMS (North Azimuths)¶
The default format. Degrees, minutes, and seconds are written as a single number — DDMMSS — where the decimal point separates degrees from minutes and seconds:
DDMMSS → D°M'S"
| You type | Means | Notes |
|---|---|---|
45.3020 |
45° 30' 20" | |
180.0000 |
180° 00' 00" | |
90 |
90° 00' 00" | |
.52 |
0° 52' 00" | Leading zero optional |
0.5230 |
0° 52' 30" | |
315.30 |
315° 30' 00" | Trailing zero required — 315.3 is invalid |
359.5959 |
359° 59' 59" |
Minutes without seconds
When entering minutes without seconds, the trailing zero is required. 125.30 means 125° 30' 00"; 125.3 is rejected.
Minutes and seconds must each be in the range 0–59. 45.6100 (61 minutes) is rejected.
Surveyor's Bearings (Quadrantal)¶
Bearings expressed as angles measured from north or south toward east or west — the traditional surveying notation used on older cadastral plans. Enter a quadrant number (1–4) followed by the angle:
| Quadrant | Direction | Example input | Displayed as |
|---|---|---|---|
1 |
North-East | 129.3020 |
N 29° 30' 20" E |
2 |
South-East | 210.30 |
S 10° 30' 00" E |
3 |
South-West | 310.30 |
S 10° 30' 00" W |
4 |
North-West | 410.30 |
N 10° 30' 00" W |
Cardinal and intermediate directions can be entered by name:
| Type | Means |
|---|---|
N |
North (0°) |
E |
East (90°) |
S |
South (180°) |
W |
West (270°) |
NE, SE, SW, NW |
45°, 135°, 225°, 315° |
Internally, R3Survey converts all Surveyor's Bearings to whole-circle bearings before drawing.
Gradians (Gons)¶
A gradian (or gon) divides a full circle into 400 increments rather than 360 degrees. Enter as a plain decimal number:
| You type | Means |
|---|---|
210.7184 |
210.7184 g |
379.9575 |
379.9575 g |
100 |
100 g (= 90°, due East) |
400 |
400 g (= 0°, North — same as 0 g) |
Gradians are common in European survey practice and some older instruments.
Swings¶
If a swing is active, entered bearings are automatically adjusted before being applied. The swing is a stored angular offset that aligns your bearing system with the drawing coordinate system. See Swings.
Bearing display¶
In R3PROPERTIES, bearings are shown in the format configured in R3UNITS. The display format (Compact, Spaced, or Decimal) and the angle units (North Azimuths, Surveyor's Bearings, or Gradians) are set independently.
Examples for the same bearing (45° 30' 20"):
| Format | Example |
|---|---|
| Compact DMS | 45°30'20" |
| Spaced DMS | 45° 30' 20" |
| Decimal | 45.3020 |
| Surveyor's Bearings (Compact) | N45°30'20"E |
| Gradians | 50.617 g |