In this exercise we’ll explore three coordinate systems. Each one uses the same coordinates bar to enter the values.
Cartesian: X = X axis distance, Y = Y Axis Distance
Cylindrical: D = Distance A = Angle
Mapping: B = Bearing L = Length
Direct: / = Length Locked
By pressing the matching letter X, Y, D, A, B, L (and Z for 3D work) on your keyboard the cursor will move to the desired field and activate one of the coordinate systems. Let’s do that now.
You can ignore the ‘Z’ field at the moment as we’re not doing anything in 3D.
Did you notice the small letter ‘i’ next to those letters? – It indicates whether you’re in ‘incremental’ or ‘model’ coordinate mode.
If ‘i’ is showing, the values you enter are measured incrementally from (relative to) the last point.
If the ‘i’ is NOT showing then the values you enter will be measured from model zero which is where the origin of the Workplane currently resides.
Pressing i on the keyboard whilst a field is active will toggle between incremental and model coordinate mode for that coordinate field.
Pressing m on the keyboard whilst a field is active will toggle between incremental and model coordinates for all coordinate fields at once.
In the next three exercises we’ll produce the same drawing three times using three coordinate methods, Cartesian, Cylindrical and Mapping.
The idea is to get an understanding of how each of them operates so you can apply the most appropriate method to your own design technique.
By doing this exercise you’ll also know when not to apply a particular method.
When you have completed the three methods then try using the Direct Distance / Length Lock method.
Open the file in the Training folder called ‘Cool-Coordinates’. It should look like this.
A satellite image has been inserted and scaled to full 1:1 size. We’ve inserted three visual guides to the left of the drawing to indicate direction and angle depending on which coordinate system you’re using.
We’ll insert the outline of a building to be positioned in the vacant lot area ‘A’.
Phew. That was a marathon! For outlines containing many angled lines, the Cartesian method is NOT the preferred way. It is just plain hard work! This X and Y process works best when the lines follow the X or Y axis!
Let’s try a better method for this particular outline shape…
A line will be drawn at a length of 20000mm straight up the screen.
We’ll repeat the same exercise a third time only this time we’ll use Bearing and Length values. This is much the same as the previous method except the angle is calculated clockwise with zero being in the 12 O’clock (North) position.
Coordinates can be entered in various formats such as whole numbers, decimals, angles, bearings, Northings and Easting’s etc., let’s do one more drawing exercise using this same file, only this time we’ll draw the site boundary of one of the other lots, Lot B.
Architects, surveyors, landscape designers and many other professions will need to use this type of data entry.
We’ll start drawing from a fixed point that is 294.555 meters away from the Workplane origin in the X direction and 171.61 meters away from the Workplane origin in the Y direction.
The start of the first boundary line is now in place.
We are about to enter a bearing value of 66 degrees, 47 minutes and 16 seconds. To do this we must enter it in the following format where # = degrees and ‘= minutes
The software may convert the value you entered to a decimal angle value and be ready to accept the desired length value.
Repeat for all the boundary line values (You’ve already drawn line 1 so no need to re-enter it)
Select and Delete the protractor guides to reduce the file size and then use File, Save-as to save the completed drawing in your desired folder as ‘My Training Site’.
For the technically minded, rather than use the calculator you can also enter a mathematical expression in an edit field. Simply type an expression rather than a value.
Press the Tab key to see the result of the calculation before pressing OK to accept it.
See the manual for a list of mathematical expressions and functions you can use in numeric fields.
Note: You can use these in any dialog box numeric entry field, not just the coordinate’s bar.
The padlocks lock the current coordinate value and assist in drawing or editing in certain conditions.
Clicking on a padlock will toggle between a locked and unlocked state. Pressing ‘P’ on the keyboard whilst the field is active will also lock and unlock the padlock.
Perhaps the best use of the padlock is when you want to draw lines at multiples of a set distance but use your mouse to indicate direction.
Or padlock an angle value to force your movements to be in multiples of that angle.
In a similar way to the Shift key, the padlock allows the user to constrain and control movement, but when a Padlock is active the Shift Key works to temporarily unlock the constraints of the padlock.
When working in 3D, locking the Z value will force all lines to be drawn at the specified Z height.
Remember to un-padlock your coordinates when you have finished.