User Guide
User Guide
User Guide
User Guide
User Guide
User Guide
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AccuDraw is a drafting aid that evaluates such parameters as your current pointer location, the previously entered data point, the last coordinate directive, the current tool's needs, and any directive you have entered via shortcut key-ins or AccuDraw options. AccuDraw then generates the appropriate precision coordinates and applies them to the active tool.
To help you understand what AccuDraw does, the following is a description of a simple design session using AccuDraw and the Place SmartLine tool. The task presented is the creation of a simple bracket. If a 3D file is used, the Top view is assumed in the exercise.
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The design subject is a simple bracket with the important dimensions and features noted. | |
With AccuDraw activated (Toggle AccuDraw tool in the Primary Tools tool box), select the Place SmartLine tool in the Linear Elements tool box. When you enter your first data point for the lower left corner of the bracket, AccuDraw displays a square or circular shaped “compass.”
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The AccuDraw compass appears whenever AccuDraw is active and a data point is placed. | |
Next, you need to draw the left edge of the bracket. As you move the dynamic line around the view window nothing interesting happens until you get close to one of the axes of the AccuDraw compass. In this case, because you want a vertical edge, you should move the line close to the Y axis. When AccuDraw senses the axis, the line snaps or indexes to it. While the axis is highlighted you can key in a number for the vertical distance, in this case, 2 inches. Don't worry about telling AccuDraw the direction, it has already figured that out and also has placed the input focus (where the key-in data will appear) in the correct field, in this case the Y field. After keying in the distance value, entering a data point results in what you would expect, a line segment oriented along the vertical axis and exactly two inches long.
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The start of the bracket's left edge with its 2 inch measurement courtesy of AccuDraw. | |
At this point the AccuDraw compass moves to the end point of the line you just placed. Moving the dynamic line segment around, it acts as before. This time you need to place the line with a fixed length of 1.25 inches in the horizontal direction. You do this by moving the dynamic line so that it snaps onto the positive horizontal axis, key in 1.25, and enter a data point.
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The bracket's top edge is taking shape as the indexed line is placed along the horizontal axis. | |
The next part of the bracket involves going off at a 30 degree angle for a given distance. Pressing the Space bar changes the AccuDraw compass to its polar mode (indicated by a circular compass), which lets you enter an angle and a distance. Entering 30 degrees in the Angle field and 1.75 inches in the Distance field locks the line in the right direction. A data point accepts the new location.
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The notch appears next with the Polar compass oriented along the new line. | |
Note how the compass orients along the 30 degree line. This illustrates AccuDraw's context sensitivity. AccuDraw provides a method for associating coordinate information with respect to existing elements. To place the half inch line at a right angle to the 30 degree line only requires indexing to the appropriate axis, keying-in 0.5 and entering a data point to accept.
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The notch is nearing completion. | |
With the bracket's notch complete, all that remains is the completion of the bracket's right edge. Currently, however, the compass still is rotated to the 60 degree angle of the notch and not the horizontal direction you need. To override the context nature of AccuDraw you press <T> to orient the compass to the Top view (the default). Pressing the Space bar brings up the rectangular compass. Indexing, again, to the X axis and keying in 2 inches followed by a data point locks the final known dimension of the bracket.
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A quick press of the <T> key and AccuDraw orients itself to the screen's x and y axes. | |
To “close out” the bracket's bottom edge, you use the smart axis locking feature of AccuDraw. Moving the pointer down the Y axis you press <Enter> for the smart lock feature. Recognizing that you are indexed along the Y axis, AccuDraw locks the Y direction but allows you to move up and down this axis. A tentative point on the beginning point of the bracket (the Place SmartLine tool allows you to snap to an element under construction) followed by a data point locates the lower right corner of the bracket. A final tentative point and data point on the origin of the bracket completes the job.
 | Remember that you can use AccuSnap in conjunction with AccuDraw. This speeds up the process of snapping tentative points. |
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A tentative point on the origin of the bracket results in the dashed index line. | |
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Accepting the tentative point completes the construction. | |
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An isometric depiction of the bracket construction shows the orientation of the AccuDraw compass upon the entry of each data point. | |
The preceding was a very simple example of AccuDraw in action. There is much more to this drafting aid. AccuDraw has been designed with ease of use and a certain intuitive feel to it. As with any drafting aid, you need to try it out first. As you get the hang of it, the various options begin to make sense.
In the following sections, the user interface features of AccuDraw are presented followed by the settings and directives that control its operations.
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By default, when MicroStation is started, AccuDraw is loaded automatically. With AccuDraw activated, all drawing tools utilize it for dynamic data input.
Normally, the AccuDraw compass does not appear until you enter the first data point after selecting a tool. AccuDraw's behavior changes slightly with tools that utilize dynamics before the first data point. The Place Text and Place Active Cell tools are examples of such tools. Instead of “waiting” for the first data point to display the compass, AccuDraw activates the compass at the last data point location. In this way, you can place the element with respect to this location by using any of AccuDraw's relative directives.
AccuDraw also affects operations like placing text or cells in another way. When you place a string of text with AccuDraw active, its initial orientation will be along the current AccuDraw drawing plane. In other words, when you have a Front-oriented drawing plane (see AccuDraw's drawing plane), the text will be oriented along the front axis regardless of the view orientation.
AccuDraw will not activate when it would conflict with other tools — for instance, during fence placement and element selection operations, dimensioning, and so on.
Although most users will activate and use AccuDraw during the entire design session, there may be times when its actions might interfere with the current operation. For this reason, AccuDraw can be turned off. MicroStation's tools return to their non-AccuDraw operation.
AccuDraw's most recognizable feature is its compass. Visible only when AccuDraw is active and has control of MicroStation's coordinate input, the compass acts as both a status indicator and a focus for your input.
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AccuDraw compass. Left: Rectangular coordinate system. Right: Polar coordinate system. | |
At the center of the compass is AccuDraw's origin point. This is the focal point of all AccuDraw operations. As you select various AccuDraw options, their functions operate from this origin point.
This last point is important. All AccuDraw directives (distance key-ins, shortcut key-ins, and so on) operate in conjunction with the compass. In most cases, the compass is located at the last entered data point. In addition, there are AccuDraw directives that allow you to move the compass to entirely different locations without generating a new data point. This is not unlike a tentative point.
Surrounding the origin point is the frame, or drawing plane indicator. Its primary purpose is to show the current orientation of AccuDraw's drawing plane and the current coordinate system in effect. When the frame appears as a dashed rectangle, the rectangular coordinate system (X,Y) is in effect. When the frame appears as a dashed circle then the polar coordinate system (Distance, Angle) is active. By default, the frame's color is gray but you can change this in the Display tab of the AccuDraw Settings dialog box.
When working in a 2D DGN file the drawing plane portion of the compass functions simply as an indicator of the current coordinate system. When working in 3D, however, the drawing plane becomes a much more valuable tool. Because you can orient the AccuDraw drawing plane along any plane in 3D space, AccuDraw's drawing plane indicator determines where your data points will appear with respect to the rest of the design.
 | You can relocate AccuDraw's origin to the current pointer location, or tentative point, using a shortcut key-in (the <O> key). |
The final parts of the AccuDraw compass are the two axes. Oriented at right angles to one another, these axes represent the drawing plane X and Y axes.
To differentiate between the two axes, each is color coded. By default, the positive or +X axis is displayed in red while the positive or +Y axis is green in color. If these colors do not suit you or are hard to discern, you can change them via the Display tab section of the AccuDraw Settings dialog box. As well, you can change the highlight color for when the pointer is indexed to the X or Y axes.
AccuDraw's drawing plane is central to its operation. As you work, AccuDraw orients this drawing plane based on a number of factors including cues from the active tool, the last placed coordinate, and key AccuDraw settings. This is known as context sensitive operation.
For instance, when you use the Place SmartLine tool, the orientation of the AccuDraw compass changes as you enter data points. Because Place SmartLine was designed to take advantage of the context-sensitive nature of AccuDraw, the tool cues AccuDraw to rotate the axis of the plane to the angle between the last two data points.
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Place SmartLine controls the orientation of the compass. | |
You can override this feature via the AccuDraw Settings dialog box (Operation tab section: Context Sensitivity check box off) in which case, the compass maintains the traditional view axes orientation (+X to the right, +Y straight up).
AccuDraw's drawing plane supports two different coordinate systems. This echoes MicroStation's normal support for rectangular and polar coordinate values:
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Rectangular, for specifying distances along the drawing plane axes. AccuDraw's frame appears as a square indicator.
Polar, for specifying distances and angles relative to the origin. AccuDraw's frame appears as a circular indicator.
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AccuDraw has its own window, named AccuDraw, which contains the data entry fields and axis lock buttons for the currently active coordinate system.
When AccuDraw is active it becomes part of the input focus order controlled by the <Esc> key. The focus order toggles between the AccuDraw window and the Tool Settings window unless the Key-in window is open. In this case, the input focus cycles from the AccuDraw window through the Tool Settings window to the Key-in window. Pressing <SHIFT-Esc> reverses the cycle, moving the focus from the Key-in window through the Tool Settings window to the AccuDraw window.
This is important to remember as no AccuDraw shortcut key-in works unless focus is in the AccuDraw window. Fortunately, after every data point or tentative point, the focus is forced to the AccuDraw window where it remains until you press the <Esc> key.
The AccuDraw window initially comes up floating just like any other window. However, it can be docked to either the top or bottom edge of the MicroStation application window.
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AccuDraw window docked along the bottom edge of the application window. | |
Docking the AccuDraw window has the advantage of minimizing its intrusion into the working area of your drawing. As with the floating window version, the fields found in the docked version change depending on whether you are in polar or rectangular mode and whether you are in a 2D or 3D DGN file.
Many aspects of AccuDraw's behavior are specified using the controls in the AccuDraw Settings dialog box. A few have already been mentioned (such as context sensitivity, and axis display colors).
| For information about other AccuDraw settings not covered elsewhere in this chapter, see AccuDraw. |
AccuDraw is controlled from a variety of sources. You can influence it through the use of one- and two-key sequences called shortcut key-ins. Drawing tools, themselves, can influence AccuDraw's operation. Finally, AccuDraw itself maintains a number of user selectable options via the AccuDraw Settings dialog box.
AccuDraw supports a large number of options, all of which can be placed into one of three major AccuDraw functions:
Previewing and constraining data points
Locating the AccuDraw compass
Orienting AccuDraw's drawing plane
The following discussion is organized along these three basic operations. In most instances, you will use a combination of all three types of AccuDraw operations to accomplish your design goal.
AccuDraw may be employed in a variety of different situations — with standard drawing and manipulation tools, or using more advanced approaches, such as with the Place SmartLine tool and the Modify Element tool. In either case, AccuDraw employs the same general procedure:
Select the desired tool.
Enter a data point to activate dynamics and set the location of the drawing plane origin. See The origin point.
If necessary, rotate the drawing plane axes. See AccuDraw's drawing plane orientation.
If necessary, set the type of drawing plane coordinate system. See Drawing plane coordinate systems.
Preview and constrain the next data point. See Previewing and constraining data points.
Enter the data point.
Typically, you will use a mix of AccuDraw options throughout the design process. The key to working with AccuDraw is understanding how it interacts with the active tool and the current data point.
| Many drawing tools are optimized for use with AccuDraw. See AccuDraw's Effect on Various Tools. |
| AccuDraw is particularly useful when employed in 3D. See Using AccuDraw in 3D. |
AccuDraw, via tentative points, lets you preview and constrain pending data point locations. In response to your input in the AccuDraw window, dynamic update in view windows lets you visualize the results. This gives you the option of accepting the displayed tentative point, or trying another location. That is, you have the flexibility to unconstrain a pending data point at any time. It is only when you actually enter a data point that you are committed to the values in the AccuDraw window and their results.
When active, AccuDraw reacts to pointer movement by trying to anticipate your intent.
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Moving the pointer (Rectangular coordinates). Top: Toward the x-axis; Bottom: Toward the y-axis. | |
As you move the pointer, the fields in the AccuDraw window automatically update to reflect the drawing plane coordinates of the current pointer location (expressed as either relative x, y, and z offsets, or as a distance and an angle) with respect to the location of the AccuDraw compass.
Furthermore, the AccuDraw window's input focus automatically adjusts, based on the general direction of the pointer movement. As you move the pointer in the same direction as either drawing plane axis the focus moves to the field that you would use to precisely locate the data point along that axis.
In the Coordinates tab section of the AccuDraw Settings dialog box is a setting for indexing tolerance for both Axis and Distance (instead of using Locate Tolerance from the Workspace > Preferences dialog box — although, by default, they are the same: 10 pixels). Alternatively, you can set this with a key-in (and therefore a shortcut or function key): ACCUDRAW SETTINGS INDEXTOL [num], where [num] is the number of pixels ranging from 1 to 100. This is useful when you want to do detailed work without it getting pulled back to the axes or to the last distance.
When the pointer is within the Tolerance of an axis, of the displayed AccuDraw compass, then the pointer snaps to the alignment of that axis. At this point, the dynamic element is considered indexed to that axis. Similarly, if the pointer is within the Tolerance of the previous distance, the pointer snaps to that distance.
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Index highlight along a drawing plane axis. | |
The effect of these behaviors is to make it as easy as possible for you to apply constraints and specify precision when previewing a data point.
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Keying in a precise distance along the x-axis. | |
When working with Polar coordinates, AccuDraw does not automatically shift the focus from the Distance and Angle fields like it does with the X and Y fields in Rectangular coordinates. Instead, you must navigate between these two fields to enter precise values. This is easily done using the <Tab> or <down arrow> keys.
When it comes to entering angular values, however, AccuDraw does try to help you out by not requiring a negative value when you want to go off in the “opposite” direction from an axis. Simply by moving the pointer to the opposite quadrant from the positive angle, AccuDraw moves the dynamic element in the negative direction.
Another example of how AccuDraw tries to help you is its previous distance feature. As you place elements in your model, AccuDraw keeps track of the distance between your last two data points. Known as the Previous Distance, AccuDraw uses this distance as a hint for your next data point.
Think of previous distance as a radius length from the compass origin. When you move the pointer within the Tolerance (see Locate Tolerance) distance to this radius, AccuDraw displays a small tangent line called the previous distance indicator, and locks the pointer to this point.
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Previous distance indicator. | |
As you keep the pointer within the Tolerance (see Tolerance setting) distance of this previous distance, AccuDraw will keep it locked. This, of course, only works with Polar coordinates. If you are using Rectangular coordinates, the previous distance only works when you are indexed to either drawing plane axis.
A data point will result in an offset distance from your last data point precisely the same as the distance between your previous two data points.
This “lock” on feature is not hard to override. Just continue dragging the pointer until it is outside the Tolerance and the previous distance lock disengages.
AccuDraw stores all entered values for its X, Y, Distance, and Angle fields for recall as needed. When in the X, Y, (Z in 3D), Distance, or Angle fields, pressing the <PgUp> key recalls the last distance or angle value entered in any of these fields. Pressing <PgUp> again recalls the next to last entered value and so on. You should note that the X, Y, Z, and Distance fields share a common value buffer but that Angular data is stored separately. This means you can enter a value in the X field, for instance, change the input focus to Y, and by pressing <PgUp>, enter the same value as placed in the X field.
Several AccuDraw settings that can be set in the AccuDraw Settings dialog box also can be toggled on or off with key-in commands. For instance, to turn on context sensitivity, you can key in ACCUDRAW SETTINGS CONTEXTSENS ON. If you enter it without trailing “on” or “off,” it behaves as a toggle. Being able to turn settings on or off is most useful for such things as macros, although you may want them as toggles in a function key/shortcut. These key-ins apply also to autoload, floating origin, auto point placement, axis indexing and distance indexing.
| The on/off option does not show up in the Key-in window |
With the pop-up calculator, you can perform mathematical operations on the values displayed in some MicroStation text fields and the values adjust accordingly.
| This feature is documented here as it works with AccuDraw. In fact, its use is extendable to other controls. For example, Active Scale and Active Angle fields currently support it. The pop-up calculator is supported as follows: |
Dialog Box |
Fields |
AccuDraw window |
X Y Z Distance Angle |
(various) |
Active Angle |
(various) |
Active Scale |
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Generating a calculated value (by typing “2+1”). | |
The pop-up calculator lets you perform calculations on measured values (snap to an element, then multiply the distance, for example), or to simply type in the entire equation, such as “5.23 + 1.34.”
Not only does the pop-up calculator eliminate the need to use a physical calculator, you may notice that with the “+” and “-” operations, you do not have to reposition AccuDraw's origin to move relative to a snapped or keyed-in offset.
The calculator is designed to be very efficient, to work seamlessly with AccuDraw, and to be entirely “keyboard-driven,” letting you keep the mouse in the view window rather than having to click in the dialog box. Also, the calculator works in a “per-keystroke” manner — the result of the calculation is expressed both numerically and graphically with every keystroke typed.
The pop-up calculator is “format aware,” as it accepts expressions in feet and inches or degrees-minutes-seconds, if appropriate. Obviously you cannot multiply feet times feet, so the calculator properly adjusts to interpret this type of string.
When performing operations on a measured value, the pop-up calculator always operates on the underlying precise value, rather than the string which is truncated to whatever coordinate readout you have. This dynamic value displays at the bottom of the pop-up calculator.
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Creating a relative offset (by snapping then typing “+2” when the X field has input focus). | |
| You may notice that sometimes pressing +, -, or / does not bring up the calculator, but is interpreted by AccuDraw as either an explicit positive or negative, or as a fraction. The rule with the “+” and “-” operators is: If the value is locked or a tentative point is active, the calculator displays. If you type something like “3 3/8,” the “/” is interpreted as part of a fraction because of the space. If you simply type “3/8,” AccuDraw uses the calculator but the result will be the same as 3 divided by 8, or the fraction 3/8. To enter “1 foot and 3/8 inches” you must type a space (“1: 3/8”) so the value is not misinterpreted as “1 foot 3 inches, divided by 8.” “1+:3/8” would also work. When entering planar data points (not polar coordinates), there are some special procedures to prevent unexpected results. Since AccuDraw interprets values as negative when the cursor is pointed in the negative direction, the calculator, when appropriate, prepends the entered expression with a minus sign. |
You can use the pop-up calculator to enter complex expressions, including multiple operators, parentheses, and C expressions (“sin(30)”, “tcb->actangle”). Parentheses do not have to be matched to have a valid string.
If you type =, the pop-up calculator replaces the existing AccuDraw value rather than operating upon it. In this case the result dynamically updates in the original field, rather than having a field of its own on the pop-up. This is rarely needed for simple operations, but can be useful for complex expressions.
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You can use the compact pop-up to replace values with expressions that do not contain a simple operator. | |
You can also enter and save variables. Although you cannot save them to a file, and there is no graphical user interface, this functionality can still be exceptionally useful. By default, the only saved variable is “pi.” The variable can then be entered within any expression using the calculator. To use the variable directly as a distance or angle, type “=<variable name>.”
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Entering a complex expression including parentheses and a user-defined variable. | |
Finally, there is a special variable, “$,” that represents the starting value, whether measured or typed into AccuDraw's field. For instance, if you measure a distance with AccuDraw and then want one over that distance, you can simply type “=1/$.” Or, for example, to get 12 squared, type “12*$.”
Although AccuDraw tries to anticipate your next move it cannot always predict your intentions. AccuDraw therefore includes a wide variety of single and double character command directives known as the shortcut key-ins. By pressing the appropriate key, you can direct AccuDraw to perform a specific task. In operation, AccuDraw is the default input focus in most cases, thus letting you just type in the shortcut without having to consider where the input focus is.
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Pop-ups confirm single letter shortcuts below the focused input field. This function is not only useful to confirm the key-in, but also it serves to communicate that the shortcut is received via AccuDraw's input fields.
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Two letter shortcuts appear attached to the focused input field, and confirm the action through the temporary appearance of the AccuDraw Shortcuts window. The pop-down list adjacent to the input field illustrates where the shortcut comes from, thereby making it easy to “follow the action.”
The following is a list of the more common shortcut key-ins:
Key |
Effect |
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<?> |
Opens the AccuDraw Shortcuts window. |
<Enter> |
Smart Lock
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<space bar> |
Switches between Rectangular and Polar coordinates. |
<O> |
Moves the drawing plane origin to the current pointer position. This can also be used to explicitly activate AccuDraw before you enter a data point. |
<X> |
Toggles the lock status for the X value. |
<Y> |
Toggles the lock status for the Y value. |
<D> |
Toggles the lock status for the Distance value. |
<A> |
Toggles the lock status for the Angle value. |
For the complete list, see Complete List of AccuDraw Keyboard Shortcuts.
There is a command to set the shortcuts back to the defaults, and one to reread the shortcuts file. The latter is useful if you want to change the file manually without exiting MicroStation. It could be useful, also, if you would like to alter the shortcuts programmatically (for example, with MDL or BASIC). Key-ins to perform these tasks are ACCUDRAW SHORTCUTS DEFAULT and ACCUDRAW SHORTCUTS READFILE.
As well as being able to edit the input fields in the AccuDraw window, you can create, edit, and delete, shortcuts in the AccuDraw Shortcuts window. In brief, you can:
Press <Delete> in any of the text fields in the AccuDraw window, which will let you edit, or delete, the string.
Delete a shortcut by highlighting it in the AccuDraw Shortcuts window and pressing <Delete>.
Create a new shortcut. When you do this, it will be inserted following the highlighted one, rather than being put at the end of the list.
Edit an existing shortcut.
When you create a new shortcut, or edit an existing one, a message box appears informing you if the shortcut is a duplicate or conflicts with an existing one (for instance, F and FS). You still can create it if you want to, which often is convenient if you want to edit the other one later, but if you click No, it returns you to the Edit/New Shortcut dialog box. If, for some reason, your edited shortcuts cannot be written to the “shortcut.txt” file, an error message will warn you of the situation.
One of the first keyboard shortcuts you will use is Smart Lock. Similar in operation to striking a line along a T-square, Smart Lock is invoked by pressing the <Enter> key. Depending on where the pointer is located, at the time you select Smart Lock, one of two things will occur:
If the pointer is oriented closer to the X axis of the compass, the pointer will lock to the X axis.
If the pointer is oriented closer to the Y axis of the compass, the pointer will lock to the Y axis.
You know the pointer is locked on an axis when the dynamic line highlights. Pressing the <Enter> key again deactivates Smart Lock and releases the dynamic line back to free motion.
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Positioning the pointer on a drawing plane axis — on the x-axis (above), on the y-axis (below). | |
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Constraining the pending data point along x-axis. | |
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Constraining the pending data point along y-axis. | |
| To disengage Smart Lock and unconstrain the pending data point, press <Enter> again. The <Enter> key toggles Smart Lock.
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| Smart Lock will not lock to an axis when you are entering coordinate values into its field. Instead, AccuDraw returns the dynamic element to free motion. |
When using the Rectangular coordinate system, you can force AccuDraw to lock the current distance along an axis by activating the <X> or <Y> keyboard shortcut. AccuDraw responds by locking the dynamic line to the chosen axis at the current pointer distance from the origin point of the compass. Having done this, the focus of the complement AccuDraw axis data field becomes the focus for your next keyboard entry.
| AccuDraw automatically switches its coordinate system to rectangular in response to the X or Y lock. All X and Y values entered are relative to the plane of the previous element segment. To override this, AccuDraw provides an option in its settings called Context Sensitivity. Turning this off forces AccuDraw to stay oriented to the DGN file's XY axes. |
You can use the <D> shortcut to lock the distance from the compass origin point to the current location of the pointer and, if necessary, change AccuDraw's coordinate system to Polar. The input focus automatically shifts to the Angle field.
You can use the <A> shortcut to set the angle portion of the polar drawing plane and, if necessary, change AccuDraw's coordinate system to Polar. AccuDraw sets the angle to the current position of the pointer.
| The Angle value automatically switches to the “opposite” angle if the pointer position dictates. |
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Angle value automatically switches to the “opposite” value. | |
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Angle value automatically switches to the “opposite” value. | |
Although you can set the X, Y, Z, Distance, and Angle fields by typing in values, AccuDraw also supports a roundoff feature that can force the new data point to a multiple of a set value. You can set AccuDraw's Unit Roundoff in the Coordinates tab section of the AccuDraw Settings dialog box.
When you enable the Distance field in Unit Roundoff, AccuDraw acts as if there is an invisible grid in effect. The Distance Roundoff, however, always is calculated from the current compass location. In addition, at any time you can override this value by snapping to an element, or entering a value in the X, Y, Z, or Distance fields of the AccuDraw window.
You can use the Angle Unit Roundoff to lock elements along specific axes. For instance, setting the Angle Roundoff to 30 degrees assures that all elements placed will occur along one of the normal isometric drawing axes. As with the X, Y, Z, or Distance fields, at any time you can override this value by snapping to an element, or entering a value in the Angle field of the AccuDraw window.
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Drawing in progress showing AccuDraw window with angle locked to 30°. | |
By default, AccuDraw places its compass at the last data point location. There are, however, times when you need to take over control of the AccuDraw compass. Tentative point operations can take better advantage of AccuDraw's capabilities when you “unlock” the compass and place it wherever needed. The following covers how you do this and some interesting ways in which you can use AccuDraw to accomplish otherwise difficult operations.
At any time, you can move AccuDraw's compass to the pointer location. You do this with the “O” keyboard shortcut, which forces AccuDraw to move the compass to the current pointer location.
This occurs regardless of the tool or operation currently selected. This last point is important to recognize. AccuDraw is considered a non-modal feature in that you don't have to be in a predetermined part of a procedure in order for it to operate.
In practice, the most common use for a relocated compass origin point is to index the element under construction from an existing point. For instance, if you want to locate the corner of a block a specified distance from a given location, you can tentative snap to the given location, then press O to move the drawing plane origin to the snap. From there you can use AccuDraw to position the tentative point from this relocated origin point. This procedure is explained in the following section on AccuDraw and the tentative point.
Creating precision offsets is a fundamental function of the design process. AccuDraw performs this important function by utilizing tentative points. These can be input manually, or you can further streamline the process using AccuSnap.
Whether you use AccuSnap or manually entered tentative points, the key to using AccuDraw and the tentative point is the Set Origin function (the <O> shortcut key-in). When there is a tentative point present, pressing the <O> key results in the relocation of the compass to the tentative point location.
AccuDraw enters a dynamic tentative point mode where you can manipulate the final data point location as follows:
Enter coordinate data using the AccuDraw window.
Use a second tentative point and various locks (X/Y or D/A) to interactively set the offset.
This latter technique is useful when you need to set an offset from two elements.
AccuDraw is a powerful tool in 2D drafting. It is even more powerful in 3D design, where you can work in a known coordinate system even though the view has a different orientation. For example, you can work in an Isometric view, with the AccuDraw drawing plane oriented in the Top View. AccuDraw orients the drawing plane in accordance with the Coordinate System Rotation setting in the AccuDraw Settings dialog box:
Coordinate System Rotation |
Definition |
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Top (default) |
Orients compass to match top view (in 2D same as an unrotated view). |
Front |
Orients compass to match front view (3D only). |
Side |
Orients compass to match side view (3D only). |
View |
Orients compass to current view axes. |
Auxiliary |
Orients compass to last defined auxiliary coordinate system (see Rotate Auxiliary). |
Context |
A temporary orientation affected by a number of factors including the current tool, the previous data points and the “RQ” keyboard shortcut. |
Along with the standard drawing plane orientations, the rotation of the drawing plane axes can be altered using keyboard shortcuts. In 2D, you are limited to rotating AccuDraw's drawing plane about the view axis. This matches the same restriction placed on rotating views in 2D.
Depending on the tool in use, dynamically rotating the drawing plane axes yields slightly different results. For example, consider the scenario of placing a block (rectangle) with the Place Block (Orthogonal) tool, which takes its orientation from the drawing plane XY axes.
Once the drawing plane axes are rotated, the block's main axis is constrained to the rotated XY axis.
Contrast this to the effect when using the Place Line tool: The drawing plane axes rotate, and while dynamic readout is a function of the newly rotated system, the tool itself remains available to dynamically place the line wherever desired.
You can use the Rotate Quick (<R>,<Q>) shortcut to change the orientation of the drawing plane only for the current data point, after which it resumes its normal orientation. This will vary, depending on the tool being used.
For example, suppose you are using the Place Line tool to start a construction and wish to align the drawing plane axes with the new line. After establishing the drawing plane origin (with the first data point of the line), pressing <R>,<Q> lets you rotate the drawing plane axes interactively.
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Dynamically rotating the drawing plane axes. | |
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Placing the line. | |
| Shortcut key-ins are available to rotate the drawing plane coordinate system 90° about an individual axis “RZ” (plus “RX” and “RY” in 3D) or to align it with the design plane axes “T” (plus “F” and “S” in 3D) or view axes “V”. When working in a 3D environment, AccuDraw's axes rotation takes on a very important role in the design process. This is discussed in Using AccuDraw in 3D. |
AccuDraw provides a few keyboard shortcuts to enhance popular tentative point snaps:
“N” — Nearest
“C” — Center
“I” — Intersect
These shortcuts work the same as selecting the snap from the status bar or Snap Mode button bar, with the exception of Nearest.
With AccuDraw disabled, when you snap to an element with the Nearest snap, either manually or with AccuSnap, MicroStation enters the tentative point at the point on the element closest to the pointer. With AccuDraw active, this changes a bit. When the pointer is constrained by either X, Y, Distance, or Angle Lock, and an element is snapped using Nearest snap mode, AccuDraw will attempt to produce a tentative point at the nearest point on the element that also satisfies AccuDraw's lock.
In many cases the effect is similar to that when using the Extend Element to Intersection tool. In the case where there is no point on the snapped element that satisfies AccuDraw's lock, the snapped point will simply appear at the point on the element closest to the pointer. This point will then be projected onto the hypothetical line or circle determined by AccuDraw's lock.
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Nearest snap with Place SmartLine tool constrained by an angle. | |
Although not technically a snap mode, there is one additional shortcut associated with tentative point snaps, “K” which opens the Keypoint Snap Divisor dialog box. This lets you define the number of keypoints in each element. When you use this shortcut, the following snap point is a Keypoint snap.
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Keypoint Snap Divisor dialog box | |
Although much of AccuDraw's operation is global in nature, it does have subtle effects on individual tools. As you learn to use AccuDraw you will find that it can be used as a substitute for many individual tool settings. The following discussion provides some insights into this feature.
The Place SmartLine tool is specially designed to exploit AccuDraw's capabilities. See AccuDraw and the Place SmartLine Tool.
A simple tool like Place Circle can benefit from AccuDraw in a number of ways. First, when you place a circle you can explicitly set the diameter of the circle by turning on the Diameter tool setting and entering a value. However, with AccuDraw active this can be done with fewer keystrokes.
Once you've placed the circle's origin point all you have to do is type in the radius value. AccuDraw automatically locks the circle to the value indicated by the locked dynamic circle. It really doesn't matter which drawing coordinate system is active.
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Using AccuDraw to place a circle by center. | |
To place a second circle of equal radius is also easy. Using AccuDraw's previous distance feature, when you move the pointer away from the center data point, the circle will temporarily lock to the previous radius letting you enter the second data point. This does require two data points for all remaining circles, so if you are placing numerous fixed diameter circles you may want to use the Diameter tool setting.
AccuDraw can be used to simplify the operation of the Place Arc tool. By using the polar coordinate system you can easily specify radial lengths and sweep angles just by typing them in via AccuDraw.
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Using AccuDraw to place an arc by center. | |
This is one case where AccuDraw's context sensitive orientation is good for incremental angle settings, and View or other rotations are good for setting an absolute sweep angle.
When you place an ellipse without AccuDraw you specify a center point, the primary axis and radius, and a point through which the ellipse will pass. You can do this by selecting the various options in the Tool Settings window or use AccuDraw to set these values in a more user-friendly manner.
When you enter that first center point, AccuDraw's effect becomes noticeable. The second data point still defines the major axis, but now you can specify both the radius and angle using the AccuDraw window simply by entering the radius and angle or dynamically positioning it.
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Using AccuDraw to place an ellipse by center and edge. | |
Now, because the AccuDraw compass orients itself along the axis of the ellipse under construction, the secondary axis is automatically locked so you can simply enter the value or position the pointer and data point.
You can use AccuDraw with the Place Block tool to place a block with specific dimensions and at a specific angle.
With the Rotated method you can specify the angle and X length of the block using the polar drawing plane. Once the base of the block has been defined, AccuDraw orients the compass along this base. At this point, you can switch to rectangular mode (space bar) and lock in the Y distance by simply entering its dimension.
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Using AccuDraw to place a block | |
The Place SmartLine tool is used to automatically place a complex chain or shape containing a dynamically specified collection of segments and vertices. This tool is designed to be used in conjunction with AccuDraw. The main benefits of using AccuDraw with Place SmartLine are as follows:
The drawing plane origin automatically moves to the location of a newly defined vertex.
The drawing plane automatically rotates to align with a newly defined segment. This allows tangent and perpendicular segments to be easily defined.
When defining an arc segment, the drawing plane coordinate system automatically switches to Polar.
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Switching the Place SmartLine Segment Type to Arcs. | |
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Defining the center point. | |
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Defining the sweep angle. | |
| You can key-in values for the Radius and the sweep angle, using AccuDraw's input fields. As well, the arc's sweep angle can be defined in either direction — clockwise or counterclockwise. |
The tools just described were selected to illustrate how AccuDraw works with even the simplest tools to provide additional capabilities, or easier access to options, over non-AccuDraw operations. AccuDraw actually affects the operation of most MicroStation tools, and even has the potential to work with third-party application software.
The following table lists each keyboard shortcut and its effect. Additional information about the effect of individual keyboard shortcuts is presented in the general discussions of AccuDraw procedures.
Key |
Effect |
|---|---|
<Enter> |
Smart Lock
|
<Space bar> |
Switches between Rectangular and Polar coordinates. |
<O> |
Moves the drawing plane origin to the current pointer position. |
<V> |
Rotates the drawing plane to align with the view axes (see Orienting the drawing plane in 3D). Pressing this key a second time restores context-sensitive rotation. |
<T> |
Rotates the drawing plane to align with the axes in a standard Top view (see Orienting the drawing plane in 3D). Pressing this key a second time restores context-sensitive rotation. |
<F> |
Rotates the drawing plane to align with the axes in a standard Front view (see Orienting the drawing plane in 3D). Pressing this key a second time restores context-sensitive rotation. |
<S> |
Rotates the drawing plane to align with the axes in a standard Side view (see Orienting the drawing plane in 3D). Pressing this key a second time restores context-sensitive rotation. |
<B> |
Rotates the drawing plane to align with the active ACS, or if you set up a rotation in the dialog, it will return you to that rotation. In a new file (where you haven't used an ACS yet) it will be the rotation of the view. |
<E> |
Rotates between three main planes: top, front, and side (3D only). This also works when your original plane is an ACS or context rotation, so you do not have to use RX, RY to rotate to a 90° plane. |
<X> |
Toggles the lock status for the X value. |
<Y> |
Toggles the lock status for the Y value. |
<Z> |
Toggles the lock status for the Z value (see Using AccuDraw in 3D). |
<D> |
Toggles the lock status for the Distance value. |
<A> |
Toggles the lock status for the Angle value. |
<L> |
Locks the current index state. If an axis or distance is not indexed, indexing is disabled. On the other hand, if an axis or distance is indexed, it is locked. The effect is temporary, lasting until a data point is entered or the shortcut is run again. This is useful if you need to index to one axis but not the other, or to enter a data point very close to an axis but not on the axis. |
<R>,<Q> |
Used to quickly and temporarily rotate the drawing plane. The procedure is described in The Rotate Quick keyboard shortcut. |
<R>,<A> |
Used to permanently rotate the drawing plane. Because it rotates the current ACS, this rotation will still be active after the tool in use is exited. If on, the tool setting Use Current Origin causes the drawing plane origin to be used as the x-axis origin, thereby eliminating the need to enter an extra data point. Of course, in many cases it is desirable to be able to define the x-axis origin at a different location than the drawing plane origin. |
<R>,<X> |
Rotates the drawing plane 90° about its x-axis (see Orienting the drawing plane in 3D). |
<R>,<Y> |
Rotates the drawing plane 90° about its y-axis (see Orienting the drawing plane in 3D). |
<R>,<Z> |
Rotates the drawing plane 90° about its z-axis. |
<?> |
Opens the AccuDraw Shortcuts window. |
<~> |
Bumps an item in the tool settings dialog box (shortcut is ~, usually right under the <Esc> key — there is no need to press the <Shift> key). It finds the first enabled item in the tool settings dialog box that is a toggle button or an option button, and either toggles it or bumps it to the next valid value. For instance, if you are drawing a SmartLine and the focus is in the AccuDraw window, you can just press the <~> key and it switches to arcs without moving the focus from the AccuDraw window. Key-in: ACCUDRAW BUMP TOOLSETTING. |
<G>,<T> |
Moves focus to the Tool Settings window. |
<G>,<K> |
Opens (or moves focus to) the Key-in window (same as choosing Key-in from the Utilities menu). |
<G>,<S> |
Opens (or moves focus to) the AccuDraw Settings dialog box (same as choosing AccuDraw from the Settings menu). |
<G>,<A> |
Opens the Get ACS dialog box, which lets you select a saved Auxiliary Coordinate System. |
<W>,<A> |
Opens the Write to ACS dialog box, which lets you save the drawing plane alignment as an ACS. |
<P> |
Opens the Data Point Key-in dialog box for entering a single data point. See Precision Input Key-ins. |
<M> |
Opens the Data Point Key-in dialog box for entering multiple data points. See Precision Input Key-ins. |
<I> |
Activates Intersect snap mode. |
<N> |
Activates Nearest snap mode. |
<C> |
Activates Center snap mode. |
<K> |
Opens the Keypoint Snap Divisor dialog box, which is used to set the Snap Divisor for keypoint snapping. |
<U> |
Suspends AccuSnap for the current tool operation. Selecting a new tool, or entering a Reset re-enables AccuSnap. |
<J> |
Toggles AccuSnap. |
<Q> |
Deactivates AccuDraw. |
| Keyboard shortcuts are not case sensitive. |
