You can use fly pasts to control the movement of the camera during timeline simulations. A fly past consists of a series of viewpoints - "fly past points" - which are each applied at a particular point in time during a timeline simulation. For example, you could configure a fly past to start with the camera pointing at the front of a building, then move to particular areas of the building that are being constructed at different points in time, showing these areas in greater detail.
Each fly past point can be associated either with a particular date or with the start or finish date of a particular task. Associating fly past points with particular dates would enable you to create a fly past that showed the weekly or monthly progress of a project, with a fly past point associated with the start date of each week or month; associating fly past points with the start or finish date of a particular task would enable you to create a fly past that zooms into objects in an IFC model that are associated with particular tasks at the point at which they are started or finished. A fly past can contain both types of fly past point.
Creating fly pasts
To create a fly past:
- Open the IFC model or IFC group model for which you want to create a fly past in the IFC Model pane.
- On the BIM tab, in the Timeline Export group, click the Fly Past dropdown and select New. The IFC Model Fly Past Properties dialog appears.
- Enter a descriptive name to identify the fly past in the Name field.
- Add a fly past point to the grid as follows:
- Arrange the display of the IFC model or IFC group model in the IFC Model pane as you want it to appear at the fly past point. Fly pasts can include fly past points with viewpoints in a mix of both orthogonal and perspective mode.
- Click Add. A new fly past point row appears in the grid on the dialog.
If you select an existing fly past point before clicking Add, the new fly past point is added immediately below the selected fly past point; otherwise it appears at the end of the list of fly past points.
- Click the row in the Point name column and enter a descriptive name to apply to the fly past point; if you are going to associate a task with the fly past point, you may like to leave the name blank for now.
- In the Fly past point type column, specify whether the fly past point is to be associated with a particular date, or with the start or finish date of a particular task.
- If the fly past point is to be associated with a particular date, enter the date in the Fly past date column.
- In the Transition column, specify whether the fly past should fly smoothly or snap abruptly to the fly past point when the date is reached.
- If the fly past point is to be associated with the start or finish date of a particular task, with the fly past point row selected in the grid, select the task in the bar chart and click Set Task. The task's start or finish date and name appear in the Fly past date and Fly past task columns in the dialog and its name appears in the Name column too, unless you have already specified a name for the fly past point.
- Repeat the above step as many times as necessary to create all of the fly past points that you need.
- If you need to change the viewpoint of a fly past point, arrange the display of the IFC model or IFC group model in the IFC Model pane to the viewpoint that you want then select the fly past point in the grid and select Update Viewpoint.
- If you select the Track selected fly past point in the IFC model pane check box, the display of the IFC model or IFC group model in the IFC Model pane is updated automatically to the viewpoint of the fly past point that is selected in the grid. Selecting this check box may make it easier to visualise a fly past as you are creating or editing it, although it has no effect on the finished fly past itself.
- Click Close. The fly past is created and saved in the IFC Model Fly Past library in Library Explorer.
If you need to create a fly past that includes a large number of fly past points, you may find it useful to take snapshots of all of the fly past point viewpoints before creating the fly past. You can then switch the display to the snapshots in turn, while creating a corresponding fly past point for each one.
Applying a fly past to timeline simulations
To apply a fly past to timeline simulations in the IFC Model pane, on the BIM tab, in the Timeline Export group, click the Fly Past dropdown and select the fly past that you want to apply. The fly past that you select is highlighted with a tick and will be used the next time you run a timeline simulation - either by clicking or by using the control.
If the IFC Comparison Model pane is displayed, you can choose whether to apply fly pasts to this pane as well as to the IFC Model pane. To apply fly pasts to the IFC Comparison Model pane, on the BIM tab, in the Timeline Export group, click the Fly Past dropdown and select the Show on Comparison Model. The command is highlighted with a tick.
Select this command again to apply the selected fly past to the IFC Model pane only. The tick is removed from the Show on Comparison Model command.
Turning off all fly pasts
To turn off all fly pasts, on the BIM tab, in the Timeline Export group, click the Fly Past dropdown and select None.
Editing the properties of a fly past
Once you have created a fly past, you can edit its properties. You may want to do this to edit its name or to amend its fly past points.
To edit the properties of a fly past:
- On the BIM tab, in the Timeline Export group, click the Fly Past dropdown and select the fly past that you want to edit.
- From the same drop-down, select Properties. The IFC Model Fly Past Properties dialog appears, listing the fly past points in date order.
- Edit the fly past as required as described above, then click Close.
Fly pasts and IFC group models
If the IFC Model pane is currently displaying an IFC group model, any fly pasts that you create relate to the IFC group model and are visible in the Fly Past dropdown only when the IFC group model is displayed.
If the IFC Model pane is currently displaying an IFC group model and you have created fly pasts for one or more of the individual IFC models in the IFC group model, the Fly Pasts dropdown displays the fly pasts that have been created for all of the individual IFC models, as well as any fly pasts that have been created for the IFC group model itself.
- It is not possible to fly smoothly between a fly past point with an orthogonal point of view and one with a perspective point of view. If adjacent fly past points have viewpoints that have been taken in different modes (ie one is orthogonal and the other is perspective), the transition between the two will always be an abrupt snap, regardless of the transition that you select.
- If a fly past contains more than two fly past point with the same date, those fly past points "in the middle" are ignored and their viewpoints are never displayed.
- If a fly past point is associated with a task and the task is then deleted, the fly past point itself is not deleted, but it is ignored and its viewpoint is never displayed.