Dynamic Display - Operation & Navigation
To launch the Dynamic Display module, you click on the Open Animation button in the Results Tab of the Analysis component. When launched, the module automatically displays the animation for the currently selected stage.
To start an animation running, select the Animate – Play menu command or press the toolbar button. As the animation proceeds, the current animation time is constantly updated in the status bar.
If you want to suspend the animation at any time, select the Animate – Pause menu command or press the toolbar button. The Play button will be enabled when you do this, and you can use it to resume the animation.
To go back directly to the beginning of an animation, select the Animate – Rewind menu command, or press the toolbar button. You can then play the animation again, from the start. To jump directly to the end of an animation, select the Animate – Fast Forward menu command, or press the toolbar button. While an animation is suspended, you can resume in frame-by-frame play mode. This is done by selecting the Animate – Frame by Frame menu command, or by pressing the toolbar button. The animation plays forward one step, each time either of these operations is carried out.
While the animation is playing, you can change any display settings. You can also pan, rotate and zoom in on the structure. Further details are contained in the ‘Menu Bar Reference’ and ‘Toolbar Reference’ articles that follow.
The Dynamic Display module makes use of the DirectX capabilities to provide a control system capable of allowing precision inspection of models. It allows the user to move freely within a 3D environment and inspect any section of the model in detail.
There are two points of interest when navigating through the model. The Look At point and the Eye point. Both are three dimensional locations within the model. The Eye point is literally the position of our eye and the Look At point is the point we are currently looking at. The Look At point is always located at the centre of the screen.
A standard mouse with left and right buttons and a scroll wheel can be used to fully navigate through any model. The mouse buttons have two different control modes. If the Zoom Control toolbar button () is selected, the mouse buttons are used for zooming only. If the Zoom Control button is not selected, the mouse is in standard control mode. Note that holding down the ‘Ctrl’ keyboard button toggles the state of the Zoom Control.
For the standard control mode, the left mouse button is used to rotate about the current Look At point. The right mouse button pans the model in the current viewing plane. The scroll wheel is used to zoom in and out on the current Look At point.
When the left or right mouse buttons are held down, a red transparent sphere is drawn at the Look At point. The size of the sphere indicates how close the Eye point is to the Look At point. The screenshot below shows a rotation about the Look At point.
When the left mouse button is held down, a line is drawn from the centre of the red sphere to the cursor position (as shown above). The user can rotate the model about this point by dragging the mouse. The model can be rotated about all three axes (even though mouse movements are only in two). This is achieved by basing the rotation on both the direction the mouse is moving and the position of the cursor. Positioning the cursor close to the Look At point causes rotations about the Screen X and Screen Y axis. While positioning the mouse further away allows for rotations about the Screen Z axis.
When the right mouse button is held down, the red sphere is displayed along with a directional cursor, as shown in the screenshot below. Dragging the mouse pans the model in the direction of movement within the current viewing plane (i.e. the Screen X, Y plane). Note that when the user releases the right mouse button, a new Screen Z coordinate is automatically calculated for the Look At point, based on the nearest node.
Pushing the mouse scroll wheel forward moves the Eye point towards the Look At point (i.e. zooms in). Pushing the scroll wheel backwards moves the Eye point away from the Look At point (i.e. zooms out). Both movements are always along the Screen Z axis. Note that the Screen Relative axes use the right hand rule and are defined as follows:
▪Screen X axis is vertical (from bottom to top) along the screen.
▪Screen Y axis is horizontal (from left to right) along the screen.
▪Screen Z is directly into the screen.
In addition to moving the Eye point, the scroll wheel can also be used to move the Look At point. This is achieved by pushing the scroll wheel forward/backwards while either the left or right mouse button is pressed. This feature can be useful for navigating through areas where there are few model nodes (i.e. it allows the user to manually set the Screen Z coordinate of the Look At point) Note that this feature is only available while in Perspective view.
When the Zoom Control toolbar button is selected, the mouse can only be used for zooming in and out on the current model. The default cursor will be the zoom cursor (), while in this mode.
Pressing the left mouse button zooms in at the current cursor position. Pressing the right mouse button zooms out at the current cursor position. Both actions update the Look At point to be positioned at the cursor location. The mouse scroll wheel functions the same as in Standard Control mode, allowing the user to zoom in and out towards the current Look At point.
Pressing and holding the left mouse button, allows the user to drag the cursor over the area they wish to zoom. A dotted outline is drawn about the selected area, as shown in the screen shot below. Releasing the left mouse button zooms in to the specified extents.
In addition to using the mouse, the user can use the View Toolbar and a number of keyboard keys to navigate through the model. See the ‘View Toolbar’ section for more details.