< Previous | Contents | Manuals Home | Boris FX | Next >
โSize Constraints โ
As well as the position and orientation of your scene, you need to control the size of the reconstructed scene. There are four general ways to do this:
๏ท With a distance (size) constraint between two points.
๏ท Have two points that are locked to (different) xyz coordinates, such as an origin (0,0,0) and a point at (20,0,0), as in the recommended three-tracker method described above,
๏ท From knowledge of the camera path (sometimes! carefully! if you know what you are doing!), or,
๏ท With an inter-ocular constraint for stereo shots .
If you want to use one collection of trackers to position and align the coordinate system, but use an on-set measurement between two other trackers, you can use a distance constraint.
Reminder : SynthEyes uses unit-less numbers. When you enter 20 units, you could call it 20 meters, 20 feet, 20 miles, etc. SynthEyes does not care; it is up to you.
Suppose you have two non-ZWT trackers, A and B, and for example want them 20 units apart. You set up the distance constraint as follows.
1. Open the coordinate system control panel.
2. Select tracker A, ALT-click (Mac: Command-click) on tracker B to set it as the target of A. In the coordinate system panel, you'll see tracker B's name now in the Target Point button. Note: if you have set the preferences to "no middle mouse button" then you must hold ALT/Command and right-click to link, since ALT/Command-left would be interpreted as a pan.
3. Set the distance (Dist.) spinner to 20. (You can remove a distance constraint by right-clicking the Target Point button.)
If you set up a distance constraint and have or will also use the *3 tool, use different trackers for the distance constraint and the *3 setup. Then, select the second point, which is locked to 20,0,0, and change its mode from Lock Point to On X Axis (On Y Axis for front/back setups). Otherwise, you will have set up two size constraints simultaneously, and unless both are right, you will be causing a conflict.
Tip : If you have solved or seed coordinates on the two trackers A and B, you can alt-shift-click B to set a distance constraint on A equal to the current distance between A and B. This is useful to create a distance constraint between the two when youโve already manually scaled the scene, and want to lock that scale in for the future.
Note that your size constraint does not do anything immediately: it is an instruction to the solver, and will have no effect until you solve or re-solve (ie in Refine mode) the scene.
You can set up coordinate systems with *3 and use those points for distance constraints, but you'll have to understand how to set them up directly, as described in the next section.
ยฉ2025 Boris FX, Inc.ย โย UNOFFICIALย โย Converted from original PDF.
