Scaling Group Object Positions
Now you're prepared to make a direct comparison of how Position Scaling works with groups. To do so, you’ll leave the Sparrows Right Object’s position scaling to No Scaling, but you’ll set the Sparrows Left Object to scale position.
- Select the Sparrows Left Object and change the position scaling for X, Y and Z coordinates to Scale with space.
Now see what happens when you change to a larger Space.
- Switch the 32x32 Space.
See how the left group of Sparrows spread out relative to the parent group’s center?
- Switch to the 4x4 Space.
The left group of Sparrows is now tight and appears relatively the same compared to the Space size. The Sparrows Right Object has Spread out with two of the Sparrows even extending beyond the Stream Far Object.
- Switch back to the 8x8 Space.
Scaling Motion Paths
In addition to scaling Object size and position, you should also consider the scaling of motion paths. A motion path is somewhat like a group in that a single motion path contains multiple motion points, and those motion points' relative positioning can be scaled. For example, if a bird is flying in a 10 meter circular path, then should the size of that circle increase if the bird Object is placed into a larger Scene? Beyond that, you also have to consider if the speed of the bird’s flight should scale. For example, If it takes the bird 10 seconds to fly that 10 meter circle, should the bird still fly that circle in 10 seconds if the path was scaled up to a 20 meter circle? Again, this is a creative decision, but you have to give thought to this when you create these motion paths. To illustrate how this works, you’ll import a group object that contains four flying birds.
- Make sure the Scene Root Object is selected, then choose File > Import Object.
- Navigate to the Lesson 6 folder and choose the Flying Bird.splnode file and click Import.
You see 4 birds, two on the left and two on the right. Each bird has a linear motion path that will have the birds fly from the back of the room to the front in 5 seconds.
- Play the Scene.
What you should see now is a warning that certain assets can’t be found. Let’s use the relinking feature to ensure you have everything set.
- Click on Relink Assets
In this window you’ll see a list of assets which don’t exist in the Scene Project bundle.
- Click the box labeled Automatic Relinking.
- Now use the relink button on any of the files to open a finder window.
Inside the Lesson 6 folder, you’ll find a file called Flying Bird.opus. Select it. All of the assets should now be linked.
Let’s clean up our Canvas.
- Visually isolate the Flying Birds Object and turn on orthographic projection.
You see birds' flight paths. Currently they all move at the same speed. However, if you look at the settings for position scaling as well as motion path type, you’ll see each bird has a different combination of those two settings.
To understand the impact of these different settings, switch to the 32x32 Space.
- Switch to the 32x32 Space.
You see that two of the birds moved further outward from center and now have a motion path that’s 44 meters long. The other two of the birds remain the same relative distance from the center and are still traveling far. This is because the outer two birds have positional scaling set for all 3 axes. The motion points configured in the motion point list are part of that Object’s positional data, so they are also scaled when the Object is brought to a Space of a different size. This causes their flight path to be cut in half in length to around 25 meters. This also includes scaling the motion points distance to the origin point, which is why the Motion Paths of the outer birds both moved further outward. The inner two birds are set to No Scaling, so they retain the original flight path and remain the same distance to the origin point.
- Play the Scene.
Look at the speed of Flying Bird 1. He is flying seemingly slower than the other birds. This is because it was set to Duration, so this bird has to fly twice as fast to cover 25 meters in the same time it originally had to cover 44 meters. This is something to consider when using Motion paths on Objects that will be in Scenes deployed to spaces of varying size.
TIP: You can consider the Impulse type of Duration as the equivalent of scaling time, and an Impulse type of Velocity as representing no scaling of time.
Remember that if you set this Scene back to the original Medium Space that the Scene was developed in, all of the comparative Objects like the two streams appear to look or behave the same as their doppelgangers. However, when brought into a Space of a different size, huge differences can be revealed due to the condition of the settings discussed in this lesson. This is why it is strongly recommended that you think about how you want Objects to behave when they encounter differently sized spaces, and even better, test your Scene with different sized spaces to see if the Objects behave the way you want them to.