At first glance the MoSpline object will probably have you scratching your head and wondering "Great, but what can I actually do with it?" Once you have played around with the parameters, the answer is Have a whole bundle of fun.MoSpline adds the fancy swirls at the beginning and end of the text spline by extending the spline
At first glance the MoSpline object will probably have you scratching your head and wondering "Great, but what can I actually do with it?" Once you have played around with the parameters, the answer is Have a whole bundle of fun.
The MoSpline Object creates a parametric spline which is controlled with data sliders instead of the usual spline points and handles. One of the main features of MoSpline is that it has its own built in version of a Radial Cloner. As with MoDynamics, MoGraph Effectors and certain Standard Particles Modifiers like Wind and Turbulence can be used with MoSpline. The Particles Wind Modifier by itself can give reasonable basic dynamic effects. The MoSpline can be used to create stylized floral objects or animated 3D Spirograph effects. The inclusion of additional Formula Fields for the parameters in the Simple Tab gives another option to create sequential parameter changes over the individual MoSpline segments. Simply adding a time multiplier (1+sin((ind/cnt)*360)*t) to the sample formulae shown in the Help file gives another level of animation which can create some hypnotic effects.
MoSpline is a complex object and we can't possibly explain and demonstrate all options and settings in this review. What we will try to do is cover the basics to get you started. The best way of learning MoSpline is to dive in and have a go yourself.
The practical use of MoSpline is as the main Path spline of a SweepNURBS object along with a suitable Profile spline. The profile works best with a parametric Spline Object, e.g. Circle Spline, Star Spline etc. The Width parameter in the MoSpline Simple tab gives direct control of the profile size, regardless of the Radius set in the Attribute Manager. This is a handy feature and would be a nice addition to the standard SweepNURBS Object. Once set up as the second child of a SweepNURBS (along with the profile), it is simply a matter of experimenting with the parameters to see how things are controlled.
On the Object Tab you have a choice of 2 modes: Simple Mode which has the MoSpline object generating its own spline or Spline Mode where you reference a normal spline. With both modes you have a lot of parameters that you can change to produce all kinds of weird and wonderful results. When you change to Spline Mode you get a Spline Tab where you can drag and drop the spline to reference. The Simple Tab settings are no longer relevant so this tab disappears. The following image demonstrates a MoSpline Object in Simple Mode.
MoSpline Simple Tab
Before carrying on, one thing you will almost certainly want to do is change the Display Mode on the Object Tab as the default option of Full Shape isn't actually that nice to look at. There are 3 settings to choose from and the idea is that in complex scenes you can get an idea of what the result (usually an animation) will be like but without enabling the SweepNURBS object as Viewport speed will be much quicker. Here's an image that demonstrates the 3 modes.
3 MoSpline display mode
The Dual Line and Full Shape modes estimate the width of the what the rendered SweepNURBS object will be like. In a simple scene you can change to Line mode and just have the SweepNURBS object enabled the whole time. One thing to note is that for accurate results the SweepNURBS 2 Rail option as described in the next paragraph needs disabling.
Yet another thing that you will want to do in virtually all cases when using a SweepNURBS object is in the SweepNURBS settings is to disable the 2 Rail option. The 2 Rail option is enabled by default but it causes the sweep to be flattened and the problem is exacerbated the more curves, bends and twists your MoSpline has. The image below shows this occurring on the MoSpline object on the right. The left MoSpline object has the 2 Rail option is disabled.
SweepNURBS 2 Rail option usually needs disabling
On the Object Tab in Simple Mode there are two options for the Grow Mode: Complete Spline where the segments are each swept sequentially, or Separate Segments where the segments are all swept at the same time. The following animation demonstrates the difference.
Left: Separate Segments Grow Mode. Right: Complete Spline Grow Mode.
The usual Start, End and Offset sliders are self explanatory and work similar to how they do on a SweepNURBS object. They are used to control the length and position of the actual sweep on the spline. The extra parameters for the Extend Start & Extend End are revealed by clicking the small arrows beside the keyframe buttons and can be used to add curls or spirals to the spline ends. Note that the Extend Start and Extend End features depend on the whether the beginning and end of the spline is straight or curved. If the main section is straight, then the extensions will also remain straight. The animated text at the top of this page uses the Extend Start and Extend End options (in the case of Simple Mode then the spline needs to be curved using the Curve and Bend settings on the Simple Tab). Because the text spline is curved the extensions are also curved and in this case created the swirls. Here are the settings on the Object Tab from the Text animation. The only thing that is animated is the End Growth parameter.
MoSpline Object Tab
To try and give you some understanding of what the Extend Start and Extend End options do, here is a comparison where the yellow text uses a MoSpline object with the settings in the previous image and the red text just uses the text spline. The Extend End settings are creating the swirl. You should note however that the MoSpline object is referencing the text spline.
MoSpline Extend End comparison
The base parameters of the MoSpline are set by the settings on the Simple Tab. Segments sets the number of Swept spline segments (cloned splines). At least one of the Angle (HPB) parameters is needed to fan out the individual segments. When any single Angle is set, the clones will be set radially in one plane. Mixing the three angles will create a more random array of clones.
The Curve, Bend & Twist parameters use Local Co-ordinates for angle calculations. This gives a progressive or cumulative step between each segment. There is an option to use the Global coordinates which will set the segments in a regular array. The following image shows the settings required on the Simple Tab to create this swirl type image. Also shown is the SweepNURBS settings as the Scale spline makes a big difference. A similar Scale spline has been used a in a few other examples on this page.
Simple Tab & SweepNURBS settings to create the swirls
As we mentioned in the introduction you can use MoGraph Effectors with MoSpline objects. If you have the MoSpline object selected, when you create an Effector it will be automatically added to the Effector Fields list. You will need to experiment using Effectors as some work better than others and not all things are supported. e.g. Random Effector - the colour mode used to colour clones is not supported. Similarly if you want to use Standard Particles Modifiers these are added to the Fields tab. On the Fields Tab there is an Include and Exclude mode option. If you don't exclude a Particle Modifier then it will be used by MoSpline object even without adding it to the Fields list. The image below shows the 2 tabs.
Effectors and Fields Tabs
Another practical feature of MoSpline is when used to generate an animated control spline for the MoGraph Spline Wrap. An empty Spline Object is used to reference and pass the MoSpline control parameters to the Spline Wrap simply by dropping it into the relevant spline fields.
As well as being used in SweepNURBS, the generated splines can be rendered using either Sketch & Toon (in spline mode)or HAIR. Hair material can be added directly to the MoSpline, in which case the spline will be "stroked" with the Hair. If MoSpline is used with a HAIR object, then the hair will be "grown" on the spline.
We have only scratched the surface with all that's possible with MoSpline. It's a lot easier to understand MoSpline by experimenting with it yourself rather than us trying to explain it in writing here. To give you taste of what's possible here are a few examples. Suggestion: Enable looping of your video player. Sorry about the large file sizes. There is a lot of action going on!!
Spirograph type animation - Click here to download and play the animation (QT 15mb)
Spirograph type animation (Perspective View)- Click here to download and play the animation (QT 16.8mb)
Same as previous animation (Top View)- Click here to download and play the animation (QT 19.6mb)
Flower animation - Click here to download and play the animation (QT 4.4mb)
Formula driven MoSpline - Click here to download and play the animation (QT 27mb)
Formula driven MoSpline - Click here to download and play the animation (QT 11mb)
Apart from the fun factor, I found the MoSpline Object a powerful tool for generating and animating a primary spline object. The level of control for an apparently random animation is quite amazing. I was impressed by the variety of animated sweep effects I was able to create in a short time using only MoSpline's parameters without any MoGraph Cloners and Effectors.
Well done MAXON for a seemingly harmless novelty which is really a bit of a wolf once you stir it up. 10/10.
Review by C4D Cafe © 2009