Reference Material

Collision Tab
- Collision Detect — reflects the influence of other objects upon the motion of an object. This lets you create complex motions caused by obstacles. The simulation is performed by taking an object that collides (the collision object) with the elastic body model (dynamic object) into the calculation.

- Exclusive Collision — Selecting an item from this list will exclude all other collision objects from the calculation.

- Interaction — By Default you would want Interaction set to “All” so that All geometry with interact with each other. However you have the option of limiting the interaction by Vertex Maps .

- Collision Offset — By default the collision offset is set to 0 so that the collision object will collide with the surface of the target object allowing the target object to deform. Increasing the Collision Offset will result in the collision object deforming the target object at the distance specified in the collision offset field.

- Friction — Like real world friction, the Friction parameter makes the surface less slippery. So if you want the Dynamic object to tend to slip off the collision object, set Friction to 0. If you want it to stick more, increase the value.

- Connected — If you activate “Connected” it will treat each set of Contiguous points as separate objects that collide with themselves.

- Self Collision — The Self Collision setting can prevent an object from crossing itself when the object is transformed. Self Collision is calculated based on a point on the target object and a polygon on the collision object. If a surface has Self Collision and Collision Detection active, Self Collision is computed on the same surface.

- Double Side — Collision Detection is detected even if the motion is from behind the polygon.

Advance Tab
- Resistance Mode — Resistance mode tells the Resistance setting in Basic Tab how to react. With some Resistance you can see as you change Mode settings how the polygons will resist wind effects.

- Polygon (front) — points facing the wind move based on wind direction + point normal.

- Polygon(back) — points facing away from wind move based on wind direction + point normal.

NOTE: Resistance settings only apply to wind.

- Mode Ratio — sets the amount of Resistance applied to specific effects set by Resistance Mode versus standard. 75% sets 75% of the Resistance Mode and 25% of the standard resistance.

- Compress Stress — controls the amount of compression a surface exhibits as a result of stress. A soft fabric like cotton can be made using a large Spring value and a low Compress Stress setting. A stiffer fabric would use a higher Compress Stress setting.

- Stretch Limit — To prevent a surface from stretching like rubber, lower the Stretch-limit below the default value of 100%. This restricts the amount of the surface to be stretched.

- Polygon Size — Changes the surface to a specified size. For example, a value of 90% reduces the size of the surface to 90%. Use Polygon Size to reduce the looseness of a dress or to create frills.

- Fiber effect — Allows you to set an axis for the traditional Fiber effect , basically making a certain axis “stronger” than the others. For example, setting Y makes the built-in folds of the dress (dress_ fx002) stronger so the folds aren’t disregarded during calculation.

Etc Tab
- Gravity(m/s^2) — Specify the direction and intensity of gravity along the world axes.

- Resolution — Set the accuracy of calculation by how big the maximum error is. When it approaches 0 the accuracy increases and errors will decrease, but calculation amount will also increase so it will take more time to calculate.

- View Feedback — Set the feedback in Layout when controlling Cloth FX. When the display is poor or the display speed is slow, you uncheck this.

- Numeric Feedback — Set the numerical feedback in Layout when controlling Cloth FX. When the display is poor or the display speed is slow, you uncheck this.

- Presets — Similar to surface presets, Cloth FX has 5 built in presets that give you a good place to start. Presets include: Cotton Thin, Cotton Thick, Silk, Rubber, Jelly.

- Save Motion — saves the generated motion to a file, which will be used subsequently to deform the object.

- Load Limit — Loads Limited Frames. Example : If you have a MDD file with 2000 frames of data you can limit it to just 100 frames to make it less processor intensive.

- Playback Mode
Normal — Plays back all Motion settings of the .mdd file.
Local — Plays back based on the local translations (move rotate and scale) of the object. Allows an .mdd deformation on an object while respecting new motion applied to that object.
Distance Map — Adjusts the motion data to the movement of object. When speed is 100%, 1s (second) animation is played back concerning the movement of 1m.
Speed — When Playback Mode is set to Local or Distant the user is able to control the playback speed.
Node Match — When Node Match is activated, the motion data can be played back on the object’s local position.
Shift Frames — The user can shift the time the motion starts. Use Shift Frames if you need the motion to start on an earlier or later frame.
Loop — The user has the option to loop the motion file in two ways.
Repeat — Plays the motion from start to finish and then repeats the motion from start to finish continually.
Oscillate — Plays the Motion from start to finish and then plays it from the end frame backwards to the start frame and then repeats. (Ping Pong motion)
Motion Size — Motion Size increases the distance relationship between points in a motion file.
Copy — Use the Copy button to copy the current settings between dynamic objects.
Paste — Use the Paste button to paste the current settings between dynamic objects.
Save — Saves all the settings contained in the Cloth FX properties.
Load — Loads a saved settings file. Similar to using a Preset.
Scan Motion — Scans the motion of the object and applies the scanned results (.mdd file) to the object. This means you don’t have to apply another plug to scan the motion (including bones etc).It eliminates the steps of loading the motion file back in, and also enables you to quickly scan an object’s motion to allow for the use of editFX on an object even if it’s not using dynamics.

Info — Clicking the Info button brings up a window that gives you the version # of Cloth FX and MDD file information.

EditFX Tab
- Undo — The Edit tool has its own undo. Click this button to undo the last edit that is made. You can only undo one edit.

- Edit Node — Specify the ID number of the point to be edited. If the Edit tool is activated, you can select from the Layout by clicking on the point.
- Edit Frame — There are 4 modes to edit the Node’s (point) motion path.

- Edit Start/Edit End — Use the Edit Start and Edit End Fix options to lock off frames from being edited. This is the range of frames that the user will be able to edit. All other frames will be fixed (locked).

- Edit Size — (Edit Range) This field changes the influence range.

- Sewing Tool — Enables Sewing Mode . Sewing Mode gives the user the ability to sew Nodes (points) together.

- Sewing — This button is the third step in a three-step process of sewing Nodes together using the Sewing tool.

reference materialCLOTH FX Animating Shorts by Eric Frietsch

First off you need your model which I will provide for you in this demo. For this tutorial you will be using a low polygon model of legs with shorts and a high polygon model of legs with shorts . I will explain later why you need a high-res model and a low-res model in this tutorial. Unfortunatly, ClothFX is relative the to size of model that you are using. Alot of tweaking will need to be made in order to get the best results for new characters. First off I want to give you a vocabulary of what each item is under every tab so you will have a better understanding of what to expect. *Vocab from the Lightwave 8 Manual

Basic Tab -Weight defines the weight of the material. -The Spring coefficient controls the springiness or stiffness of the material. -Viscosity controls the impact of a collision. If an object bounces, a higher Viscosity value will have less bounce motion because the bouncing force is absorbed by the Viscosity . - Resistance controls the amount of air resistance. - Sub-Structure — The surface of a pure, elastic body model has a high degree of freedom, which causes the object to easily distort. To prevent distortion, you can apply an auxiliary MD form, called a Sub-structure , to restrict the instability of the surface. This can improve your results with a twodimensional object (i.e., one with no thickness) making it act as if it has some thickness. However, this reinforcement can require a high Sub-structure setting that can take longer to calculate. - Hold-Structure — Because a pure elastic body model simulates only the surface structure, it can be limited to two-dimensional motions, like with a bed sheet. In order to simulate elastic threedimensional motions, such as some gelatin, a Hold-structure needs to be used. This parameter causes a surface to tend to maintain its original shape, like gelatin does when it jiggles.
Collision Tab - Collision Detect — reflects the influence of other objects upon the motion of an object. This lets you create complex motions caused by obstacles. The simulation is performed by taking an object that collides (the collision object) with the elastic body model (dynamic object) into the calculation. - Exclusive Collision — Selecting an item from this list will exclude all other collision objects from the calculation. - Interaction — By Default you would want Interaction set to “All” so that All geometry with interact with each other. However you have the option of limiting the interaction by Vertex Maps . - Collision Offset — By default the collision offset is set to 0 so that the collision object will collide with the surface of the target object allowing the target object to deform. Increasing the Collision Offset will result in the collision object deforming the target object at the distance specified in the collision offset field. - Bound — adds a rebounding speed change at collision. - Friction — Like real world friction, the Friction parameter makes the surface less slippery. So if you want the Dynamic object to tend to slip off the collision object, set Friction to 0. If you want it to stick more, increase the value. - Connected — If you activate “Connected” it will treat each set of Contiguous points as separate objects that collide with themselves. - Self Collision — The Self Collision setting can prevent an object from crossing itself when the object is transformed. Self Collision is calculated based on a point on the target object and a polygon on the collision object. If a surface has Self Collision and Collision Detection active, Self Collision is computed on the same surface. - Double Side — Collision Detection is detected even if the motion is from behind the polygon. Advance Tab - Resistance Mode — Resistance mode tells the Resistance setting in Basic Tab how to react. With some Resistance you can see as you change Mode settings how the polygons will resist wind effects. - None — points move based on wind direction. - Polygon — points move based on wind direction + point normal. - Polygon (front) — points facing the wind move based on wind direction + point normal. - Polygon(back) — points facing away from wind move based on wind direction + point normal. NOTE: Resistance settings only apply to wind. - Mode Ratio — sets the amount of Resistance applied to specific effects set by Resistance Mode versus standard. 75% sets 75% of the Resistance Mode and 25% of the standard resistance. - Compress Stress — controls the amount of compression a surface exhibits as a result of stress. A soft fabric like cotton can be made using a large Spring value and a low Compress Stress setting. A stiffer fabric would use a higher Compress Stress setting. - Stretch Limit — To prevent a surface from stretching like rubber, lower the Stretch-limit below the default value of 100%. This restricts the amount of the surface to be stretched. - Polygon Size — Changes the surface to a specified size. For example, a value of 90% reduces the size of the surface to 90%. Use Polygon Size to reduce the looseness of a dress or to create frills. - Fiber effect — Allows you to set an axis for the traditional Fiber effect , basically making a certain axis “stronger” than the others. For example, setting Y makes the built-in folds of the dress (dress_ fx002) stronger so the folds aren’t disregarded during calculation. - Relax Start — The Cloth FX object starts out with no Stress State Etc Tab - Gravity(m/s^2) — Specify the direction and intensity of gravity along the world axes. - Resolution — Set the accuracy of calculation by how big the maximum error is. When it approaches 0 the accuracy increases and errors will decrease, but calculation amount will also increase so it will take more time to calculate. - View Feedback — Set the feedback in Layout when controlling Cloth FX. When the display is poor or the display speed is slow, you uncheck this. - Numeric Feedback — Set the numerical feedback in Layout when controlling Cloth FX. When the display is poor or the display speed is slow, you uncheck this. - Presets — Similar to surface presets, Cloth FX has 5 built in presets that give you a good place to start. Presets include: Cotton Thin, Cotton Thick, Silk, Rubber, Jelly. File Tab - Load Motion — Loads a previously generated motion file. - Clear Motion — Clears a loaded Motion file. - Save Motion — saves the generated motion to a file, which will be used subsequently to deform the object. - Load Limit — Loads Limited Frames. Example : If you have a MDD file with 2000 frames of data you can limit it to just 100 frames to make it less processor intensive. - Playback Mode Normal — Plays back all Motion settings of the .mdd file. Local — Plays back based on the local translations (move rotate and scale) of the object. Allows an .mdd deformation on an object while respecting new motion applied to that object. Distance Map — Adjusts the motion data to the movement of object. When speed is 100%, 1s (second) animation is played back concerning the movement of 1m. Speed — When Playback Mode is set to Local or Distant the user is able to control the playback speed. Node Match — When Node Match is activated, the motion data can be played back on the object’s local position. Shift Frames — The user can shift the time the motion starts. Use Shift Frames if you need the motion to start on an earlier or later frame. Loop — The user has the option to loop the motion file in two ways. *Repeat* — Plays the motion from start to finish and then repeats the motion from start to finish continually. *Oscillate* — Plays the Motion from start to finish and then plays it from the end frame backwards to the start frame and then repeats. (Ping Pong motion) Motion Size — Motion Size increases the distance relationship between points in a motion file. Copy — Use the Copy button to copy the current settings between dynamic objects. Paste — Use the Paste button to paste the current settings between dynamic objects. Save — Saves all the settings contained in the Cloth FX properties. Load — Loads a saved settings file. Similar to using a Preset. Scan Motion — Scans the motion of the object and applies the scanned results (.mdd file) to the object. This means you don’t have to apply another plug to scan the motion (including bones etc).It eliminates the steps of loading the motion file back in, and also enables you to quickly scan an object’s motion to allow for the use of editFX on an object even if it’s not using dynamics. Info — Clicking the Info button brings up a window that gives you the version # of Cloth FX and MDD file information. EditFX Tab - Undo — The Edit tool has its own undo. Click this button to undo the last edit that is made. You can only undo one edit. - Edit Node — Specify the ID number of the point to be edited. If the Edit tool is activated, you can select from the Layout by clicking on the point. - Edit Frame — There are 4 modes to edit the Node’s (point) motion path. - Edit Start/Edit End — Use the Edit Start and Edit End Fix options to lock off frames from being edited. This is the range of frames that the user will be able to edit. All other frames will be fixed (locked). - Edit Size — (Edit Range) This field changes the influence range. - Sewing Tool — Enables Sewing Mode . Sewing Mode gives the user the ability to sew Nodes (points) together. - Sewing — This button is the third step in a three-step process of sewing Nodes together using the Sewing tool.


Step1 Load the scene named ShortsClothFX into layout. This is just a basic model that uses forward kinamatics. Scrub thru and you can see there is a very basic leg movement that we will use in order to see the effects of the legs on the cloth. Step2 Ok lets get started. Select Layer2 of the objects and click (p) for properties

You should get a screen that looks like this. In the properties panel there are many tabs, but the tab that we want is the Dynamics tab. Click on the Dynamics tab and then go to Add Dynamic. Select Cloth.

ClothFX will appear under Name and double click it. You should see more tabs pop up.

Under the Basic Tab there is a panel that says Fix. You want to select the item that says Fixed/Part. What this does is keep the shorts from falling off the screen when you calculate. In order to create fixed points you must fix them in Modler under the View tab. Then Create Part and name appropriatly.

Step3 Next go to the Etc Tab and choose Cotton(thick) under the Presets panel. Also add -9.8m Gravity under the Y axis. As this is real world gravity. Hit Calculate to see what happens.

Step4 Now we need to tell the cloth that there is a collision object that it needs to use. Select Fatty_LowRes:Layer1 Click P for Properties and go to the dynamic tab for this object as well. Add ClothFX to this object layer as well. Under the Basic tab you will need to Fix <all>. This prevents your object or our Character in this case from being deformed in any way when the Calculate button is hit.

Step5 Next you will want to go to the Collision tab and make sure the Collision Detect is set to <all>. This lets the cloth know what the collision object is. Also turn the Interaction to <all> because we want the cloth to interact with our entire model. Here are the settings that seem to work with this character. Again the peramiters entered depend apon the size and scale of your model.
Step6 Hit Calculate and you shoud see your time bar go through the frames and see the cloth work correctly agains the model. Step7 Ok now we have a low polygon calculation of our desired outcome. We need to save our calculation. I went to Save Motion and named it cloth. This allows you to not have to Calculate it out again if you close Layout and open it back up again.

Step 8 Ok now we need to get our hi-res models to replace our low- res models. The reason behind useing low polygon models in the first place is that it makes the Calculation time much faster. Depending on how many polygons your hi-res model has, it could take years to render and that is where the low-res models come in. Make sure you are selected on Fatty_LowRes:Layer1 and go and Replace this layer with Fatty_HiRes:Layer1. OOO Yeah now it is looking better.

Step9 Bringing in the hi-res model of the Shorts however is not as easy. The first thing we need to do is load in the hi-res model of the shorts labeled Fatty_HiRes:Layer2

Step 10 The next thing we need to do is Parent the hi-Res model of the shorts to the low-res model of the shorts. So his (m) for Motion Options and parent away.

Step 11 Now, while still on the hi-res shorts layer we need to hit (p) for the properties panel and go to the deform tab and Add a Displacement. The Displacement we are adding is called FX_Metalink. This niffty little plugin links all the calculations we did from the low-res model of the shorts and applies it to the hi-res model of the shorts.

Step 12 The last thing we need to do is go into the Scene Editor and hide Fatty_LowRes:Layer2 so it is not viewable. This is a fairly quick and easy method in creating great looking clothing for a character.

web page contact: Vonda Yarberry SMSU - Computer Animation Resources Home