draping dforce objects

alisa53

I'm just wondering about dforce "tricks of the trade."  Currently I'm working on a render where a female is lying on a platform.  I need the dress to drape over the platform.  But if I keep the platform in the simulation, there is a lot of "drag" as it simulates, eventually causing the exploding polygon phenomenon.  So how do you accomplish that kind of drape?  The more objects that contact the dforce item, the more likely you'll get a failure...

Elliandra

Hi there!
First off if you don't have it I would serioulsy recommend getting the dForce Master for Cloth from EcVh0. It's one I use all the time when working with dForce and it even has a "Fix Explosion" preset lol

For the actual simulation it's easier to drape using an animated timeline than to go from memorized in the single frame option. For longer dresses I usually do around 90 frames and start with the base G8F at the zero frame in default pose then while still at the Zero Frame I move her to the approximate location of where I want the final pose, then you move her forward and up off the floor and hit the keyframe button. this will allow the cloth to flow nicely during sim and you can even have her offset to one side or the other if you want the fabric to drape that way!

Important Notes: 
1. Make sure you do any camera movements while adjusting things in your scene using the Perspective camera and NOT your main camera if you already have it set up!!!
2. In the Scene Tab click on the main camera you want to render through for your scene and then in Parameters click the menu and "Memorize/Memorize Selected Item" this way if you accidently move the camera you can just right click and reset it and it will go into the correct place.
3. If you have moved something out of the default location like the platform you are using you can also memorize it like you did the camera above.
4. If you are working with multi-layered outfits you will want to simulate each piece seperately if you are having issues. Simulate from the item closest to the skin and work your way outwards.
5. If you have super long dresses and are getting the feet/toes poking through the hemline you can just point the feet down and that will take care of it usually.

Making your Animation:
1. Open your timeline and make sure it's on Frame 0 and that G8F is set to default shape etc. (you'll see why in a minute) set your total frames on the bottom left to 91 as we'll be using a 90 frame animation for this.
2. Using her main body transform dials move her to the location you need her in your scene and then move her slightly to the front or back and then to the left or right depending on how you want the fabric to drape in the scene. Lift her up on Y-Trans so the clothing can fall properly and will help with strange folding/essplossions. Now with her selected in the Parameters Tab go to "Memorize/Selected Figure" this way if you need to adjust her location later you can just hit restore figure pose (Later on if you need to adjust the "Base Location" you can always readjust her and then re-memorize the figure.). Now hit the Add Keyframe Button. 
3. Move ahead to frame 20 (If I'm using less than a 90 frame animation I go to 10 instead). This is where you will apply your character shapes/morphs. The reason to wait until now to apply them in the simulation is so that the fabric drapes naturally over the morphed shape since it will be draping as the shape is changing. Like when you have a large chested character and the clothing doesn't have support morphs for her your clothing will start off all crumpled and may retain the crumpling during simulation sometimes. So applying the morphs later in the timeline saves you this hassle!  Make sure she is still in the original pose you put her in for Frame Zero!! Hit your Add Keyframe button
4. Ok now move the animation to around Frame 55 and apply the pose you want to use and hit your Add keyframe button.
5. In the Simulation Settings Pane turn off Start Bones from Memorized Pose and set the Frames to Simulate to Animated (Use Timeline Play Range)
6. Save your scene!!!
7. Now you can run your simulation!

cajhin

A few simpler tips to add to Elliandra's advanced workflow...
(btw. 3. is interesting, apply the morphs during the timeline, I'll try that one out)

Always keep in mind the dForce rule: simulated cloth must not cut into other objects as the cloth moves around. It panics/explodes when
a) the cloth already sticks into something at the start of the simulation
b) at any point during the simulation, the cloth gets stuck between figure and ground, where the figure sticks into the ground (or a hand sticks into the leg)

In both cases, dForce doesn't know how to *not* intersect the cloth with the objects.
To check that the figure does not cut into the ground, but floats at least a mm above it, view the ground from below.

With a timeline, it's easier to control the movement of the figure. It's less simple though.

I've had some success with not animating the figure, but instead moving the floor down at frame 0 and then move it up to its final position. The cloth moves less that way.

For quick action I like to simulate from memorized pose. From standing to lying down is a lot of movement though, sometimes results are better when I start from a crouching position. Just make sure the cloth does not intersect with anything in the memorized pose.

 

alisa53

Elliandra said:

Hi there!
First off if you don't have it I would serioulsy recommend getting the dForce Master for Cloth from EcVh0. It's one I use all the time when working with dForce and it even has a "Fix Explosion" preset lol

For the actual simulation it's easier to drape using an animated timeline than to go from memorized in the single frame option. For longer dresses I usually do around 90 frames and start with the base G8F at the zero frame in default pose then while still at the Zero Frame I move her to the approximate location of where I want the final pose, then you move her forward and up off the floor and hit the keyframe button. this will allow the cloth to flow nicely during sim and you can even have her offset to one side or the other if you want the fabric to drape that way!

Important Notes: 
1. Make sure you do any camera movements while adjusting things in your scene using the Perspective camera and NOT your main camera if you already have it set up!!!
2. In the Scene Tab click on the main camera you want to render through for your scene and then in Parameters click the menu and "Memorize/Memorize Selected Item" this way if you accidently move the camera you can just right click and reset it and it will go into the correct place.
3. If you have moved something out of the default location like the platform you are using you can also memorize it like you did the camera above.
4. If you are working with multi-layered outfits you will want to simulate each piece seperately if you are having issues. Simulate from the item closest to the skin and work your way outwards.
5. If you have super long dresses and are getting the feet/toes poking through the hemline you can just point the feet down and that will take care of it usually.

Making your Animation:
1. Open your timeline and make sure it's on Frame 0 and that G8F is set to default shape etc. (you'll see why in a minute) set your total frames on the bottom left to 91 as we'll be using a 90 frame animation for this.
2. Using her main body transform dials move her to the location you need her in your scene and then move her slightly to the front or back and then to the left or right depending on how you want the fabric to drape in the scene. Lift her up on Y-Trans so the clothing can fall properly and will help with strange folding/essplossions. Now with her selected in the Parameters Tab go to "Memorize/Selected Figure" this way if you need to adjust her location later you can just hit restore figure pose (Later on if you need to adjust the "Base Location" you can always readjust her and then re-memorize the figure.). Now hit the Add Keyframe Button. 
3. Move ahead to frame 20 (If I'm using less than a 90 frame animation I go to 10 instead). This is where you will apply your character shapes/morphs. The reason to wait until now to apply them in the simulation is so that the fabric drapes naturally over the morphed shape since it will be draping as the shape is changing. Like when you have a large chested character and the clothing doesn't have support morphs for her your clothing will start off all crumpled and may retain the crumpling during simulation sometimes. So applying the morphs later in the timeline saves you this hassle!  Make sure she is still in the original pose you put her in for Frame Zero!! Hit your Add Keyframe button
4. Ok now move the animation to around Frame 55 and apply the pose you want to use and hit your Add keyframe button.
5. In the Simulation Settings Pane turn off Start Bones from Memorized Pose and set the Frames to Simulate to Animated (Use Timeline Play Range)
6. Save your scene!!!
7. Now you can run your simulation!

Thanks for the very detailed response.  I'll try playing around with it.

alisa53

cajhin said:

A few simpler tips to add to Elliandra's advanced workflow...
(btw. 3. is interesting, apply the morphs during the timeline, I'll try that one out)

Always keep in mind the dForce rule: simulated cloth must not cut into other objects as the cloth moves around. It panics/explodes when
a) the cloth already sticks into something at the start of the simulation
b) at any point during the simulation, the cloth gets stuck between figure and ground, where the figure sticks into the ground (or a hand sticks into the leg)

In both cases, dForce doesn't know how to *not* intersect the cloth with the objects.
To check that the figure does not cut into the ground, but floats at least a mm above it, view the ground from below.

With a timeline, it's easier to control the movement of the figure. It's less simple though.

I've had some success with not animating the figure, but instead moving the floor down at frame 0 and then move it up to its final position. The cloth moves less that way.

For quick action I like to simulate from memorized pose. From standing to lying down is a lot of movement though, sometimes results are better when I start from a crouching position. Just make sure the cloth does not intersect with anything in the memorized pose.

 

Thanks for your tips.  I'll give these ideas a try.