i watched a lot of DVD's about dynamic clothing. WETA and ILM and every studio doing CGI are using dynamic clothing.  the clothing and human body is very detailed. they say that they dont use the final body(render) as collision. because the mesh is to detailed. and it true. you dont need every vein as a collision for clothes.

 

so here i made a very low poly M4 collision body. its meant to be used for dynamic clothing. so  set collide against  .  i think more then  70% times you can use this. but there are times when you should use M4 for collision. if your clothing is very dense and has a lot of details. if you want small foldes its maybe good to use M4 since the low body figure is not smooth enough.

-the figure is conforming. so conform to M4. that way you only pose M4

-before you render turn the low body invisible.

 

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