the garment fabric you saw i don't think you can make at home. i've seen it on the bolt in new york (very pricey) and i've seen it on finished clothing (not so pricey). my daughter has a blouse out of that stuff and it's very washable. i think it's poly and permanently randomly pressed, as said above. the kind i'm talking about has no elastic. it's very thin.
texture magic doesn't stretch when it's done and finishes much thicker.