Fold physics (tension points, compression points, gravity acting on cloth)
Understanding how cloth hangs and bunches by tracking tension, compression, and gravity so your folds look physically convincing.
What it is
Fold physics means treating cloth as a physical object, not a pattern. You track where the fabric is pulled (tension points), where it has nowhere to go (compression points), and how gravity drags the rest downward. Folds are the visible result of those forces.
First locate what is pulling on the fabric: shoulders holding up a coat, a hand gripping a sleeve, a knee pushing against pants, a waistband stopping gravity. Those are your tension points. Folds radiate from each one, usually straight or gently curved, toward or away from the pull.
Compression points are where extra cloth bunches because it can't pass through something: the inside of a bent elbow, the back of a knee, a skirt's waistband, where a belt cinches a shirt. Folds stack, overlap, and change direction there because the fabric is pushed shorter than its relaxed length.
Gravity is the default. Anything not held up or blocked hangs toward the ground. Long garments form hanging folds from the highest support line: waist for a skirt, shoulders for a dress, rod for a curtain. When the figure moves, check where gravity wins and where a pull or collision interrupts the hang.
In practice, start from the nude figure, mark the anchor points and supports of the clothing, then build folds as a network of force lines instead of copying random squiggles. Change the pose, and the tension and compression points shift, so the folds update logically.
Why it matters
Without a sense of tension, compression, and gravity, folds float, point randomly, or cling to the body like rubber. Pants wrinkle in empty air but stay smooth at the knees; skirts flare evenly instead of hanging with weight; sleeves ignore the bend of the arm. Viewers may not name what's wrong, but they read the clothing as fake or stiff. Once the physics is clear, you can simplify or exaggerate folds and they still feel believable, because every line answers to a force you can name.
You can check it when
- ✓You can name the anchor or obstacle (hand, shoulder, belt, knee, ground) creating every main fold in your drawing.
- ✓Your folds aim toward or away from real tension points instead of spraying randomly or sitting evenly spaced with no source.
- ✓When a joint bends or the pose changes, you revise which areas are in tension or compressed, and your folds shift location and density accordingly.
- ✓Your hanging cloth (skirts, coats, capes) shows a clear top support line, then falls with gravity, breaking only where something interrupts it.