public void changeSpeed(LayeredZigzag blob, float secondsSinceLastCall) {
for (MovLine ld : blob.allLineDatas()) {
if (ld.springTightness == 0) {
// This is an optimization, not a behavior change, because force is multiplied by
// springTightness
continue;
}
MovCorner a = ld.adjacentCorners.get(0), b = ld.adjacentCorners.get(1);
float dy = b.y - a.y;
float dx = b.x - a.x;
float distance = (float) Math.sqrt(dx * dx + dy * dy);
if (distance == 0) continue;
float wantToAddToDistance = ld.targetDistance - distance; // positive or negative
// wantToAddToDistance =
// (float)(2*MathUtil.sigmoid(5*wantToAddToDistance/ld.targetDistance)-1)*ld.targetDistance;
wantToAddToDistance =
(float)
(2 * MathUtil.sigmoid(multParamOfSigmoid * wantToAddToDistance / ld.targetDistance)
- 1);
float normDy = dy / distance, normDx = dx / distance;
float addToEachMomentum =
secondsSinceLastCall * wantToAddToDistance * mult * ld.springTightness;
float addToMomentumY = normDy * addToEachMomentum;
float addToMomentumX = normDx * addToEachMomentum;
b.addToSpeedY += addToMomentumY / b.mass;
a.addToSpeedY -= addToMomentumY / a.mass;
b.addToSpeedX += addToMomentumX / b.mass;
a.addToSpeedX -= addToMomentumX / a.mass;
}
}
