\[\left(\left(\left(\left(\left(\left(\left(ar \cdot ar - br \cdot br\right) + \left(\left(\left(tr \cdot \left(br - ar\right) + tg \cdot \left(bg - ag\right)\right) + tb \cdot \left(bb - ab\right)\right) + ta \cdot \left(ba - aa\right)\right) \cdot 2\right) + ag \cdot ag\right) - bg \cdot bg\right) + ab \cdot ab\right) - bb \cdot bb\right) + aa \cdot aa\right) - ba \cdot ba\]

\left(\left(\left(\left(\left(\left(\left(ar \cdot ar - br \cdot br\right) + \left(\left(\left(tr \cdot \left(br - ar\right) + tg \cdot \left(bg - ag\right)\right) + tb \cdot \left(bb - ab\right)\right) + ta \cdot \left(ba - aa\right)\right) \cdot 2\right) + ag \cdot ag\right) - bg \cdot bg\right) + ab \cdot ab\right) - bb \cdot bb\right) + aa \cdot aa\right) - ba \cdot ba

double code(double ar, double br, double tr, double tg, double bg, double ag, double tb, double bb, double ab, double ta, double ba, double aa) {
	return ((double) (((double) (((double) (((double) (((double) (((double) (((double) (((double) (((double) (ar * ar)) - ((double) (br * br)))) + ((double) (((double) (((double) (((double) (((double) (tr * ((double) (br - ar)))) + ((double) (tg * ((double) (bg - ag)))))) + ((double) (tb * ((double) (bb - ab)))))) + ((double) (ta * ((double) (ba - aa)))))) * 2.0)))) + ((double) (ag * ag)))) - ((double) (bg * bg)))) + ((double) (ab * ab)))) - ((double) (bb * bb)))) + ((double) (aa * aa)))) - ((double) (ba * ba))));
}

Reproduce

herbie shell --seed 2020153 
(FPCore (ar br tr tg bg ag tb bb ab ta ba aa)
  :name "(- (+ (- (+ (- (+ (+ (- (* ar ar) (* br br)) (* (+ (+ (+ (* tr (- br ar)) (* tg (- bg ag))) (* tb (- bb ab))) (* ta (- ba aa))) 2)) (* ag ag)) (* bg bg)) (* ab ab)) (* bb bb)) (* aa aa)) (* ba ba))"
  :precision binary64
  (- (+ (- (+ (- (+ (+ (- (* ar ar) (* br br)) (* (+ (+ (+ (* tr (- br ar)) (* tg (- bg ag))) (* tb (- bb ab))) (* ta (- ba aa))) 2.0)) (* ag ag)) (* bg bg)) (* ab ab)) (* bb bb)) (* aa aa)) (* ba ba)))

Cannot sample enough valid points. (more)

Reproduce