
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (* (- 1.0 ux) maxCos) ux))
(t_1 (sqrt (- 1.0 (* t_0 t_0))))
(t_2 (* (* uy 2.0) PI)))
(+ (+ (* (* (cos t_2) t_1) xi) (* (* (sin t_2) t_1) yi)) (* t_0 zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ((1.0f - ux) * maxCos) * ux;
float t_1 = sqrtf((1.0f - (t_0 * t_0)));
float t_2 = (uy * 2.0f) * ((float) M_PI);
return (((cosf(t_2) * t_1) * xi) + ((sinf(t_2) * t_1) * yi)) + (t_0 * zi);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(Float32(1.0) - ux) * maxCos) * ux) t_1 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) t_2 = Float32(Float32(uy * Float32(2.0)) * Float32(pi)) return Float32(Float32(Float32(Float32(cos(t_2) * t_1) * xi) + Float32(Float32(sin(t_2) * t_1) * yi)) + Float32(t_0 * zi)) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ((single(1.0) - ux) * maxCos) * ux; t_1 = sqrt((single(1.0) - (t_0 * t_0))); t_2 = (uy * single(2.0)) * single(pi); tmp = (((cos(t_2) * t_1) * xi) + ((sin(t_2) * t_1) * yi)) + (t_0 * zi); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(\left(1 - ux\right) \cdot maxCos\right) \cdot ux\\
t_1 := \sqrt{1 - t_0 \cdot t_0}\\
t_2 := \left(uy \cdot 2\right) \cdot \pi\\
\left(\left(\cos t_2 \cdot t_1\right) \cdot xi + \left(\sin t_2 \cdot t_1\right) \cdot yi\right) + t_0 \cdot zi
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (* (- 1.0 ux) maxCos) ux))
(t_1 (sqrt (- 1.0 (* t_0 t_0))))
(t_2 (* (* uy 2.0) PI)))
(+ (+ (* (* (cos t_2) t_1) xi) (* (* (sin t_2) t_1) yi)) (* t_0 zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ((1.0f - ux) * maxCos) * ux;
float t_1 = sqrtf((1.0f - (t_0 * t_0)));
float t_2 = (uy * 2.0f) * ((float) M_PI);
return (((cosf(t_2) * t_1) * xi) + ((sinf(t_2) * t_1) * yi)) + (t_0 * zi);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(Float32(1.0) - ux) * maxCos) * ux) t_1 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) t_2 = Float32(Float32(uy * Float32(2.0)) * Float32(pi)) return Float32(Float32(Float32(Float32(cos(t_2) * t_1) * xi) + Float32(Float32(sin(t_2) * t_1) * yi)) + Float32(t_0 * zi)) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ((single(1.0) - ux) * maxCos) * ux; t_1 = sqrt((single(1.0) - (t_0 * t_0))); t_2 = (uy * single(2.0)) * single(pi); tmp = (((cos(t_2) * t_1) * xi) + ((sin(t_2) * t_1) * yi)) + (t_0 * zi); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(\left(1 - ux\right) \cdot maxCos\right) \cdot ux\\
t_1 := \sqrt{1 - t_0 \cdot t_0}\\
t_2 := \left(uy \cdot 2\right) \cdot \pi\\
\left(\left(\cos t_2 \cdot t_1\right) \cdot xi + \left(\sin t_2 \cdot t_1\right) \cdot yi\right) + t_0 \cdot zi
\end{array}
\end{array}
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* uy (* 2.0 PI))))
(fma
(* (- 1.0 ux) maxCos)
(* ux zi)
(*
(sqrt
(+ 1.0 (* maxCos (* (- 1.0 ux) (* (* ux ux) (* maxCos (+ ux -1.0)))))))
(+ (* (cos t_0) xi) (* (sin t_0) yi))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = uy * (2.0f * ((float) M_PI));
return fmaf(((1.0f - ux) * maxCos), (ux * zi), (sqrtf((1.0f + (maxCos * ((1.0f - ux) * ((ux * ux) * (maxCos * (ux + -1.0f))))))) * ((cosf(t_0) * xi) + (sinf(t_0) * yi))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(uy * Float32(Float32(2.0) * Float32(pi))) return fma(Float32(Float32(Float32(1.0) - ux) * maxCos), Float32(ux * zi), Float32(sqrt(Float32(Float32(1.0) + Float32(maxCos * Float32(Float32(Float32(1.0) - ux) * Float32(Float32(ux * ux) * Float32(maxCos * Float32(ux + Float32(-1.0)))))))) * Float32(Float32(cos(t_0) * xi) + Float32(sin(t_0) * yi)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := uy \cdot \left(2 \cdot \pi\right)\\
\mathsf{fma}\left(\left(1 - ux\right) \cdot maxCos, ux \cdot zi, \sqrt{1 + maxCos \cdot \left(\left(1 - ux\right) \cdot \left(\left(ux \cdot ux\right) \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)\right)} \cdot \left(\cos t_0 \cdot xi + \sin t_0 \cdot yi\right)\right)
\end{array}
\end{array}
Initial program 99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* ux (* maxCos (+ ux -1.0)))) (t_1 (* PI (* uy 2.0))))
(+
(+ (* xi (* (cos t_1) (sqrt (- 1.0 (* t_0 t_0))))) (* yi (sin t_1)))
(* zi (* ux (* (- 1.0 ux) maxCos))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ux * (maxCos * (ux + -1.0f));
float t_1 = ((float) M_PI) * (uy * 2.0f);
return ((xi * (cosf(t_1) * sqrtf((1.0f - (t_0 * t_0))))) + (yi * sinf(t_1))) + (zi * (ux * ((1.0f - ux) * maxCos)));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0)))) t_1 = Float32(Float32(pi) * Float32(uy * Float32(2.0))) return Float32(Float32(Float32(xi * Float32(cos(t_1) * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))))) + Float32(yi * sin(t_1))) + Float32(zi * Float32(ux * Float32(Float32(Float32(1.0) - ux) * maxCos)))) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ux * (maxCos * (ux + single(-1.0))); t_1 = single(pi) * (uy * single(2.0)); tmp = ((xi * (cos(t_1) * sqrt((single(1.0) - (t_0 * t_0))))) + (yi * sin(t_1))) + (zi * (ux * ((single(1.0) - ux) * maxCos))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\\
t_1 := \pi \cdot \left(uy \cdot 2\right)\\
\left(xi \cdot \left(\cos t_1 \cdot \sqrt{1 - t_0 \cdot t_0}\right) + yi \cdot \sin t_1\right) + zi \cdot \left(ux \cdot \left(\left(1 - ux\right) \cdot maxCos\right)\right)
\end{array}
\end{array}
Initial program 99.0%
Taylor expanded in ux around 0 98.9%
associate-*r*98.9%
*-commutative98.9%
*-commutative98.9%
*-commutative98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(fma
(* (- 1.0 ux) maxCos)
(* ux zi)
(*
(sqrt
(+ 1.0 (* maxCos (* (- 1.0 ux) (* (* ux ux) (* maxCos (+ ux -1.0)))))))
(+ (* (cos (* uy (* 2.0 PI))) xi) (* 2.0 (* yi (* uy PI)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(((1.0f - ux) * maxCos), (ux * zi), (sqrtf((1.0f + (maxCos * ((1.0f - ux) * ((ux * ux) * (maxCos * (ux + -1.0f))))))) * ((cosf((uy * (2.0f * ((float) M_PI)))) * xi) + (2.0f * (yi * (uy * ((float) M_PI)))))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(Float32(Float32(Float32(1.0) - ux) * maxCos), Float32(ux * zi), Float32(sqrt(Float32(Float32(1.0) + Float32(maxCos * Float32(Float32(Float32(1.0) - ux) * Float32(Float32(ux * ux) * Float32(maxCos * Float32(ux + Float32(-1.0)))))))) * Float32(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * xi) + Float32(Float32(2.0) * Float32(yi * Float32(uy * Float32(pi))))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\left(1 - ux\right) \cdot maxCos, ux \cdot zi, \sqrt{1 + maxCos \cdot \left(\left(1 - ux\right) \cdot \left(\left(ux \cdot ux\right) \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)\right)} \cdot \left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot xi + 2 \cdot \left(yi \cdot \left(uy \cdot \pi\right)\right)\right)\right)
\end{array}
Initial program 99.0%
Simplified99.0%
Taylor expanded in uy around 0 91.9%
associate-*r*91.9%
*-commutative91.9%
*-commutative91.9%
*-commutative91.9%
*-commutative91.9%
Simplified91.9%
expm1-log1p-u91.4%
Applied egg-rr91.4%
Taylor expanded in yi around 0 91.9%
*-commutative91.9%
associate-*r*91.9%
Simplified91.9%
Final simplification91.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(fma
(* (- 1.0 ux) maxCos)
(* ux zi)
(*
(sqrt
(+ 1.0 (* maxCos (* (- 1.0 ux) (* (* ux ux) (* maxCos (+ ux -1.0)))))))
(+ (* (cos (* uy (* 2.0 PI))) xi) (* (* uy 2.0) (* PI yi))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(((1.0f - ux) * maxCos), (ux * zi), (sqrtf((1.0f + (maxCos * ((1.0f - ux) * ((ux * ux) * (maxCos * (ux + -1.0f))))))) * ((cosf((uy * (2.0f * ((float) M_PI)))) * xi) + ((uy * 2.0f) * (((float) M_PI) * yi)))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(Float32(Float32(Float32(1.0) - ux) * maxCos), Float32(ux * zi), Float32(sqrt(Float32(Float32(1.0) + Float32(maxCos * Float32(Float32(Float32(1.0) - ux) * Float32(Float32(ux * ux) * Float32(maxCos * Float32(ux + Float32(-1.0)))))))) * Float32(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * xi) + Float32(Float32(uy * Float32(2.0)) * Float32(Float32(pi) * yi))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\left(1 - ux\right) \cdot maxCos, ux \cdot zi, \sqrt{1 + maxCos \cdot \left(\left(1 - ux\right) \cdot \left(\left(ux \cdot ux\right) \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)\right)} \cdot \left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot xi + \left(uy \cdot 2\right) \cdot \left(\pi \cdot yi\right)\right)\right)
\end{array}
Initial program 99.0%
Simplified99.0%
Taylor expanded in uy around 0 91.9%
associate-*r*91.9%
*-commutative91.9%
*-commutative91.9%
*-commutative91.9%
*-commutative91.9%
Simplified91.9%
Final simplification91.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(+
(* zi (* ux (* (- 1.0 ux) maxCos)))
(+
(*
xi
(*
(cos (* PI (* uy 2.0)))
(sqrt (+ 1.0 (* (* ux maxCos) (* ux (* maxCos (+ ux -1.0))))))))
(* 2.0 (* uy (* PI yi))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return (zi * (ux * ((1.0f - ux) * maxCos))) + ((xi * (cosf((((float) M_PI) * (uy * 2.0f))) * sqrtf((1.0f + ((ux * maxCos) * (ux * (maxCos * (ux + -1.0f)))))))) + (2.0f * (uy * (((float) M_PI) * yi))));
}
function code(xi, yi, zi, ux, uy, maxCos) return Float32(Float32(zi * Float32(ux * Float32(Float32(Float32(1.0) - ux) * maxCos))) + Float32(Float32(xi * Float32(cos(Float32(Float32(pi) * Float32(uy * Float32(2.0)))) * sqrt(Float32(Float32(1.0) + Float32(Float32(ux * maxCos) * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0))))))))) + Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * yi))))) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) tmp = (zi * (ux * ((single(1.0) - ux) * maxCos))) + ((xi * (cos((single(pi) * (uy * single(2.0)))) * sqrt((single(1.0) + ((ux * maxCos) * (ux * (maxCos * (ux + single(-1.0))))))))) + (single(2.0) * (uy * (single(pi) * yi)))); end
\begin{array}{l}
\\
zi \cdot \left(ux \cdot \left(\left(1 - ux\right) \cdot maxCos\right)\right) + \left(xi \cdot \left(\cos \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{1 + \left(ux \cdot maxCos\right) \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)}\right) + 2 \cdot \left(uy \cdot \left(\pi \cdot yi\right)\right)\right)
\end{array}
Initial program 99.0%
Taylor expanded in ux around 0 98.9%
associate-*r*98.9%
*-commutative98.9%
*-commutative98.9%
*-commutative98.9%
Simplified98.9%
Taylor expanded in uy around 0 91.8%
Taylor expanded in ux around 0 91.8%
Final simplification91.8%
herbie shell --seed 2024018
(FPCore (xi yi zi ux uy maxCos)
:name "UniformSampleCone 2"
:precision binary32
:pre (and (and (and (and (and (and (<= -10000.0 xi) (<= xi 10000.0)) (and (<= -10000.0 yi) (<= yi 10000.0))) (and (<= -10000.0 zi) (<= zi 10000.0))) (and (<= 2.328306437e-10 ux) (<= ux 1.0))) (and (<= 2.328306437e-10 uy) (<= uy 1.0))) (and (<= 0.0 maxCos) (<= maxCos 1.0)))
(+ (+ (* (* (cos (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (* (* (- 1.0 ux) maxCos) ux) (* (* (- 1.0 ux) maxCos) ux))))) xi) (* (* (sin (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (* (* (- 1.0 ux) maxCos) ux) (* (* (- 1.0 ux) maxCos) ux))))) yi)) (* (* (* (- 1.0 ux) maxCos) ux) zi)))