
(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 7 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 (* ux (* (- 1.0 ux) maxCos))))
(+
(+
(*
(*
(cos (log (+ 1.0 (expm1 (* uy (* 2.0 PI))))))
(sqrt (+ 1.0 (* t_0 (* ux (* maxCos (+ ux -1.0)))))))
xi)
(* yi (sin (* PI (* uy 2.0)))))
(* t_0 zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ux * ((1.0f - ux) * maxCos);
return (((cosf(logf((1.0f + expm1f((uy * (2.0f * ((float) M_PI))))))) * sqrtf((1.0f + (t_0 * (ux * (maxCos * (ux + -1.0f))))))) * xi) + (yi * sinf((((float) M_PI) * (uy * 2.0f))))) + (t_0 * zi);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(ux * Float32(Float32(Float32(1.0) - ux) * maxCos)) return Float32(Float32(Float32(Float32(cos(log(Float32(Float32(1.0) + expm1(Float32(uy * Float32(Float32(2.0) * Float32(pi))))))) * sqrt(Float32(Float32(1.0) + Float32(t_0 * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0)))))))) * xi) + Float32(yi * sin(Float32(Float32(pi) * Float32(uy * Float32(2.0)))))) + Float32(t_0 * zi)) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := ux \cdot \left(\left(1 - ux\right) \cdot maxCos\right)\\
\left(\left(\cos \log \left(1 + \mathsf{expm1}\left(uy \cdot \left(2 \cdot \pi\right)\right)\right) \cdot \sqrt{1 + t\_0 \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)}\right) \cdot xi + yi \cdot \sin \left(\pi \cdot \left(uy \cdot 2\right)\right)\right) + t\_0 \cdot zi
\end{array}
\end{array}
Initial program 98.8%
associate-*r*98.8%
log1p-expm1-u98.8%
log1p-undefine98.8%
Applied egg-rr98.8%
Taylor expanded in ux around 0 98.8%
associate-*r*98.8%
Simplified98.8%
Final simplification98.8%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* xi (sqrt (+ 1.0 (* (* ux maxCos) (* (* ux maxCos) (+ ux -1.0)))))) (fma yi (sin (* PI (* uy 2.0))) (* (* ux maxCos) (* (- 1.0 ux) zi)))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (xi * sqrtf((1.0f + ((ux * maxCos) * ((ux * maxCos) * (ux + -1.0f)))))), fmaf(yi, sinf((((float) M_PI) * (uy * 2.0f))), ((ux * maxCos) * ((1.0f - ux) * zi))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(xi * sqrt(Float32(Float32(1.0) + Float32(Float32(ux * maxCos) * Float32(Float32(ux * maxCos) * Float32(ux + Float32(-1.0))))))), fma(yi, sin(Float32(Float32(pi) * Float32(uy * Float32(2.0)))), Float32(Float32(ux * maxCos) * Float32(Float32(Float32(1.0) - ux) * zi)))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), xi \cdot \sqrt{1 + \left(ux \cdot maxCos\right) \cdot \left(\left(ux \cdot maxCos\right) \cdot \left(ux + -1\right)\right)}, \mathsf{fma}\left(yi, \sin \left(\pi \cdot \left(uy \cdot 2\right)\right), \left(ux \cdot maxCos\right) \cdot \left(\left(1 - ux\right) \cdot zi\right)\right)\right)
\end{array}
Initial program 98.8%
associate-+l+98.9%
associate-*l*98.9%
fma-define98.9%
Simplified98.8%
Taylor expanded in maxCos around 0 98.9%
+-commutative98.9%
fma-define98.9%
associate-*r*98.9%
*-commutative98.9%
*-commutative98.9%
*-commutative98.9%
associate-*r*98.8%
*-commutative98.8%
*-commutative98.8%
*-commutative98.8%
*-commutative98.8%
Simplified98.8%
Taylor expanded in ux around 0 98.8%
Final simplification98.8%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* PI (* uy 2.0))) (t_1 (* ux (* (- 1.0 ux) maxCos))))
(+
(* t_1 zi)
(+
(* yi (sin t_0))
(*
xi
(* (sqrt (+ 1.0 (* t_1 (* ux (* maxCos (+ ux -1.0)))))) (cos t_0)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ((float) M_PI) * (uy * 2.0f);
float t_1 = ux * ((1.0f - ux) * maxCos);
return (t_1 * zi) + ((yi * sinf(t_0)) + (xi * (sqrtf((1.0f + (t_1 * (ux * (maxCos * (ux + -1.0f)))))) * cosf(t_0))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(pi) * Float32(uy * Float32(2.0))) t_1 = Float32(ux * Float32(Float32(Float32(1.0) - ux) * maxCos)) return Float32(Float32(t_1 * zi) + Float32(Float32(yi * sin(t_0)) + Float32(xi * Float32(sqrt(Float32(Float32(1.0) + Float32(t_1 * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0))))))) * cos(t_0))))) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = single(pi) * (uy * single(2.0)); t_1 = ux * ((single(1.0) - ux) * maxCos); tmp = (t_1 * zi) + ((yi * sin(t_0)) + (xi * (sqrt((single(1.0) + (t_1 * (ux * (maxCos * (ux + single(-1.0))))))) * cos(t_0)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \pi \cdot \left(uy \cdot 2\right)\\
t_1 := ux \cdot \left(\left(1 - ux\right) \cdot maxCos\right)\\
t\_1 \cdot zi + \left(yi \cdot \sin t\_0 + xi \cdot \left(\sqrt{1 + t\_1 \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)} \cdot \cos t\_0\right)\right)
\end{array}
\end{array}
Initial program 98.8%
Taylor expanded in ux around 0 98.8%
associate-*r*98.8%
Simplified98.8%
Final simplification98.8%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (- 1.0 ux) (* ux maxCos))))
(fma
(cos (* uy (* 2.0 PI)))
(* xi (sqrt (- 1.0 (* t_0 t_0))))
(- (* 2.0 (* uy (* PI yi))) (* maxCos (* ux (* zi (+ ux -1.0))))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * (ux * maxCos);
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (xi * sqrtf((1.0f - (t_0 * t_0)))), ((2.0f * (uy * (((float) M_PI) * yi))) - (maxCos * (ux * (zi * (ux + -1.0f))))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * Float32(ux * maxCos)) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(xi * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0)))), Float32(Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * yi))) - Float32(maxCos * Float32(ux * Float32(zi * Float32(ux + Float32(-1.0))))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot \left(ux \cdot maxCos\right)\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), xi \cdot \sqrt{1 - t\_0 \cdot t\_0}, 2 \cdot \left(uy \cdot \left(\pi \cdot yi\right)\right) - maxCos \cdot \left(ux \cdot \left(zi \cdot \left(ux + -1\right)\right)\right)\right)
\end{array}
\end{array}
Initial program 98.8%
associate-+l+98.9%
associate-*l*98.9%
fma-define98.9%
Simplified98.8%
Taylor expanded in maxCos around 0 98.9%
+-commutative98.9%
fma-define98.9%
associate-*r*98.9%
*-commutative98.9%
*-commutative98.9%
*-commutative98.9%
associate-*r*98.8%
*-commutative98.8%
*-commutative98.8%
*-commutative98.8%
*-commutative98.8%
Simplified98.8%
Taylor expanded in uy around 0 90.1%
Final simplification90.1%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (- 1.0 ux) (* ux maxCos))))
(fma
(cos (* uy (* 2.0 PI)))
(* xi (sqrt (- 1.0 (* t_0 t_0))))
(+ (* maxCos (* ux zi)) (* uy (* 2.0 (* PI yi)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * (ux * maxCos);
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (xi * sqrtf((1.0f - (t_0 * t_0)))), ((maxCos * (ux * zi)) + (uy * (2.0f * (((float) M_PI) * yi)))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * Float32(ux * maxCos)) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(xi * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0)))), Float32(Float32(maxCos * Float32(ux * zi)) + Float32(uy * Float32(Float32(2.0) * Float32(Float32(pi) * yi))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot \left(ux \cdot maxCos\right)\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), xi \cdot \sqrt{1 - t\_0 \cdot t\_0}, maxCos \cdot \left(ux \cdot zi\right) + uy \cdot \left(2 \cdot \left(\pi \cdot yi\right)\right)\right)
\end{array}
\end{array}
Initial program 98.8%
associate-+l+98.9%
associate-*l*98.9%
fma-define98.9%
Simplified98.8%
Taylor expanded in ux around 0 96.2%
Taylor expanded in uy around 0 87.8%
*-commutative87.8%
associate-*l*87.8%
*-commutative87.8%
Simplified87.8%
Final simplification87.8%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* xi (sqrt (- 1.0 (* (* ux maxCos) (* ux maxCos))))) (* maxCos (* ux (* (- 1.0 ux) zi)))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (xi * sqrtf((1.0f - ((ux * maxCos) * (ux * maxCos))))), (maxCos * (ux * ((1.0f - ux) * zi))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(xi * sqrt(Float32(Float32(1.0) - Float32(Float32(ux * maxCos) * Float32(ux * maxCos))))), Float32(maxCos * Float32(ux * Float32(Float32(Float32(1.0) - ux) * zi)))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), xi \cdot \sqrt{1 - \left(ux \cdot maxCos\right) \cdot \left(ux \cdot maxCos\right)}, maxCos \cdot \left(ux \cdot \left(\left(1 - ux\right) \cdot zi\right)\right)\right)
\end{array}
Initial program 98.8%
associate-+l+98.9%
associate-*l*98.9%
fma-define98.9%
Simplified98.8%
Taylor expanded in uy around 0 59.4%
*-commutative59.4%
Simplified59.4%
Taylor expanded in ux around 0 59.4%
Taylor expanded in ux around 0 59.4%
Final simplification59.4%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* xi (sqrt (- 1.0 (* (* ux maxCos) (* ux maxCos))))) (* maxCos (* ux zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (xi * sqrtf((1.0f - ((ux * maxCos) * (ux * maxCos))))), (maxCos * (ux * zi)));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(xi * sqrt(Float32(Float32(1.0) - Float32(Float32(ux * maxCos) * Float32(ux * maxCos))))), Float32(maxCos * Float32(ux * zi))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), xi \cdot \sqrt{1 - \left(ux \cdot maxCos\right) \cdot \left(ux \cdot maxCos\right)}, maxCos \cdot \left(ux \cdot zi\right)\right)
\end{array}
Initial program 98.8%
associate-+l+98.9%
associate-*l*98.9%
fma-define98.9%
Simplified98.8%
Taylor expanded in uy around 0 59.4%
*-commutative59.4%
Simplified59.4%
Taylor expanded in ux around 0 59.4%
Taylor expanded in ux around 0 59.4%
Taylor expanded in ux around 0 57.3%
Final simplification57.3%
herbie shell --seed 2024043
(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)))