
(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 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (fma yi (sin (* PI (* uy 2.0))) (* (* 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)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), fmaf(yi, sinf((((float) M_PI) * (uy * 2.0f))), ((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(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), fma(yi, sin(Float32(Float32(pi) * Float32(uy * Float32(2.0)))), Float32(Float32(maxCos * 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), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, \mathsf{fma}\left(yi, \sin \left(\pi \cdot \left(uy \cdot 2\right)\right), \left(maxCos \cdot ux\right) \cdot \left(\left(1 - ux\right) \cdot zi\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in maxCos around 0 99.1%
+-commutative99.1%
fma-define99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
Simplified99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in ux around 0 99.1%
Final simplification99.1%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* uy (* 2.0 PI))))
(fma
(cos t_0)
(* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi)
(+ (* yi (sin t_0)) (* (- 1.0 ux) (* (* maxCos ux) zi))))))
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(cosf(t_0), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), ((yi * sinf(t_0)) + ((1.0f - ux) * ((maxCos * ux) * zi))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(uy * Float32(Float32(2.0) * Float32(pi))) return fma(cos(t_0), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(Float32(yi * sin(t_0)) + Float32(Float32(Float32(1.0) - ux) * Float32(Float32(maxCos * ux) * zi)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := uy \cdot \left(2 \cdot \pi\right)\\
\mathsf{fma}\left(\cos t\_0, \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, yi \cdot \sin t\_0 + \left(1 - ux\right) \cdot \left(\left(maxCos \cdot ux\right) \cdot zi\right)\right)
\end{array}
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in maxCos around 0 99.1%
+-commutative99.1%
fma-define99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
Simplified99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in ux around 0 99.1%
*-commutative99.1%
*-commutative99.1%
associate-*r*99.1%
fma-define99.1%
associate-*l*99.1%
*-commutative99.1%
Applied egg-rr99.1%
Final simplification99.1%
(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 (* maxCos (- 1.0 ux)))))))
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 * (maxCos * (1.0f - ux))));
}
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(maxCos * Float32(Float32(1.0) - ux))))) 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 * (maxCos * (single(1.0) - ux)))); 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(maxCos \cdot \left(1 - ux\right)\right)\right)
\end{array}
\end{array}
Initial program 99.0%
Taylor expanded in ux around 0 99.0%
associate-*r*99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (+ (* 2.0 (* uy (* PI yi))) (* 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)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), ((2.0f * (uy * (((float) M_PI) * yi))) + (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(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * yi))) + 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), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, 2 \cdot \left(uy \cdot \left(\pi \cdot yi\right)\right) + maxCos \cdot \left(ux \cdot \left(\left(1 - ux\right) \cdot zi\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in maxCos around 0 99.1%
+-commutative99.1%
fma-define99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
Simplified99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in uy around 0 91.5%
Final simplification91.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (* maxCos (- (* ux zi) (* ux (* 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)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), (maxCos * ((ux * zi) - (ux * (ux * zi)))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(maxCos * Float32(Float32(ux * zi) - Float32(ux * Float32(ux * zi))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot zi - ux \cdot \left(ux \cdot zi\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in uy around 0 59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.5%
associate-*r*59.5%
sub-neg59.5%
distribute-rgt-in59.5%
*-un-lft-identity59.5%
Applied egg-rr59.5%
Final simplification59.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (* 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)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), (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(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), 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), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot \left(\left(1 - ux\right) \cdot zi\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in uy around 0 59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.5%
Final simplification59.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (* 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)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), (maxCos * (ux * zi)));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(maxCos * Float32(ux * zi))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot zi\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in uy around 0 59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 57.6%
Final simplification57.6%
herbie shell --seed 2024053
(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)))