avfilter/vf_v360: simplify ball_to_xyz() calculations

This commit is contained in:
Paul B Mahol 2019-09-21 16:21:36 +02:00
parent ecaef69fbb
commit 34046bcd5f
1 changed files with 4 additions and 10 deletions

View File

@ -1643,17 +1643,11 @@ static void ball_to_xyz(const V360Context *s,
const float l = hypotf(x, y);
if (l <= 1.f) {
const float phi = atan2f(x, y);
const float theta = 2.f * asinf(l);
const float z = 2.f * l * sqrtf(1.f - l * l);
const float sin_phi = sinf(phi);
const float cos_phi = cosf(phi);
const float sin_theta = sinf(theta);
const float cos_theta = cosf(theta);
vec[0] = sin_theta * sin_phi;
vec[1] = -sin_theta * cos_phi;
vec[2] = -cos_theta;
vec[0] = z * x / (l > 0.f ? l : 1.f);
vec[1] = -z * y / (l > 0.f ? l : 1.f);
vec[2] = -1.f + 2.f * l * l;
} else {
vec[0] = 0.f;
vec[1] = -1.f;