Method project_input

src/effects/SphericalProjection.cpp:374–420

}

void SphericalProjection::project_input(double dx, double dy, double dz,
										double in_fov_r, int W, int H,
										double &uf, double &vf) const {
	if (input_model == INPUT_EQUIRECT) {
		// Center (-Z) -> lon=0; +X (screen right) -> +lon
		double lon = std::atan2(dx, -dz);
		double lat = std::asin(std::clamp(dy, -1.0, 1.0));

		if (projection_mode == MODE_RECT_HEMISPHERE)
			lon = std::clamp(lon, -M_PI / 2.0, M_PI / 2.0);

		double horiz_span = (projection_mode == MODE_RECT_HEMISPHERE) ? M_PI : 2.0 * M_PI;
		double lon_offset = (projection_mode == MODE_RECT_HEMISPHERE) ? M_PI / 2.0 : M_PI;
		uf = ((lon + lon_offset) / horiz_span) * W;

		// Image Y grows downward: north (lat = +π/2) at top
		vf = (M_PI / 2.0 - lat) / M_PI * H;
		return;
	}

	// -------- Fisheye inputs --------
	// Optical axis default is -Z; "Invert" flips hemisphere.
	const double ax = 0.0, ay = 0.0;
	double az = -1.0;
	if (invert == INVERT_BACK) az = 1.0;

	double cos_t    = std::clamp(dx * ax + dy * ay + dz * az, -1.0, 1.0);
	double theta    = std::acos(cos_t);
	double tmax     = std::max(1e-6, in_fov_r * 0.5);

	double r_norm = 0.0;
	switch (input_model) {
	case INPUT_FEQ_EQUIDISTANT:            r_norm =                theta            / tmax; break;
	case INPUT_FEQ_EQUISOLID:                r_norm = std::sin(theta*0.5) / std::max(1e-12, std::sin(tmax*0.5)); break;
	case INPUT_FEQ_STEREOGRAPHIC:        r_norm = std::tan(theta*0.5) / std::max(1e-12, std::tan(tmax*0.5)); break;
	case INPUT_FEQ_ORTHOGRAPHIC:         r_norm = std::sin(theta)         / std::max(1e-12, std::sin(tmax));         break;
	default:                                                 r_norm =                theta            / tmax; break;
	}

	// Azimuth in camera XY; final Y is downward -> subtract sine in vf
	double phi = std::atan2(dy, dx);

	double R     = 0.5 * std::min(W, H);
	double rpx = r_norm * R;
	uf = W * 0.5 + rpx * std::cos(phi);
	vf = H * 0.5 - rpx * std::sin(phi);
}

std::string SphericalProjection::Json() const
{