Merge pull request #51565 from mortarroad/3.x-fix-cpu-particles-spread

[3.x] Fix CPU Particles spread
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Rémi Verschelde 2021-08-12 14:23:22 +02:00 committed by GitHub
commit 02541db309
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@ -694,15 +694,28 @@ void CPUParticles::_particles_process(float p_delta) {
p.velocity = rot * parameters[PARAM_INITIAL_LINEAR_VELOCITY] * Math::lerp(1.0f, float(Math::randf()), randomness[PARAM_INITIAL_LINEAR_VELOCITY]);
} else {
//initiate velocity spread in 3D
float angle1_rad = Math::atan2(direction.x, direction.z) + (Math::randf() * 2.0 - 1.0) * Math_PI * spread / 180.0;
float angle2_rad = Math::atan2(direction.y, Math::abs(direction.z)) + (Math::randf() * 2.0 - 1.0) * (1.0 - flatness) * Math_PI * spread / 180.0;
float angle1_rad = (Math::randf() * 2.0 - 1.0) * Math_PI * spread / 180.0;
float angle2_rad = (Math::randf() * 2.0 - 1.0) * (1.0 - flatness) * Math_PI * spread / 180.0;
Vector3 direction_xz = Vector3(Math::sin(angle1_rad), 0, Math::cos(angle1_rad));
Vector3 direction_yz = Vector3(0, Math::sin(angle2_rad), Math::cos(angle2_rad));
direction_yz.z = direction_yz.z / MAX(0.0001, Math::sqrt(ABS(direction_yz.z))); //better uniform distribution
Vector3 direction = Vector3(direction_xz.x * direction_yz.z, direction_yz.y, direction_xz.z * direction_yz.z);
direction.normalize();
p.velocity = direction * parameters[PARAM_INITIAL_LINEAR_VELOCITY] * Math::lerp(1.0f, float(Math::randf()), randomness[PARAM_INITIAL_LINEAR_VELOCITY]);
Vector3 spread_direction = Vector3(direction_xz.x * direction_yz.z, direction_yz.y, direction_xz.z * direction_yz.z);
Vector3 direction_nrm = direction;
if (direction_nrm.length_squared() > 0) {
direction_nrm.normalize();
} else {
direction_nrm = Vector3(0, 0, 1);
}
// rotate spread to direction
Vector3 binormal = Vector3(0.0, 1.0, 0.0).cross(direction_nrm);
if (binormal.length_squared() < 0.00000001) {
// direction is parallel to Y. Choose Z as the binormal.
binormal = Vector3(0.0, 0.0, 1.0);
}
binormal.normalize();
Vector3 normal = binormal.cross(direction_nrm);
spread_direction = binormal * spread_direction.x + normal * spread_direction.y + direction_nrm * spread_direction.z;
p.velocity = spread_direction * parameters[PARAM_INITIAL_LINEAR_VELOCITY] * Math::lerp(1.0f, float(Math::randf()), randomness[PARAM_INITIAL_LINEAR_VELOCITY]);
}
float base_angle = (parameters[PARAM_ANGLE] + tex_angle) * Math::lerp(1.0f, p.angle_rand, randomness[PARAM_ANGLE]);