diff options
Diffstat (limited to 'scene/resources/particles_material.cpp')
| -rw-r--r-- | scene/resources/particles_material.cpp | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/scene/resources/particles_material.cpp b/scene/resources/particles_material.cpp index a0f4bf9409..195ce070a7 100644 --- a/scene/resources/particles_material.cpp +++ b/scene/resources/particles_material.cpp @@ -340,14 +340,21 @@ void ParticlesMaterial::_update_shader() { //initiate velocity spread in 3D code += " float angle1_rad = rand_from_seed_m1_p1(alt_seed) * spread_rad;\n"; code += " float angle2_rad = rand_from_seed_m1_p1(alt_seed) * spread_rad * (1.0 - flatness);\n"; - code += " angle1_rad += direction.z != 0.0 ? atan(direction.x, direction.z) : sign(direction.x) * (pi / 2.0);\n"; - code += " angle2_rad += direction.z != 0.0 ? atan(direction.y, abs(direction.z)) : (direction.x != 0.0 ? atan(direction.y, abs(direction.x)) : sign(direction.y) * (pi / 2.0));\n"; code += " vec3 direction_xz = vec3(sin(angle1_rad), 0.0, cos(angle1_rad));\n"; code += " vec3 direction_yz = vec3(0.0, sin(angle2_rad), cos(angle2_rad));\n"; code += " direction_yz.z = direction_yz.z / max(0.0001,sqrt(abs(direction_yz.z))); // better uniform distribution\n"; - code += " vec3 vec_direction = vec3(direction_xz.x * direction_yz.z, direction_yz.y, direction_xz.z * direction_yz.z);\n"; - code += " vec_direction = normalize(vec_direction);\n"; - code += " VELOCITY = vec_direction * initial_linear_velocity * mix(1.0, rand_from_seed(alt_seed), initial_linear_velocity_random);\n"; + code += " vec3 spread_direction = vec3(direction_xz.x * direction_yz.z, direction_yz.y, direction_xz.z * direction_yz.z);\n"; + code += " vec3 direction_nrm = normalize(direction);\n"; + code += " // rotate spread to direction\n"; + code += " vec3 binormal = cross(vec3(0.0, 1.0, 0.0), direction_nrm);\n"; + code += " if (length(binormal) < 0.0001) {\n"; + code += " // direction is parallel to Y. Choose Z as the binormal.\n"; + code += " binormal = vec3(0.0, 0.0, 1.0);\n"; + code += " }\n"; + code += " binormal = normalize(binormal);\n"; + code += " vec3 normal = cross(binormal, direction_nrm);\n"; + code += " spread_direction = binormal * spread_direction.x + normal * spread_direction.y + direction_nrm * spread_direction.z;\n"; + code += " VELOCITY = spread_direction * initial_linear_velocity * mix(1.0, rand_from_seed(alt_seed), initial_linear_velocity_random);\n"; } code += " }\n"; |