I created a particle simulation that emits icospheres with 0 gravity, but affected by a wind force field, with the intent to make it look like it's being blown away by the wind. I'd like to render this animation in Keyshot, so I have to export this file as an Alembic. I used a Python script posted by jasperge to convert the particle simulation into meshes.
The script ran successfully, but playing the animation shows that the particles are gigantic. Anyone have an idea why this may be, or if there's something I need to change in the script? I'd appreciate any help. Thanks!
Before script:
After script:
Script used:
import bpy
# Set these to False if you don't want to key that property.
KEYFRAME_LOCATION = True
KEYFRAME_ROTATION = True
KEYFRAME_SCALE = True
KEYFRAME_VISIBILITY = True # Viewport and render visibility.
def create_objects_for_particles(ps, obj):
# Duplicate the given object for every particle and return the duplicates.
# Use instances instead of full copies.
obj_list = []
mesh = obj.data
for i, _ in enumerate(ps.particles):
dupli = bpy.data.objects.new(
name="particle.{:03d}".format(i),
object_data=mesh)
bpy.context.scene.objects.link(dupli)
obj_list.append(dupli)
return obj_list
def match_and_keyframe_objects(ps, obj_list, start_frame, end_frame):
# Match and keyframe the objects to the particles for every frame in the
# given range.
for frame in range(start_frame, end_frame + 1):
bpy.context.scene.frame_set(frame)
for p, obj in zip(ps.particles, obj_list):
match_object_to_particle(p, obj)
keyframe_obj(obj)
def match_object_to_particle(p, obj):
# Match the location, rotation, scale and visibility of the object to
# the particle.
loc = p.location
rot = p.rotation
size = p.size
if p.alive_state == 'ALIVE':
vis = True
else:
vis = False
obj.location = loc
# Set rotation mode to quaternion to match particle rotation.
obj.rotation_mode = 'QUATERNION'
obj.rotation_quaternion = rot
obj.scale = (size, size, size)
obj.hide = not(vis)
obj.hide_render = not(vis)
def keyframe_obj(obj):
# Keyframe location, rotation, scale and visibility if specified.
if KEYFRAME_LOCATION:
obj.keyframe_insert("location")
if KEYFRAME_ROTATION:
obj.keyframe_insert("rotation_quaternion")
if KEYFRAME_SCALE:
obj.keyframe_insert("scale")
if KEYFRAME_VISIBILITY:
obj.keyframe_insert("hide")
obj.keyframe_insert("hide_render")
def main():
# Assume only 2 objects are selected.
# The active object should be the one with the particle system.
ps_obj = bpy.context.object
obj = [obj for obj in bpy.context.selected_objects if obj != ps_obj][0]
ps = ps_obj.particle_systems[0] # Assume only 1 particle system is present.
start_frame = bpy.context.scene.frame_start
end_frame = bpy.context.scene.frame_end
obj_list = create_objects_for_particles(ps, obj)
match_and_keyframe_objects(ps, obj_list, start_frame, end_frame)
if __name__ == '__main__':
main()
