UPD: I replaced animations with shaders for now.
My plan was to make effects like in this video.
Right now it feels like a good solution. (Video).
(Smoothstep example here imitates a line in a video, white noise there makes glow more interesting; I also enabled "glow" filter in camera options.)
Code for a ShaderMaterial:
shader_type spatial;
render_mode cull_disabled;
float rnd (vec2 st) {
return fract(
sin(
dot(st.xy,
vec2(12.9898,78.233))
) * 43758.5453123
);
}
void fragment() {
vec2 ipos = ceil(UV * 40.0);
float d = 0.0;
d += smoothstep(
.05,
.005,
abs(sin(TIME)) - UV.y
);
d *= rnd(ipos + TIME);
ALBEDO = vec3(d);
ALPHA = d;
EMISSION = vec3(d) * 6.0;
}
Still, it will be very nice to know how to do animations, which are independent from each other.