Make hundres of objects (letters) automatically appear at different times

Artistic Support Animation and Rigging
1

Blender 2.64:

I have a text (svg import). Each letter is one object (and initially each has its own color (though each color look exactly the same)). I want the letters to appear (or better: fade in) at random times; so initially, no letters are visible and as time goes by more and more letters (not in the reading order, but a random order) pop up/fade in until finally the whole text is visible.

Unfortunately, I have no idea how to automatically solve this.

Any ideas or hints are highly appreciated
blackno666

2

You could do this manually, just give each letter its own material and animate each one to change the alpha value from 0 to 1.
Or, if you just have the letters static and they’re not overlapping, you could just render out the text into a separate renderlayer, then model a flat object, so that each letter is represented by one face. The use the Build modifier set to Random to randomly let these faces appear.
Combine the text layer and the random face layer using nodes, for example, multiply the alpha channels. Maybe play around with that a bit. That should make the letters appear at random. Doesn’t fade them in though.

3

here a simple script to animate alpha on many objects as nemoDaedalus suggested…
see each object needs its own material, -use Ukey for that-


# min_frame, max_frame, length
min, max, len = 1, 50, 25
import bpy, random

for obj in bpy.context.selected_objects:
    obj.data.materials[0].use_transparency = True
    obj.data.materials[0].use_transparent_shadows = True
    f = int ( random.random() * (max-min) + min ) # choose a frame
    obj.data.materials[0].alpha = 0
    obj.data.materials[0].keyframe_insert(data_path="alpha", frame=f)
    obj.data.materials[0].alpha = 1
    obj.data.materials[0].keyframe_insert(data_path="alpha", frame=f+len)
4

Thanks for the ideas,

I have a text which consists - as mentioned in the topic - of hundreds of letters. I was aware of animating the materials, but this would be more than tedious.

The build modifier is a nice idea; however, since I don’t use an equal-spaced font (as “Courier” would be), I would have to manually create faces for each letter (I guess).

Probably scripting would be easy as well…

5

Liero,

exactly what I was looking for. I hadn’t seen your answer when I posted my last entry.

Thanks!

6

I am finishing up a project that does this (kinda)…

To make the letters “appear” I used location key frames and constant interpolation. They are not there, “poof” they are there. For the fading I used an alpha texture that went from "transparent to “blue” The material color white and I wanted the letters to fade from white to blue, but I wanted them to do it from one side of the letter to the other not the entire letter at the same time. For this I used an alpha texture That faded, from one side to the other.

Here is the (undone) project with the fading letters:

Here it is with the letters “magically appearing”

Hope that helps…