Material IPOS Not working


(darkstar1) #1

I have an animation and need to use the alpha keys. However I insert keys and I everything seems right. But when I render parts with high alpha values it shows nothing, and when returning to blender the alpha turns into Alpha 0.000. I made sure there are keys raising the value and when in the IPO window when I go through the animation with the directional keys alpha values raise and drop like they are suppose to but rendering they are always at 0.000. (the animation has the item starting with alpha 0.00 but raises then lowers) I never had this problem in the past any answers?

The problem only occurs with my particles, however it the alpha is working with the ship.


(tHe-IcemAn) #2

Material IPOS with particles do nopt rely on frame number, they rely on the life of the particle itself.


(darkstar1) #3

So how in @ce’s blend file of an explosion he was able to use alpha and halo size keys for his particles?


(Koryo) #4

Hello darkstar1,

Material IPOs on particles are mapped so that frame 1 is the beginning of the
particle’s life and frame 100 is the end of its life. I.e. If I have a particle
system with a mean lifetime of 30 frames, frame 1 in the material IPO is
frame 1 of a particle’s life and frame 100 in the material IPO is frame 30
of the particle’s life.

I hope this helps.


(darkstar1) #5

I sort of understand,
I created a test blend and your theory seems false, but I’m not sure being very new to blender. But when I made a quick particle system with start frame 1 and end 3, life of 130, I was able to add alpha keys at frames 16 and 22 without any problems. I think it could be something in my blend file because I see the keys there but when I render it seems to just ignore it and go to 0. However I do appreciate your suggestion. I still have this problem to deal with but also another, how can I make my wav files to play at certain frames? Answers to both would be extremely helpful.


(mikejedw) #6

I’ve having the same problem. I can get the IPOs to look right, I can get the material in the material buttons window (increasing the alpah and haSize) to adjust as I step through the animation (100 frames), but in the render itself, I’m only seeing the values from the first frame. If I set the alpha to be 100% in the first frame instead of zero, I see 100% all the way through. This happened today ona smoke animation I’m making as well as in the past with the various campfire tutorials. Any suggestions? I’ve fiddled with the particle life, but I haven’t had any luck.


(theeth) #7

Koryo’s explanation is correct, but maybe you need a little more explanation.

When keyframing a material animation for halo particles, the first 100 frames (frame 1 to 100) of the IPO will be mapped on each particles individually, the whole 100 frames correcponding to 100% of the particles life.
Lets say, for example, that you have a particle emitter shooting 200 particles from frame 10 to 30, every particle with a life of 10 frames.

Frame 1 to 9: nothing happens
Frame 10: 10 new particles are created, their material is determined by looking at frame 1 on the IPO
Frame 11: the 10 particles from frame 10 are mapped using data from frame 10 on the IPO, since they are at 10% of their life. 10 new particles are also spawned, and acts like the one created on frame 10, taking their material data on frame 1 of the IPO.

and so on

I hope that was more clear.

Martin


(mikejedw) #8

OOOOOOOOO! Man, that makes a lot of sense now. I had the whole thing wrong in my head. What I was trying to do was make the emitter spit out smaller and lighter particles over time BUT what the IPO actual does is to make that transition on the life a given particle, making the particle itself smaller and lighter, not the next generation of particles like that. I was thinking “fade out” in terms of the fire dying and not in terms of the fire’s particles gradually dissipating. Yeeesh, that clears up a lot–my brain was turned 90 degress from everything. I’ve seen other posts where people have basically been asking my same question, not grokking the difference.

Thanks!