Image Sequence Textures for Particles failing
Closed, InvalidPublic

Description

System Information
WIndows 10 Pro, 64-bit GeForce GTX 690

Blender Version
Broken: 2.78b 3c04373

Short description of error
Baked Canvas, Brush images (png) won't refresh to affect particles for animation as image sequence. UPDATE: Things only behave with particles set to Grid in Emission section.

Exact steps for others to reproduce the error
Brush following Curve over Canvas - bake as images to folder.
Particle system on Canvas. Textures, New.
In Textures Tab, Image or Movie with first image, then Image Sequence.
The Frames ("number of images in a movie to use") is buggy obeying your current Frame Position but reporting the entry you key in.
Checking Auto Refresh seems to have no effect.
Any Influence, Density, Size, etc is updated in Preview and Render only when you return to Particles Tab and fiddle with some portion in Emission settings.

It's hard to be exact because so much is unpredictable and not behaving as expected. I just want to animate cutting grass! Bake the lawn mower path, use it to alter grass particles sizes and densities. It's not a popular or sexy problem, but the behavior must extend to other effects where Particles and Textures are concerned over Vertex Groups; hair, particle crowds, other SFX.

Details

Type
Bug

Particles emission does not support animated weight groups, animated textures or image sequence textures.
It is a known limitation of current particle systems.

None of settings present under General label in Influence panel of Texture Tab can be animated.
Of course Time and Lifetime settings can conduct to particles animations.
But the whole emission is contained into one image where a black pixel meams start of emission or no life and a white one end of emission or maximum lifetime.

This kind of animation are usually made by using hair particles.
For these particles, settings under Hair label in Influence panel of Texture Tab can handle Image Sequence Textures.
An hair particle system can handle an annimated weight group to control length of particles.
But it can't handle an animatied weight group to control Density.

Density is fixed.
But when particles are animated to jump from a certain length or life e to none ; we have a decent illusion of animation of density.

I appreciate your in depth response. I wasn't able to use an Image Sequence by baking paint but was able to use the Weight to bake something for an Animated Weight Group. I never knew that was possible and I'll keep experimenting and learning.

Before reading your answer, I more or less got Grid to behave in a way that I thought I could use but Hair overall is much better.

So this is probably closed now or maybe wasn't an issue in the first place. Thanks for your patience!

Luca Rood (LucaRood) closed this task as "Invalid".Sun, Mar 26, 2:56 PM
Luca Rood (LucaRood) claimed this task.

It seems that @ronan ducluzeau (zeauro) clarified the issue, and that there is no bug here after all. Closing.