View Full Version : Growing Blades of Grass

07-29-2010, 06:22 PM
I need to create a field of grass that grows before my eyes.

My thinking is that it starts with a big particle emitter. That's about as far as I can figure out!

Each blade appears when the particle does. Perhaps it does a scale up and rotation a bit based on time: zero to fully grown in 30 frames.

Can anyone direct me to a tutorial or how would you handle this?

I saw a video involving splashes triggered by collision that got me thinking about using particles.


Thanks everyone!

07-29-2010, 07:56 PM
I'm using clip maps on sprites and that seems to be working.

07-29-2010, 09:49 PM
This turned out so great I want to share it with the LW community.

It's a particle animation. I realized there's a 1 million particle limit, as this animation has 500k particles in the end. This test is about 2/3 the way to the end.

The blade graphic is a clip map added to a sprite hypervoxel, except for the first blade which is geometry.

It's interesting that the rendering has only 100 polygons - the blade, the pebbles, and the shadowcatching plane.

The particles have a little negative gravity and 'stick' to the ground plane. Notice they seem to grow -a totally effective cheat.

Top it all off with the awesome fisheye lens and photoreal motion blur.

This is going to be an element in another layer of motion graphic. So I'm not done yet but the effect has sold me on the concept. It's for a lawn care company.

07-29-2010, 09:55 PM
That looks really cool.

I will have to keep this technique in mind.

07-30-2010, 03:20 AM
Actually you dont need to use particles at all. I typically pick points off the ground object and paste them into another layer.
In layout Ill apply HV sprites to that 2nd layer and use textures to drive the growth by the placement and intensity of the texture (in the size channel).