Description: After seeing a few demonstrations of the BiFrost particle system built into Maya, I decided I wanted to figure a few things out with it. It seems to be a pretty powerful and intuitive system that I could utilize in future projects.
I want to use this project to learn the basics of BiFrost and create a simple scene. I only plan on making this a still image, and I can work on animation later. My idea is to create a dynamic image of wine pouring into a glass.
Modeling / Scene Setup: I really wanted to keep the scene simple, so I created a backdrop wall, a wine bottle, a wine glass, and a table with a table cloth.
Both the wine bottle and glass were modeled to be accurate in a working sense, and thus retain the thickness they would in real life. To each of these, I created glass shaders utilizing mia_material_x shaders. To the wine bottle, I added a green tint to the glass.
The table cloth I applied a red shader to. Although it does not appear in the image itself, it did provide reflective light and affect the ambient occlusion. It can be subtly seen in the reflection of the glass as well.
The wall is a simple plane. To it, I applied a diffuse tan shader. I chose the tan/beige color as it contrasts well, and compliments the red wine I intended to create. I also applied a bump map utilizing fractal noise to create spackled look that dry-wall typically has.
For the lighting, I went with a 3 point lighting set-up: key, fill, and rim. All three were spotlights with a warm yellow light. I set the cone angle to 90 and the penumbra angle to -19 to create a soft falloff.
The wine bottle cast a very weird shadow that detracted from the image, so I turned off shadows from my key light. This ultimately made the shot look better, and I didn’t lose anything by dropping it.
Originally, I had the decay rate for the light set to quadratic, but this required me to up my light intensity drastically, and that resulted in a blown-out liquid. So I returned to a setting of no decay, and the result appeared to be fine.
BiFrost: To create the BiFrost liquid, I decided to go very simple, and not get too involved here. After all, I was going for simplicity with this particular project. I created a small cylinder and put it inside of my wine bottle towards the back. I made the cylinder be the BiFrost liquid emitter. I then set the bottle and the glass to be colliders for the liquid.
The voxel size was too large initially, however, as the particles wound up getting stuck inside of the bottle. I then set the voxel size to .05 and this allowed for the particles to smoothly flow out. By placing the emitter at the back of the bottle, it also allowed for the particles to recover from the initial emitting process and act more like a flowing liquid than a splashing liquid.
To change the color of the liquid, I went into the hypershade editor and changed both the diffuse and reflected color to a deep red.
Conclusion: I think the final result looks pretty good. I believe I accomplished what I set out to with this particular project, and I have some direction on where I’d like to go with it, as well as where I need to look to improve.
I think that while the liquid looks good, there is something off that makes it look more like red water than it does like wine. I believe this has something to do with the refractive qualities between water and alcohol - I intend to look into this.
The render times were much too high, and I had to sacrifice certain rendering qualities to keep render times to a somewhat reasonable level. But at 20 minutes to render a frame, without shadows, and low settings in ambient occlusion and final gather, I will need to work on the efficiency if I intend to create an animation or anything more complex than this piece.