Continuing on from the last week, I played around with values for the “POP grains” node to see if I could get to a point where the sand would fall the way I wanted it to. I noticed that it would take a long time for my computer to process, and it took me almost a whole day to get various appearances. Here are just a few of what I did:
However, I did find that it would almost be impossible to achieve that realistic look, just through “pop grain” and adjusting values from within. Later during the week, I had a call with Mehdi, who suggested a different approach in order to achieve my realistically looking falling sand. Instead of focusing on the whole system as one, he suggested breaking it down into 3: the sand on top of the hourglass the level of which is decreasing, a source that emits the falling sand grains in the narrow part of the hourglass and the pile of sand on the bottom that raises up in the way I want it to.
Instead of using just “pop solver”, for some areas “vellum solver” will be applied to get faster computer processing and even better-looking results. This is what my focus will be to finish during this week.
I also started on the fire case, for which I set up the scene just as in the hourglass. After importing the alembic cache files from Maya, I divided the case into its various parts and started creating the fire source.
After reading in the base, I deleted some of its polygons, in order to have the main ones from which the fire will be simulating. Points were scattered across those upwards-facing polygons, further applied the “pyrosource”, to create the required attributes for the fire simulation: density, temperature, velocity, and fuel. Then the noise was applied to the density, to have fire simulated from various points during each frame and add more randomization to it. Just as in all fire simulations, the “volume rasterize attributes” node had to be applied before finally simulating it in the “pyrosolver”. I’ve also read in the fire case, changed to a VDB, such that it could be used as the collision source.
Here is a playblast of how the fire looked just in the viewport.
In order to see how it will actually look like, I need to set up the lights and materials, such that I could get a rendered image. The way fire looks rendered and in the viewport is always different. I also want to know if I have enough voxels for the details or if I have to make more. As this was very easy and quick to set up, I decided that I will go ahead and make a crystal in Houdini, to make it look like it’s on fire, instead of a simple fire coming from the base.
For the next week, I will focus on creating scenes in Houdini for the particle swirls simulation and the backflow incense burner. Then I will have enough time to perfect them and in case of any problems, set up a meeting with Mehdi for some help. I will also need to think about the textures applied to the objects and if I have enough time to actually set everything up, then run some renders.