When making clouds in Houdini, it’s important to remember their irregularity, density, texture, and lightning. These clouds are typically categorized as Volumes or VDBs. When creating clouds in Houdini, the primary factor at play is volumes, which are then converted into an attribute known as “Density”. In this project, we’ll explore the process of how I procedurally generated clouds, as well as incorporating elements like animation and Pyro effects.
Initially, my approach involved utilizing a high-resolution Sphere to generate VDBs with a more intricate and irregular shape. To further enhance the overall effect, I used the “Mountain” node which proved to be incredibly useful in terms of distorting the surface and introducing a greater degree of irregularity. This technique allowed me to achieve the desired outcome and create an optimal result.
After completing the initial distortion of the sphere, I proceeded to create duplicate copies of it. To ensure consistency, I made sure that each copy had identical attributes. However, to distinguish them from one another, I added a unique offset to each duplicate.
I added more details to the existing sphere by scattering some points and creating various sizes of regular spheres. These steps were taken to improve the overall quality of the sphere and convert it into VDBs.
Afterwards, I moved forward by transforming the shape into VDBs or volumes. To carry out this task, I used a node called “Cloud” which proves to be more efficient than the “VDB from Polygon node” when it comes to creating Cloud. The “Cloud” node provides a more extensive spectrum of components to operate with, enabling the designing of noise VDB.
Through the utilization of “Fill Source,” I have successfully generated a sphere with increased noise and irregularity on the VDB. This newly created volume will prove to be quite beneficial in generating a more diverse and dynamic noisy volume.
To achieve a more lifelike appearance, I utilized the Cloud Noise node to enhance the realism of the clouds. This resulted in a more natural-looking noise in the Volume, which helped to create a more irregular cloud pattern. Additionally, I fine-tuned the Density using the Cloud Noise node to accurately emulate the fluctuating density of real-world clouds, which can range from virtually nonexistent to a fully dense state.
As a result of the extensive time required for rendering Volumes, I found it necessary to implement several measures to ensure an efficient process. I decided to limit the camera resolution and adjust certain elements like SSS, Volume quality, and Noise to achieve the desired outcome. Despite these limitations, I am happy to report that the clouds have retained their natural, irregular shapes and variations in their density, resulting in a pleasing final product.