FXPHD – HOU170 – Impact-Based Dust Volumetrics in Houdini

关键的体积组件支持任何出色的外观效果。让灰尘和颗粒的体积云正确移动和渲染，对于大三学生来说通常是一项具有挑战性的任务。本课程侧重于根据影响生成漂亮的体积灰尘，并让您准备好将这些类型的模拟应用于艺术指导。

本课程从准备和优化资产开始，为镜头制作过程中的快速迭代做好准备。然后通过构建烟雾模拟网络深入了解 DOP 的可怕世界，这将使您能够揭开和掌握工作流程的神秘面纱。在研究量源排放的关键步骤时将非常小心。您将看到如何避免步进，以及通过从 RBD 动画中提取有用数据，在模拟中注入尽可能多的细节。

碰撞也将被涵盖，我们将看到如何正确地可视化它们以解决任何与碰撞器相关的问题。并且将单独添加速度噪声以更好地控制我们的发射。最后，由于 DOP 微解算器，我们将通过分层力进一步指导和复杂化我们的模拟。为了帮助我们完成这项任务，我们将构建我们自己的场并将它们用作掩码来精确干扰或抑制我们模拟的相关部分。

灯光和渲染的重要部分也将被覆盖，在这个过程中使用 Mantra。您将看到如何使用灯光塑造体积并揭示其更精细的细节。涵盖了 Houdini 的烟雾火焰着色器，以及学习如何从灯光和模拟场中提取有用信息以构建 AOV、阴影通道以及用于合成的技术通道。

从阻止模拟到选择最终渲染分辨率，我们将针对迭代速度构建和自动化我们的工作流程，这是任何镜头制作过程的关键。并且因为 FX 模拟可能非常消耗工作室的基础设施，特别是在楔入参数以找到正确的值时，您将看到如何优化数据并仅在需要时缓存所需的数据。这将使艺术家能够快速适应艺术方向的修订和变化。

FXPHD – HOU170 – Impact-Based Dust Volumetrics in Houdini | Taught by Bruno Ebe

Any great looking impact is supported by the crucial volumetric component. Getting volumetric clouds of dust and particulates moving and rendering correctly can often prove a challenging task for juniors and seniors alike. This course focuses on generating great looking volumetric dust based on impacts and preparing you to be able to adapt these types of simulations to art direction.

The course begins with preparing and optimizing the assets to ready them for fast iteration during the shot production process. It then dives into the often scary world of DOPs by building a smoke simulation network, which will allow you to both demystify and master the workflow. Great care will be taken in studying the crucial step of the volume sourcing emission. You will see how to avoid stepping, as well as inject as many details in the simulation right from the emission by extracting useful data from the RBD animation.

Collisions will be covered as well, and we will see how to visualize them correctly to troubleshoot any collider related issue. And velocity noise will be added separately to have finer control on our emission. Finally, we will further direct and complexify our simulation by layering forces thanks to DOP micro-solvers. To assist us in this task, we will build our own fields and use them as masks to precisely disturb or damp relevant parts of our simulation.

The important part of lighting and rendering will also be covered, using Mantra in this process. You will see how to use lights to shape the volume and reveal its finer details. Houdini’s Pyro shader for smoke is covered as well as learning how to extract useful information from lights and simulation fields to build AOVs, shadow passes, as well as technical passes for compositing.

From blocking the simulation to choosing the final render resolution, we will build and automate our workflow aiming at iteration speed, which is key in any shot production process. And because FX simulations can be very consuming and demanding on a studio’s infrastructure, especially when wedging parameters to find the right values, you will see how to optimize the data and cache only what is needed when it is needed. This will allow the artists to adapt them quickly to revisions and changes in the art direction.