User manual PYROCLUSTER CINEMA 4D 9

PyroCluster PyroCluster Programming Team Christian Losch, Philip Losch, Richard Kurz, Tilo Kühn, Thomas Kunert, David O'Reilly, Cathleen Poppe. Plugin Programming Sven Behne, Wilfried Behne, Michael Breitzke, Kiril Dinev, Per-Anders Edwards, David Farmer, Jamie Halmick, Richard Hintzenstern, Jan Eric Hoffmann, Eduardo Olivares, Nina Ivanova, Markus Jakubietz, Eric Sommerlade, Hendrik Steffen, Jens Uhlig, Michael Welter, Thomas Zeier. Product Manager Marco Tillmann. QA Manager Björn Marl. Writers Paul Babb, Rick Barrett, Oliver Becker, Jens Bosse, Chris Broeske, Chris Debski, Glenn Frey, Michael Giebel, Jason Goldsmith, Jörn Gollob, Sven Hauth, Josiah Hultgren, Arndt von Königsmarck, David Link, Arno Löwecke, Aaron Matthew, Josh Miller, Matthew `Mash' O'Neill, Janine Pauke, Marcus Spranger, Luke Stacy, Perry Stacy, Marco Tillmann, Jeff Walker, Scot Wardlaw. SDK Docs & Support David O'Reilly, Mikael Sterner. Layout Oliver Becker, Harald Egel, Michael Giebel, David Link, Luke Stacy, Jeff Walker. Translation Oliver Becker, Michael Giebel, Arno Löwecke, Björn Marl, Josh Miller, Janine Pauke, Luke Stacy, Marco Tillmann, Scot Wardlaw. Copyright © 1989-2004 by MAXON Computer GmbH. All rights reserved. English translation Copyright © 2004 by MAXON Computer Ltd. All rights reserved. This manual and the accompanying software are copyright protected. No part of this document may be translated, reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written permission of MAXON Computer. Although every precaution has been taken in the preparation of the program and this manual, MAXON Computer assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the program or from the information contained in this manual. 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Contents Introduction........................................................................................................................................... 1 Reference ..............................................................................................................5 Overview................................................................................................................................................ 5 Creating a PyroCluster Effect ................................................................................................................ 8 Settings for the Volume Tracer Material .............................................................................................. 11 Gradients ............................................................................................................................................. 15 Using gradients............................................................................................................................... 15 The gradient and its options........................................................................................................... 16 The context menu for gradients ..................................................................................................... 17 Working with gradients.................................................................................................................. 17 Setting colors.................................................................................................................................. 18 Particle settings .............................................................................................................................. 18 The power of life and death ........................................................................................................... 18 Animating colors ............................................................................................................................ 19 Settings for the PyroCluster Shader .................................................................................................... 22 Basic Properties page ..................................................................................................................... 22 Globals page................................................................................................................................... 22 Age page ........................................................................................................................................ 29 Distance page ................................................................................................................................. 31 Cylindrical Distance page ............................................................................................................... 33 Shape page ..................................................................................................................................... 35 Illumination page............................................................................................................................ 38 Shadow page .................................................................................................................................. 42 Noise page ...................................................................................................................................... 46 Animating PyroCluster parameters ..................................................................................................... 52 Choosing Light Sources ....................................................................................................................... 53 Tutorials...............................................................................................................57 Gradient Animation ............................................................................................................................. 57 Keyframe Animation............................................................................................................................ 61 Index....................................................................................................................67 PYROCLUSTER INTRODUCTION 1 Introduction From fire to water, from hot rocks to cool mists, PyroCluster puts you in control of countless volume effects that will add realism to your stills and your animations. PyroCluster is a module for CINEMA 4D that provides a powerful toolset for creating such effects as realistic clouds, haze, fire and smoke. With PyroCluster, in a single module you have literally an unlimited number of volume effects. PyroCluster effects are real 3D effects that will work with any CINEMA 4D-compatible particle system. Spectacular PyroCluster effects can be combined with, for example, the powerful animation features of the optional Thinking Particles module. PyroCluster is fully compatible with the optional Thinking Particles module; see your Thinking Particles manual for an example of how to combine these two particle modules. For more information on Thinking Particles, please contact your local MAXON dealer or visit www.maxon.net. All effects are based on particles; each particle becomes a `puff' and is rendered as a real volumetric effect. A particle's color can be determined by its age and a gradient controller. This makes it easy, for example, to create white smoke at the beginning and a dark oily smoke at the end of the particle's life span. An unlimited number of spectacular volume effects are possible with PyroCluster, including (but not limited to) vapory effects, solid rock effects and pyroclastic effects. To guarantee a flawless integration into CINEMA 4D, many new programming techniques have been developed. One of the amazing new technologies, developed exclusively for the CINEMA 4D PyroCluster module, is the centralized atmospheric tracer engine. This technology makes it possible to mix multiple volumetric effects in a scene. Volume lights and PyroCluster effects will automatically combine correctly, even casting volumetric shadows ­ indeed, PyroCluster supports shadow casting with any light source. Registration Registering your PyroCluster module is extremely important. The serial number included with your PyroCluster package is temporary and it will expire three months after the module's installation. To receive your final serial number, you must register. So please fill in and return the registration form at the earliest opportunity. Registering your PyroCluster module will also entitle you to technical support via telephone, fax and email. By checking the appropriate box on the registration form, MAXON will keep you informed of the latest product information and updates. You can also register online at register.maxon.net. 2 INTRODUCTION PYROCLUSTER Installation To install PyroCluster, run the installation program and follow the on-screen instructions. The installation program will create a PyroCluster folder in your CINEMA 4D Modules folder. The installation program will place all the CINEMA 4D PyroCluster files into this PyroCluster folder. Training Training is available for PyroCluster and other MAXON products. For details, please contact MAXON or your local MAXON distributor. Web Resources Thousands of powerful resources are available on the web, including online tutorials, discussion lists, textures, models, galleries and information on 3D books. You will find links to a rich selection of these sites at www.maxon.net. One website that you may wish to bookmark is www.plugincafe.com, the home of CINEMA 4D plugins. Here you will find dozens of useful plugins, both free and commercial. For plugin developers, there are resources, including the SDK, tutorials and a free support forum. Lastly, there is the MAXON website itself, www.maxon.net. In addition to the links mentioned above, it is from here that you can register your MAXON product, download updates, send MAXON a suggestion, check out the gallery, learn from online tutorials and much more. Technical Support Your local MAXON distributor will be delighted to assist you with your technical queries for PyroCluster. You are also welcome to contact MAXON directly. Please note that you will be entitled to technical support provided you have registered your PyroCluster module (see Registration, above). 1 Reference PYROCLUSTER REFERENCE 5 Overview Driven by a high quality, volumetric render engine, PyroCluster enables you to produce truly spectacular realistic effects. Volumetric effects are among the most spectacular of all 3D effects, especially when animated. PyroCluster can not only be used to create regular volumetric effects such as smoke and haze, but it is also perfect for fiery or solid liquid effects. The name `PyroCluster' is borrowed from a natural phenomenon called a pyroclastic cloud. Pyroclastic clouds, a mixture of superheated gases and small dust particles, are often the cause of an erupting volcano and they may end up killing more people than the actual eruption. A seriously powerful phenomenon, and PyroCluster is a seriously powerful addition to your 3D toolkit. PyroCluster works in conjunction with particle systems by adding a procedural volume around each particle. Particles can be generated using CINEMA 4D's default particle system, the optional Thinking Particles module or any other particle system that is compatible, and the particles can be manipulated using any of the controls for that system, including such forces as gravity, wind, friction and collision. 6 REFERENCE PYROCLUSTER PyroCluster employs a unique interface that utilizes gradients to control the effect. Gradients control the color, age, scale animation and variation of each PyroCluster volume. By simply sliding or editing color boxes you can change the PyroCluster effect dramatically. Presets for fire, smoke, clouds, steam and volcanic ash can be used as is, or edited further to achieve the look you desire. Many kinds of gaseous cloud effects are possible. A realtime preview window displays the look of the PyroCluster effect as you make changes, so you can get just the effect you want. What's more, all of PyroCluster's parameters are accessible through XPresso, CINEMA 4D's node editor, so you can use sliders or other objects in the scene to adjust the PyroCluster effect. With this high degree of control, you can make everything from fire and snow to smoke trails look realistic and exciting. Realistic, animated vapor trails add enormous impact to a scene. PYROCLUSTER REFERENCE 7 Advanced optimization features in the PyroCluster Volume Tracer (the bit that actually does the rendering) offer many ways to improve render speed and quality. For example, PyroCluster provides two ways to create shadow maps for a single light source. One light can affect self shadows in the volume differently from the shadow that is thrown onto other objects by the cloud or volume effect. Imagine how much render time you can save by using just a single light in a scene. PyroCluster effects can be rendered in atmospheric mode so that they interact with the objects and lighting in your 3D scene -- or, when the PyroCluster effect doesn't need this level of interaction, it can instead be rendered much more quickly as a 2D post effect and composited directly into your render. The variety of options provided help you to maximize the impact of your imagery as well as minimize your render times. Thick, turbulent volcanic clouds are just one of the PyroCluster presets. In the real world, explosions, clouds and smoke interact with the objects around them, and so can PyroCluster effects. PyroCluster's extensive options include control over the lighting and shadowing of particles. The effect can cast and receive shadows, as well as shadow itself. You can also activate illumination to brighten your scene with a flickering candle or a massive fireball. And if you're using CINEMA 4D's optional Advanced Render module, PyroCluster's volume and illumination are included in the radiosity calculation for even more realistic lighting solutions. Imagine what you could do with this amazing volumetric solution -- with PyroCluster the possibilities are literally endless. 8 REFERENCE PYROCLUSTER Creating a PyroCluster Effect To get you started as quickly as possible, here are the essential steps to produce a PyroCluster effect. Setting up a PyroCluster effect is a simple process of making two special new materials in the Material manager and then assigning those materials to the appropriate objects in the Object manager. - Choose Objects > Scene > Environment to create an Environment object. - In the Material manager, choose File > PyroCluster > PyroCluster - VolumeTracer to create a new Volume Tracer. - Drag the Volume Tracer from the Material manager and drop it onto the Environment object in the Object manager. The Volume Tracer can be assigned to any object and it will control the rendering of all PyroCluster effects encompassed by that object (see `Settings for the Volume Tracer Material' later in this chapter). Here we are assigning the Volume Tracer to an Environment object and you will often do that because the Environment object encompasses the entire scene. - In the Material manager, choose File > PyroCluster > PyroCluster to create a new PyroCluster shader. - Assign the PyroCluster shader to the relevant particle system (drag it from the Material manager and drop it onto the particle emitter in the Object manager). PyroCluster works best with a total particle count of around 200­600. To obtain a larger effect, instead of increasing the particle count you should increase the size of the puffs and make them more dense. You need high particle counts only for fast moving particle systems or when the particles disperse into a large volume. Assign just these two PyroCluster `materials' and you're up and running. Once the materials are assigned, creating the desired effect is achieved by adjusting various settings in the Material Editor or Attribute manager (see `Settings for the PyroCluster shader' later in this chapter). PYROCLUSTER REFERENCE 9 We have included many sample files and animations, and these can be found in the Features/PyroCluster folder within the CINEMA 4D folder. You might like to merge these into your own scenes and modify them to your needs. By experimenting with these sample effects you can begin to understand how to build your own effects from scratch. The settings for the Volume Tracer, which is the part of PyroCluster that controls how the effect will be rendered, can also be edited in the Attribute manager or Material Editor (see `Settings for the Volume Tracer' later in this chapter). With the settings for the PyroCluster shader and the Volume Tracer completed, you render a PyroCluster effect in the normal way, i.e. by selecting one of the regular CINEMA 4D render options. A PyroCluster effect can be rendered either as a full atmospheric effect or as a post effect according to the PyroCluster shader's Render Mode selected on the Globals page in the Attribute manager or Material Editor. How are PyroCluster effects created? Smoky effects require many complex fractal calculations to produce the `particles' that make up the volume. In the image above a single ray is illustrated cutting into a puff's volume, taking samples in order to produce realistic 3D volumetric effects. PyroCluster uses many of these rays to create the full 3D volume effect. As the rays travel deep into the puff's volume, a fractal calculation is made at every relevant point to produce the correct volume density. This is a number-intensive calculation and you can expect it to take some time; volumetric effects simply cannot be calculated quickly -- you might already know this if you've used volumetric lights. A faster processor will always speed up the rendering of PyroCluster's effects. Having said that, PyroCluster is built to be efficient and provides many powerful features to help reduce render time. There are many ways to fine-tune your scenes; one particularly useful one is found in the Volume Tracer settings. Changing just one setting here, World Step Size, can save hours or even days of rendering time. To obtain faster render times try increasing this value. For as long as there is no unacceptable degradation in image quality, keep increasing the World Step Size value. 10 REFERENCE PYROCLUSTER To find the optimum value for World Step Size we suggest using a manual subdivision technique. Start with a number as high as you think is reasonable, let's say 10. Perhaps the image looks terrible, with no detail at all. So cut the value in half and, if the image is still unacceptable, halve it again. When the image quality is acceptable, increase World Step Size by half the value that you previously cut it by -- so if a value of 5 produced a good image after 10, you would increase to 7.5. If the image is now poor again, decrease to, say, 6.3, and so on. With just a few test renders you will discover the optimum setting for the scene; you may find your scene now renders literally 100 times faster. No computer algorithm can do this job better than you can, especially as only you can decide when the image quality is acceptable. You can cut render times even further by gradually turning up the Ray Trans. Limit value once you have found the optimum World Step Size. PYROCLUSTER REFERENCE 11 Settings for the Volume Tracer Material The PyroCluster Volume Tracer is required for rendering the PyroCluster effects. Assign it to the object within which you want to use PyroCluster. The Volume Tracer is the part of PyroCluster that controls how the effect will be rendered and where it will be rendered. The settings you make for the Volume Tracer will greatly affect the render quality and render speed for the effect. There are no hard-and-fast rules for these settings, it will be different for every scene and will completely depend upon what is being rendered, so some experimentation will always be required to find the optimum settings for a Volume Tracer. See `How are PyroCluster effects created?' earlier in this chapter for further advice. The Volume Tracer is a special `material' and is created in a similar way to other materials in CINEMA 4D. To create a new Volume Tracer material: - In the Material manager, choose File > PyroCluster - VolumeTracer. Remember, to create PyroCluster effects you need to add at least two materials: VolumeTracer and PyroCluster. See `Creating a PyroCluster Effect' earlier in this chapter. You may have more than one Volume Tracer in a scene. Each Volume Tracer controls the rendering of all PyroCluster effects that are encompassed by the object to which the Volume Tracer has been assigned. Each Volume Tracer may have its own settings. You can edit the Volume Tracer's settings in the Attribute manager or in the Material Editor. Create a PyroCluster VolumeTracer `material' in the Material manager and select it to see its global settings in the Attribute manager. The Volume Tracer settings are `global' insofar that they affect the rendering of all PyroCluster puffs that are encompassed by the object to which the Volume Tracer is assigned. Render Objects, Render Hidden Objects To render PyroCluster effects in a scene, enable Render Objects. To render any hidden PyroCluster particle systems, enable the Render Hidden Objects option. 12 REFERENCE PYROCLUSTER Render Mode Here you can choose from various preset render modes. The main differences between these modes are their render quality and how long they take to render. In order of best render quality (and longest render time) first, these are: · Crispy · Crispy-Gas · Hazy The following mode: · User allows you to set your own render mode using various parameters that will no longer be ghosted including World Step Size and Ray Trans Limit. Step Size settings The Step Size settings are available only when Render Mode is set to User. See also `How are PyroCluster effects created?' earlier in this chapter. To improve rendering time for volumetric PyroCluster effects you should set the step sizes to reasonable values. What is a reasonable step size? This question leads us to a problem that is common to all volumetric fractals (a smoke cloud is a really large 3D fractal) ­ which is that you can never tell in advance exactly how they will look when rendered. Many parameters depend on each other and different combinations can have a dramatic impact on the look and the render time of the final effect. The step sizes control how accurately the 3D space is sliced to find PyroCluster volumes (puffs) in the scene. As a rule of thumb, lower values (more slices) will usually result in longer rendering times. If you feel that your scene is taking too long to render, try adjusting these values first. Suppose you've created a scene with some clouds in the sky. You have chosen really large volumes to create the 3D clouds (i.e. a large Radius value on the Shape page for the PyroCluster shader). Each single puff has a radius of 2000. If you leave the World Step Size at the default value of 0.5 you will wait forever to finish rendering the scene, as too many samples are taken over the large volume. In this case you could increase the step size values up to 60 without sacrificing the render quality. If, on the other hand, you choose a small Radius value, say 10, and you still use step sizes of 60 the render will be ugly, with single-color spheres only. This is because, with a step size of 60, nearly all the small PyroCluster volumes would be missed in the render. It will render very quickly, though!