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60_381304-ch46.qxp Part XI 7/7/08 2:18 PM Page 1116 Advanced Lighting and Rendering FIGURE 46.21 Placing the Glare map in the Output Camera Shader, you can get a strong glare from the light in the window. Using mental ray proxies Complex scene can have hundreds of objects and when rendered in mental ray, single frames can take several hours to render. This can make it tough to get previews to test lighting and atmospheric effects. If you know that the objects look fine, then you can use the mental ray proxy object to replace multiple objects or a single high-resolution object with a proxy. NEW FEATURE The mental ray Proxy feature is new to 3ds Max 2009. To use a mental ray proxy object, add a mr proxy object to the scene using the Create ➪ mental ray ➪ mr Proxy menu command. Select the Modify panel and click on the Source Object button, then select the object that you want to replace with the proxy. NOTE You can only select the source object in the Modify panel. When the source object is selected, you can save the object to a file. Source objects are saved as .mib files. The object is then displayed within the scene as a point cloud or as a bounding box and a preview of the source object is displayed in the Parameters rollout. You also can change the number of vertices that are displayed in the viewports. When the scene is rendered, the source object file is read in and used for the render. 1116 60_381304-ch46.qxp 7/7/08 2:18 PM Page 1117 Raytracing and mental ray Summary If you’re looking for a rendering option that perfectly calculates reflections, refractions, and transparencies, then raytracing is what you need. Raytracing settings can be set globally and applied to selected materials using materials and maps. And when raytracing needs an additional push, the mental ray renderer can be selected to render the scene. In this chapter, you accomplished the following:




Learned about the global raytracing settings Explored the raytrace material Worked with raytraced maps Learned to enable the mental ray renderer Created mental ray lights
Worked with caustics and photons
Used mental ray proxies Now that I’ve told you how to overload the rendering engine, the next chapter offers a way to get some help by batch rendering and rendering over the network. 1117 46 60_381304-ch46.qxp 7/7/08 2:18 PM Page 1118 61_381304-ch47.qxp 7/7/08 2:19 PM Page 1119 Batch and Network Rendering M ax can help you create some incredible images and animations, but that power comes at a significant price — time. Modeling scenes and animation sequences takes enough time on its own, but after you’re finished, you still have to wait for the rendering to take place, which for a final rendering at the highest detail settings can literally take days. Because the time rendering takes is directly proportional to the amount of processing power you have access to, Max lets you use network rendering to add more hardware to the equation and speed up those painfully slow jobs. This chapter shows you how to set up Max to distribute the rendering workload across an entire network of computers, helping you finish big rendering jobs in record time. IN THIS CHAPTER Setting up batch rendering Using network rendering Rendering on a network Using network rendering servers Logging errors Using the Monitor Event notification Batch Rendering Scenes If you work all day modeling, texturing, and animating sequences only to find that most of your day is shot waiting for a sequence to be rendered, then happily you have several solutions. You can get a second system and use it for rendering while you work on the first system, or you can use the network rendering feature to render over the network, or you have a third possibility: you can use the Batch Render tool. Unless you are working around the clock (which is common for many game productions), you can set up a batch rendering queue before you leave for the evening using the Batch Render tool. This queue runs through the night, giving you a set of takes to review in the morning. 1119 61_381304-ch47.qxp Part XI 7/7/08 2:19 PM Page 1120 Advanced Lighting and Rendering Using the Batch Render tool The Batch Render window, shown in Figure 47.1, is accessed from the Rendering menu. Render tasks can be added to the list by clicking the Add button. Render tasks can be disabled by selecting the check box to the left of the task name. FIGURE 47.1 The Batch Render window lets you define render tasks to be run as a batch process. For each task, you can set the task’s Name, Output Path, Camera, and render Preset. The Scene State dropdown list lets you select any scene states that are defined using the Tools ➪ Manage Scene States command. Each new task added to the Batch Render window uses the default render parameters for its frame range, dimensions, and pixel aspect, but if you enable the Override Preset option, then you can customize each of these parameters for the selected task. The Batch Render queue can be rendered over the network by enabling the Net Render option at the bottom of the Batch Render window. Managing scene states A single scene file may have many different settings that you’d like to try as different renderings. For example, you can set up a scene with different light settings, with different camera properties, or with unique materials. Scene states let you define different sets of properties that can be recalled prior to a batch rendering. Each of these scene states can be part of a single Max file. When the Tools ➪ Manage Scene States menu command is selected, the Manage Scene States dialog box appears, as shown in Figure 47.2, which lets you Save, Restore, Rename, and Delete the existing list of scene states. Clicking the Save button opens the Save Scene State dialog box, also shown in Figure 47.2. In the Save Scene State dialog box, you can enter the name for the scene state and select which group of settings to use. The options include Light Properties, Light Transforms, Object Properties, Camera Transforms, Camera Properties, Layer Properties, Layer Assignment, Materials, and Environment. 1120 61_381304-ch47.qxp 7/7/08 2:19 PM Page 1121 Batch and Network Rendering FIGURE 47.2 The Manage Scene States and Save Scene State dialog boxes let you define which properties to save as a state that can be recalled for a batch render task. Creating a standalone executable After a batch render queue is established, you can click the Export to .bat button to open the Batch Render Export to Batch File dialog box, where you can save the batch file as a .bat file. This saved file can be executed from the command line or by using an agent. Understanding Network Rendering When you use network rendering to render your animation, Max divides the work among several machines connected via a network, with each machine rendering some of the frames. The increase in speed depends on how many machines you can devote to rendering frames: Add just one computer, and you double the rate at which you can render. Add seven or eight machines, and instead of missing that important deadline by a week, you can get done early and take an extra day off. Machines connected to handle network rendering are often referred to collectively as a rendering farm. The basic process during a network rendering goes like this: One machine manages the entire process and distributes the work among all the computers in the farm. Each machine signals the managing computer when it is ready to work on another frame. The manager then sends or “farms out” a new frame, which gets worked on by a computer in the rendering farm, and the finished frame gets saved in whatever format you’ve chosen. The software in Max that makes network rendering possible is called Backburner. You may have noticed that it was installed when Max was installed. Max has several features to make the network rendering process easier. If one of the computers in your rendering farm crashes or loses its connection with the manager, the manager reclaims the frame that was assigned to the down computer and farms it out to a different machine. You can monitor the status of any rendering job you have running, and you can even have Max e-mail you when a job is complete. One additional caveat to using network rendering is that you have no guarantee that the frames of your animation will be rendered in order. Each participating computer renders frames as quickly as possible and saves them as separate files, so you cannot use network rendering to create .avi or .mov files. Instead, you have to render the scene with each frame saved as a separate bitmap file, and then use the RAM Player, Video Post, or a third-party program (such as Adobe Premiere) to combine them into an animation file format such as .avi. NOTE 1121 47 61_381304-ch47.qxp Part XI 7/7/08 2:19 PM Page 1122 Advanced Lighting and Rendering A licensed version of Max is required to do network rendering, but the good news is that only one machine in your farm needs to have an authorized copy of Max installed. No authorization whatsoever is needed on machines used for network rendering only. Simply install Max, and each network rendering machine gets its authorization from the computer that launched the render job. NOTE Setting up a Network Rendering System Before getting into the details of setting up Max for network rendering, it’s important to understand the different parts of the network rendering system. This list shows the major players involved:
Manager: The manager is a program (manager.exe) that acts as the network manager. It’s the network manager’s job to coordinate the efforts of all the other computers in your rendering farm. Only one machine on your network needs to be running the manager, and that same machine can also be used to render.
Server: A rendering server is any computer on your network used to render frames of your animation. When you run the server program (server.exe), it contacts the network manager and informs it that this particular computer is available to render. The server starts up Max when the manager sends a frame to be rendered.
3ds Max: At least one computer in your rendering farm must have an authorized copy of Max running, although it does not need to be the same computer that is running the manager. It is from this machine that you initiate a rendering job.
Monitor: The Monitor (monitor.exe) is a special program that lets you monitor your rendering farm. You can use it to check the current state of jobs that are running or that have been queued. You can also use it to schedule network rendering times. The Monitor is completely independent from the actual rendering process, so you can use it on one of the machines in your rendering farm, or you can use it to remotely check the status of things by connecting over the network. Starting the Network Rendering System Now that you know all the pieces involved, you’ll need to setup your network and install a copy of Max on all the network machines that you plan on using. When installing Max on a network machine, you can use the Compact option so that Max installs only the minimum number of files it needs to be able to render. You also need to choose a destination directory where you want Max to be installed. If possible, just accept the displayed default destination and click Next. Installing 3ds Max in the same directory on every computer can save you some maintenance headaches later on. Managing bitmap and plug-in directories is much easier if each machine has the same directory layout. TIP You also need to setup several shared directories on the network where the scenes and materials can be accessed from and where the rendered scenes can be saved. Once you have these shared folders in place, you are ready to start up your network rendering system. 1122 61_381304-ch47.qxp 7/7/08 2:19 PM Page 1123 Batch and Network Rendering Tutorial: Initializing the network rendering system The very first time you start your rendering farm, you need to help Max do a little initialization. To initialize the network rendering system, follow these steps: 1. Start the network manager on one machine in your rendering farm. This program, Manager.exe, is in the Backburner directory. You can start the manager by selecting it and pressing Enter in Windows Explorer. After it starts up, you first see the Backburner Manager General Properties dialog box. This dialog box appears only the first time you run the Manager.exe program or if you choose Edit ➪ General Settings. I cover its settings later in the chapter. After setting these properties, click OK, and the Manager window, shown in Figure 47.3, runs. FIGURE 47.3 Starting the network manager 2. Now start a network server on each computer that you plan to use for rendering. To do this, find and start the Server.exe program just like you did with Manager.exe. When you start this program for the first time, the Backburner Server General Properties dialog box appears. This dialog box is covered later in the chapter. Click OK, and the Network Server window appears, as shown in Figure 47.4. FIGURE 47.4 Starting a network server. Notice that the server is already looking for the manager. When the server finds the manager, it displays a message that the registration is accepted. The Network Manager window also shows a similar message. If the server had trouble connecting to the manager, you need to follow these two additional steps: 1. If automatic detection of the manager fails, the server keeps trying until it times out. If it times out, or if you just get tired of waiting, choose Edit ➪ General Settings to open the Backburner Server General Properties dialog box, shown in Figure 47.5. In this dialog box, uncheck the 1123 47 61_381304-ch47.qxp Part XI 7/7/08 2:19 PM Page 1124 Advanced Lighting and Rendering Automatic Search box and type in the name or IP address of the computer that is running the network manager. In this case, the server tried but couldn’t quite find the manager, so it had to be told that the manager was running on the computer whose IP address is 150.150.150.150. FIGURE 47.5 Manually choosing the manager’s IP address 2. Click OK to close the Backburner Server General Properties dialog box, and then click Close to shut down the server (doing so forces the server to save the changes you’ve made). Restart the server the same way you did before, and now the server and manager are able to find each other. NOTE The network manager does not need to have a computer all to itself, so you can also run a network server on the same computer and use it to participate in the rendering. Tutorial: Completing your first network rendering job Your rendering farm is up and running and just dying to render something, so let’s put those machines to work. To start a network rendering job, follow these steps: 1. Start Max, and create a simple animation scene. This should be as simple as possible because all you’re doing here is verifying that the rendering farm is functional. 2. In Max, choose Rendering ➪ Render (F10) to bring up the Render Setup dialog box. In the Time Output section of this dialog box, be sure that Range is selected so that you really do render multiple frames instead of the default single frame. 3. In the Render Output section of the Render Scene dialog box, click Files to open the Render Output File dialog box. In the Save In section, choose the output drive that can be accessed over the network and directory that you created in the “Configuring shared directories” section. 4. In the File name section of the Render Output File dialog box, type the name of the first frame. Max automatically numbers each frame for you. Choose a bitmap format from the Save as type list (remember, an animation format will not work). 5. Click Save to close the Render Output File dialog box. (Some file formats might ask you for additional information for your files; if so, just click OK to accept the default options.) Back in the Render Scene dialog box, Max displays the full path to the output directory. 6. In the Render Output section of the Render Scene dialog box, check the Net Render option, as shown in Figure 47.6. Change any other settings you want, such as selecting a viewport, and then click Render. 1124 61_381304-ch47.qxp 7/7/08 2:19 PM Page 1125 Batch and Network Rendering FIGURE 47.6 The Net Render option must be enabled to start a network rendering job. A Network Job Assignment dialog box opens, like the one shown in Figure 47.7. FIGURE 47.7 Use the Network Job Assignment dialog box to locate the manager to handle the rendering job. 1125 47