Using the render cache will also provide you with a super fast initial preview of the scene so that you can evaluate the lighting setup quickly and cancel the rendering if the results are undesirable. The “render cache” option is used to provide a faster render time in conjunction with regathering. The “regather” choice next to the photon map option is also checked to ensure a realistic and smooth creation of shadows especially in corner areas. This provides an alternate method for light to bounce around in the scene and results in faster render times. The first of these options is the “global photon map”. These options have been chosen to speed the rendering process while preserving a realistic look. We will also be using several other options in the global illumination section. This will come from turning on global illumination in the luma server. With direct illumination turned off for the point light we will need to provide another way to illuminate the scene. This prevents the point light from illuminating objects by shining directly on them and results in a softer and more even lighting scenario. One of the changes made for the low preset is to turn off the direct illumination option for the point light in the luma server section of the options panel. This is due to the point light in our scene being used for direct illumination. You may have noticed that one of the differences between our two initial renderings is the bright spot on the floor when using the default options. Finding a balance between these values is crucial if you want quality renderings in a reasonable amount of time. Higher numbers for both the min and max sample amounts will result in a higher degree of detail and subsequently a longer render time. Image sampling controls the level of detail or resolution of the rendering produced. Let's discuss the options that were changed from the default settings when making the bzpreset file we just used. Keep in mind that once non-white materials are applied the decay option will likely make this scene too dark and will need to be turned off. The inverse square option should be selected as well to keep this white scene from getting too bright. Decay limits the ability of light to bounce around in the scene and thus makes the result more realistic in this case. The decay option is used here because everything in the scene has a white material applied to it by default.
Changing these focus values is one way to alter the brightness of the scene. The focus option gives our point light both a “hot spot” or brightest area and a “fall off” distance which controls the spread of the light. We won't be using “direct illumination” right away but it doesn't hurt to have the shadow option on in the meantime. Turning on shadows will cause any objects directly illuminated by our light to cast a shadow. Following the screen shots below, set your lights parameters to include Shadow, Focus and Decay. Then open the object properties dialog for the light by clicking the properties icon or typing the command “properties”. With the point light selected, position it just below the ceiling height somewhere in your scene. Brazil can use this regular Rhino point light but in addition will also enable it with a wide range of options specific to Brazil lights. Using the scene provided, add a point light to the model with the normal Rhino light tools. The first step in any interior rendering should be to add some light.
#Vray for rhino number of light bounces download#
You can also download this simple Rhino file to use with the presets provided.
To make things simple, here are three “.bzpreset” option files for you to use as you become familiar with the settings described. This tutorial will cover several techniques for lighting an interior scene in Rhino and will hopefully demystify the process of choosing photon map and light parameters. Brazil r/s offers a wide variety of control for how light and shadow are calculated in any given rendering.