AECOsim Building Designer Quick Start Guide Chapter A17 Rendering 2012 Bentley Systems, Incorporated www.bentley.com/aecosim
Table of Contents Rendering...3 The Camera... 3 Materials... 5 Material Palettes... 5 Bentley_Materials.dgnlib... 5 Building_Materials.dgnlib... 5 Assign Material to Part... 6 Material Editor... 6 Lighting... 8 Brightness... 9 Ambient... 10 Flashbulb... 10 Solar... 10 Sky Dome... 12 Source Lighting... 14 Light Setups... 15 Environments... 16 Luxology... 17 www.bentley.com/aecosim Page 2 of 20 v2.0
RENDERING AECOsim Building Designer's advanced photo-realistic rendering provides tools to produce lifelike images of your models. Where the goal is to produce realistic images of the building model, the Luxology rendering engine can be used. This takes into account both direct and indirect lighting, such as reflection of light and refraction. Additionally, it can calculate diffuse reflections and caustics (such as reflected light, and refraction). THE CAMERA Setting up a view to be rendered is the first step in the rendering process. This can be done in a number of ways depending what feels most natural and intuitive to the designer. The Setup Camera tool, found on the Visualization task bar, is used to setup a view camera. The camera is setup in 3 point projection mode by entering data points to define first the view, then camera location, and then the camera target location. After selecting the view, use the Setup Camera dialog to select a lens, the Camera Height and the camera Target Height. Enter data points in any open view to define the camera location and the camera target. The active view updates to display the camera view. The Define Camera tool, found on the Visualization task bar, is used to manipulate a camera once it is placed. This can be done interactively by manipulating the dynamically displayed view cone via handles at strategic points. www.bentley.com/aecosim Page 3 of 20 v2.0
Alternatively, the Define Camera dialog can be used for specific manipulations and its settings window for precision inputs. Changing the camera Projection will adjust the number of vanishing points, determine whether the verticals remain vertical or vanish to a third point. To assist in visualizing the design as the camera is manipulated; turn on Continuous View Updates and Display View Cone The Walk tool, found on the Visualization task bar, is used to interactively walk through a 3D view. The key characteristic of the Walk operation is that the elevation (Z position) of the camera (eye point) generally does not change as it moves or turns. For example, if the camera is tilted upward or downward and the designer moves forward, the camera s elevation does not change. (The shift key in conjunction with mouse or arrow keys can be used to change the camera s elevation, if desired.) When the Camera Height setting is enabled, the camera maintains a specified height above the underlying elements, enabling the designer to walk up or down stairs, ramps, or slopes. The view cone, for the view being navigated, displays in all other open views. It shows the position and orientation of the camera in the view and can help with navigation. Please refer to the Help Document for a list of shortcut keys for the Walk tool. The Fly tool, found on the Visualization task bar, is used to interactively fly through a 3D view. The designer can navigate by using the mouse (with keyboard modifiers) or the keyboard. The view cone, for the view being navigated, displays in all other open views. It shows the position and orientation of the camera in the view and can help with navigation. Please refer to the Help Document for a list of shortcut keys for the Fly tool. www.bentley.com/aecosim Page 4 of 20 v2.0
MATERIALS In order to create photo-realistic images, the objects in the model need to have materials applied to them such that when rendered they take on the appearance of real-life objects rather than just the color of the design element. The part information that is applied to objects includes a material, therefore in AECOsim Building Designer the material is applied when the family and part information is applied. Material Palettes Material definitions are attributes related to color, texture, transparency, etc. and can include pattern and bump maps, as well as a host of other settings. Material definitions are created and stored in material palettes. Palettes can be stored locally in the DGN file, but more commonly one or more palettes are stored in DgnLibs and used as an external library. There are two material DgnLibs delivered with AECOsim Building Designer. Both offer a host of predefined material definitions for the novice or even expert renderer, but they are organized differently depending on the workflow of the user. Bentley_Materials.dgnlib The Bentley_Materails.dgnlib contains a series of palettes organized by material type, such as Glass & Plastic, Wood, Blocks & Bricks, etc. The delivered Building Dataset has parts that are mapped to this Bentley_Materials.dgnlib. In order to change a material assignment, the user would assign a different material to the part using the Assign Material to Part tool. This workflow requires that the user has write access to parts and a single dataset per project because changes to material assignments on the parts affect any building object that has that a part assignment. Building_Materials.dgnlib The Building_Materials.dgnlib (delivered in the \WorkSpace\Projects\BuildingExamples\BuildingSample_US\support\dataset\materials folder) contains a series of palettes organized by the Families in the delivered Building dataset. For every Part in the dataset there is a corresponding material definition. In order to change the appearance of a material, the material would be modified thru the Material Editor. In addition, the Building_Material.dgnlib makes use of Brick and Block Geometry Maps specifically drawn to match standard US brick and block sizes. This workflow does not require the user to have write access to the parts since the user is not expected to change the material assignment on the part. In addition, this DgnLib can be stored in the project dataset, allowing it to be stored in multiple project datasets, each with various material definitions for the same Family and Part. In this way the Building dataset can be shared by multiple projects, but each project can store its own material definitions. www.bentley.com/aecosim Page 5 of 20 v2.0
Assign Material to Part The Assign Material to Part utility is used to quickly assign material definitions to active parts and families. The Assign Material to Part tool is available from the Apply Material dialog box found on the Visualization Task bar, and the Query Material dialog box also found on the Visualization task bar. Please refer to the Help documentation for more information on the Assign Material and Query Material dialogs. The Assign Material to Part tool opens the Assign Material to Part dialog box. Select the Family and Part. Select the Palette and Material. Select Apply to make the changes to the Family and Part dataset. The Assign Material to Part dialog box can also be opened from the Material Editor dialog box. A menu opens when a right-click is issued on any material in the Tree view. The Assign to Part menu item opens the Assign Material to Part dialog box. In addition, palettes and materials can be assigned to Family and Parts in the Dataset Explorer by selecting the Rendering Properties tab. Material Editor The Define Materials tool is found on the Visualization task bar and will open the Material Editor which is used to create new materials and palettes or modify existing material definitions. www.bentley.com/aecosim Page 6 of 20 v2.0
Two modes are available in this dialog Basic Mode and Advanced Mode. Advanced Mode exposes more settings giving the designer more control over the material definition. www.bentley.com/aecosim Page 7 of 20 v2.0
The Preview section of the dialog includes a display of the material with the current settings applied. Hovering the cursor over any of the settings will create a pop up description of the setting and its effect on the material. In addition, each setting includes the ability to add an image file as a map to further define the setting, defining the Color as a pattern or the Surface as a bump, for instance. For more information on creating and editing materials see the Help documentation. LIGHTING Lighting is the key to photo-realistic rendering. The human eye first detects light versus dark in an image and then starts to fill in the details. If the lighting is wrong, then the brain recognizes this and is uncomfortable with this fact, even though the rest of the image is correct. So the time invested in setting up the lighting is well worth the effort. Below is a review of various lighting settings and their effect on the final rendering. The Light Manager tool, found on the Visualization Task bar, is used to control light setups and the settings for both global and source lighting. www.bentley.com/aecosim Page 8 of 20 v2.0
Brightness Display Brightness is used to interactively brighten or darken the image in the current display style. Global Illumination Brightness determines the method that will be used to adjust the global illumination brightness of a rendered solution. Brightness Multiplier scales all pixels by a specified factor. In the field, set the scale factor to be applied to the brightness of the pixels for the next rendering. Adapt to Brightness sets the brightness for the middle of the range. In the field, set the intensity (in lumens) that should be used as the middle of the display range for the next rendering. Drago tone mapping imitates the response of the human eye to light, with good preservation of details and contrast. Reinhard tone mapping works best with complete images where all pixels are lit; but it does not work well when you have many unlit background pixels. Gamma sets the display gamma level for the next rendering. The default gamma used to render is 1.7. Increasing the gamma value lightens the image, decreasing it darkens the image. www.bentley.com/aecosim Page 9 of 20 v2.0
Ambient Ambient lighting provides imaginary light to the scene that is presumed to strike every point on a surface with equal intensity. Increasing the intensity of the Ambient light will reduce the depth or contrast of the rendering, but it can be useful for lighting objects or surfaces that do not receive direct lighting. No shadows are cast by Ambient lighting. Ambient Lighting can be turned On or Off, and the intensity can be adjusted by changing the Lux. The Color and Temperature of the light can be set, as well. Flashbulb Flashbulb is a point light source originating from the eye-point of the camera. The Intensity, Color and Temperature can be set just as for the Ambient light source. No shadows are cast by Flashbulb lighting Solar Solar lighting simulates light from the Sun. Shadows can be enabled or disabled for Solar lighting. The Solar light source can also be turned On or Off and the Intensity adjusted on the Solar Properties tab. www.bentley.com/aecosim Page 10 of 20 v2.0
The Details tab is used to define characteristics of the sun. The Color Type can be User Defined or Physically Based meaning that the color of the Sun is computed based on factors such as its position in the sky, air quality, and cloudiness. Shadows can be disabled or enabled. If they are enabled the sharpness of the shadows is defined ranging from Sharp to Soft Very Fine. The finer the shadow the higher the number of samples required to calculate the shadow, increasing rendering time. Cloudiness determines the cloudiness of the sky which affects how much the solar light bounces off the sky. This also affects the sharpness and intensity of the shadows, as well as the color of the light. Air Quality determines the purity of the air which affects how much the solar light bounces in the air. This also affects the sharpness and intensity of the shadows, as well as the color of the light. www.bentley.com/aecosim Page 11 of 20 v2.0
See Sky Dome for an explanation of how the Cloudiness and Air Quality settings affect shadows and light color. Latitude, Longitude, North Direction, Date and Time can all be set on the Solar Position tab on the Solar Light setup. All of these determine the position of the sun and therefore the light and shadows on the model. For additional Solar settings to create unusual and dramatic lighting effects on the rendering see the Help Documentation. Sky Dome Sky Dome is a directional light coming from each direction of an imaginary sky hemisphere. The Sky Dome provides direct illumination; for indirect illumination, use an environment. This setting is used to add atmospheric lighting from the sky. If the Color Type is set to User Defined then the Color and Temperature buttons are used to define the color and temperature of the sky dome. If it is set to Physically Based it uses the Solar settings to determine color and temperature. When a Sky Dome is turned on with Solar lighting, the intensity of the light is modified by the angle of the Sun (providing a more realistic solar study). As cloudiness increases, the direct sunlight decreases but the amount of light from the sky increases. www.bentley.com/aecosim Page 12 of 20 v2.0
The amount of Cloudiness and the Air Quality is set to create the desired conditions. On a clear day, for example, the sky is not uniformly lit. More sky light comes from the direction of the Sun, thus producing darker, sharper shadows. Alternatively, on a cloudy day, the sky is uniformly lit with softer, less pronounced shadows. With Air Quality set to Perfectly Clean, there is a small amount of coloring from the sky lighting. When Air Quality is set to Industrial, the coloring effect of the sky lighting is more pronounced. Enabling shadows causes longer render times. 1- Rendered image without Sky Dome 2 - Rendered image with Sky Dome www.bentley.com/aecosim Page 13 of 20 v2.0
Source Lighting Unlike Global Lighting, which is controlled solely from the dialog, Source Lighting consists of light sources in the form of special cells that are placed in the model file. AECOsim Building Designer supports four source lighting types Directional, Point, Spot, and Area, which are delivered in the cell library lighting.cel. Light source cells are placed with the Place Light tool and have a number of settings that can be adjusted to get the correct lighting. For photorealistic rendering, use IES lighting files to set physically correct values for Point, Spot, and Area light source cells. The Place Light tool found on the Visualization task bar is used to place a Point Light, Spot Light, or Directional Light, light source cell, or to create an Area Light from existing elements. Select the light type icon from the top of the Place Light dialog. The light source cell appears, attached to the pointer. From the Preset option menu, choose a light. In the Name field, enter a name for the light. Change any additional settings as desired. Follow the prompts on the lower left of the interface to place and position the light cell in the model. Each of the available light sources is described below: Point Light Light is radiated in all directions from the origin of the light source. Spot Light Directional light having a conical beam, similar to a flashlight. Spot light sources having the same Lumens and Intensity settings as a Point light source may appear brighter in rendered images because the energy is restricted to the cone angle. Directional Light Directional light, producing parallel light rays throughout the model. That is, the light source's orientation defines the direction of uniform light that illuminates all surfaces facing in its direction. This applies whether they are in front of or behind the light source in the model. Area Light Useful for many diffuse lighting situations, such as simulating fluorescent lighting, where the light source is neither a Point light nor a Spot light. Area light sources are created from existing polygonal shapes in the design. www.bentley.com/aecosim Page 14 of 20 v2.0
During processing for rendering, the source lighting cells present in the active file always are considered. Any source lighting cells located in references, however, are ignored unless the Use Lights setting is turned on for the reference. This setting is turned on in the Attachment Settings dialog when the reference is attached. For previously attached references, toggle the Use Lights setting on or off via the Attachments Settings dialog. This dialog is opened by selecting Settings > Attachment in the References dialog. Light sources present in references that have Use Lights turned on, can be seen in the Light Name list of the Light Manager dialog. Lights from references are displayed in collapsible lists under the name of each reference. The settings of light source cells in references can be viewed, but they cannot be edited from the active file. IES lighting data files can be used to provide the most accurate lighting, but standard light source cells can be used as well, to provide the illumination. Both processes use the Lumens value, multiplied by the Bulbs value, to determine the brightness of the light source. Where lighting effects that match the expected physical lighting are required, it is recommended that IES lighting data files be used. Light Setups The settings for each of the various light sources can be saved as a Light Setup so that they can be recalled and reused again. The Light Setup List turns on or off the display of the light setups list, from which a saved lighting setup can be selected. When the list is not displayed, the down arrow will open a pull down list of the saved light setups. www.bentley.com/aecosim Page 15 of 20 v2.0
ENVIRONMENTS For an exterior rendering, or an interior rendering which has a view to the outside, it is important to define an environment. An environment is simply the surroundings around the building. The environment can provide a background, indirect light, reflections and refractions to the rendered image. The environment Maps dialog controls the environmental settings for Luxology rendering, as well as controls the visibility of these environment settings. The Environment Maps dialog opens by clicking the Environment Maps icon on the Visualization task bar. It can also be accessed from the Luxology Render dialog or by clicking the Environment Maps icon on the Materials toolbox. Luxology environments can be saved and recalled at render time. The environments are similar to render settings in that they can be stored in a DGN library file (DGNLib). The environment types are Sky, Light Probe, Image, Image Cube and Gradient. A number of preset environments are delivered with AECOsim Building Designer. www.bentley.com/aecosim Page 16 of 20 v2.0
All environments produce indirect light on the scene and are controlled by a brightness slider. To illuminate a model or scene solely by the enabled environment, choose the Override Existing Lights option. The Visibility check boxes determine where the environment is visible, for instance, if it is visible to the camera it will show up as the background. Alternatively, a Background can be enabled, and an image selected as the background, but the environment will still provide indirect lighting and be visible in the reflections and refractions of any reflective surfaces. For additional information on creating custom environments, see the Help Documentation. LUXOLOGY The Render icon found on the Visualization task bar is used to set up and preview the rendering. The dialog also provides tools to access the Material Editor, the Lighting Manager, the Environment Settings, and Rendering settings. The Begin Luxology Render (Alt+R) icon starts the Luxology rendering process to render a new solution of a selected view or, if a fence is present in the view, the fence contents. Once the preprocessing phase of the rendering is complete, the computation process continues independently, allowing other AECOsim Building Designer tools to be used in parallel with the rendering process. www.bentley.com/aecosim Page 17 of 20 v2.0
The Toggle Preview icon toggles the Fast Preview option On or Off. Fast Preview is a mode that quickly and interactively displays the results of changes to rendering, lighting, and material settings. This mode is invaluable for a variety of rendering tasks; everything from setting up the right camera view to tweaking materials to perfection. The Pull-Down opens the Fast Preview dialog, which is used to set options for a fast preview of the rendering The Luxology Render Settings (Alt+T) icon opens the Render Settings dialog. The Pull-Down opens a drop-down menu that contains predefined setups. The View icon opens a drop-down menu in order to select the view to be rendered. Any View from 1 8 can be selected. The X and Y Values to the right indicate the number of pixels for the rendering based on the View Size and the resolution set in the Luxology Render Preferences (Alt+F). If the lock icon is enabled then the aspect ratio of the image is locked to the aspect ratio of the view being rendered. The Save Image to File icon opens the Create Luxology File dialog, which will save the current Luxology rendering to an image file. Controls on this dialog are identical to those on the Save As dialog. The standard image formats are available as well as Radiance High Dynamic Range (HDR). The HDR format stores high-definition imagery that can be post processed in other applications. If the scene has been rendered using the Piranesi Rendering Setup, it can be saved as a Piranesi.epx file. Antialiasing should remain off (default) in this setting. Enabling antialiasing will produce undesirable artifacts. The Previous Luxology Render icon (Enabled only when a previous rendered image is available) and the Next Luxology Render icon (Enabled only when a latter rendered image is available) provide the ability to view the previously rendered images. Clicking the down-arrow opens a drop-down menu from which any previous history image may be selected to view. The Luxology Render Preferences dialog is used to set the number of history images stored (default 100). The Background icon is enabled only if an environment was not used as the background for the rendering. In these cases, the drop-down dialog can be used to change the background, without having to reprocess the rendering. The Background icon reflects the selection. www.bentley.com/aecosim Page 18 of 20 v2.0
When background is set to color or image, clicking the Background icon opens the Modify Color dialog or Open Image dialog as appropriate. Enabling the Lock, retains the same background setting for future rendering. The Update Active Environment with Current Background Settings icon is used to update the active environment with the current background settings. The Adjust Image Settings (Alt+I) icon opens the Luxology Image Settings dialog, which allows adjustments to the settings for the currently displayed rendering. Clicking the down arrow opens the same settings in a drop-down menu. The Overlay Visible Edges toggle is used to turn on or off the visible edges overlay. To enable this setting, it must first be turned on with the Render Visible Edges check box in the Render Settings dialog s Settings tab. Click the down arrow next to the icon to display options for changing the color of the Visible Edges and Hidden Edges. 3 - Rendered Image with Overlay Visible Edges enabled www.bentley.com/aecosim Page 19 of 20 v2.0
MOVIE: Rendering This movie shows: 1. Camera 2. Materials 3. Lighting 4. Environments www.bentley.com/aecosim Page 20 of 20 v2.0