With the introduction of the new Rapid RT rendering engine in AutoCAD 2016, the rendering environment and settings of the software have changed significantly. Although you can use the new Rapid RT as well as older mental ray rendering engines with AutoCAD 2016, Rapid RT will remain active by default.
The new rendering settings are simplified and have fewer tools and they are also capable of creating more realistic renderings with fewer tweaks to the drawing. You can see a complete comparison between new enhancements in rendering tools for AutoCAD 2016 and the previous version on this Autodesk knowledge network page.
For this article, I will use a sample architectural model of a house and will focus on rendering an interior scene. To begin our rendering process, we need to set up some views that can be recalled whenever they are required.
I have created an interior view using the camera and navigation wheel and have created a final rendering that looks like the image shown in Figure 1. In this article, I will explain how this result can be achieved with AutoCAD 2016.
Setting Scene and Light Settings for Rendering
Because this article is related to rendering in AutoCAD, I will not emphasize the details of making a drawing view, which you can easily create using the camera and navigation wheels. Once your view is set up, you can start by adding point lights to the ceiling light fixtures.
To add point lights, click on the Point option on the Create Light flyout of the Lights panel. Then click on one of the ceiling light fixtures and then copy this point light to other light fixtures as well. Once you have your lights in place, go to the Render panel and select the Low render preset from the Render Presets drop-down menu. This Low render preset will create a quick rendering, giving you a first-hand look at the quality of rendering that you will achieve with your current settings. When you are satisfied with the overall rendering quality, you can choose higher-quality presets like medium or high as well.
In AutoCAD 2016, some additional presets like Coffee-Break Quality, Lunch Quality and Overnight Quality have been added that will render your drawing for 10 minutes, 60 minutes and 12 hours, respectively, giving you a range of quality outputs.
Once you are satisfied with your rendering settings, click on the Render to Size button on the Render panel. A new rendering window will appear and you can see the progress of the current rendering in the progress bar at the bottom of the rendering window. When the rendering is finished, you can click on the Save button on the top-left corner of the rendering window to save the rendering as an image file in JPEG, PNG, TGA, BMP or TIF format.
Your first rendering may not look quite like an ideal realistic image and you may need to tweak light settings multiple times to get the best results. To adjust the brightness of point lights, close the Rendering window and click on the small arrow on the lower-right corner of the Lights panel on the Visualize tab. A new Lights in Model palette will appear that will list all of the lights included in the drawing.
Select lights by pressing and holding the CTRL or SHIFT key and then right-click on any one of the lights and select Properties from the contextual menu. From the Properties palette, select the Lamp Intensity field from the Photometric properties palette and increase or decrease this value to change the brightness in the scene. To increase the intensity of light, you can change the value of the Intensity factor from the General panel of the Properties palette as well.
Once you have chosen these settings, click on the Render to Size button again to see the results. You may need to make multiple adjustments to these light settings in order to achieve the best results.
Working Faster with Environment Presets
In AutoCAD 2016, there are many rendering presets that can be used as a ready-made template for your lighting and exposure settings. To set environment presets, go to the Render panel and expand it, then select the Render Environment and Exposure option. A new palette will pop up with a big environment button on the top. Click on this button to turn on Render Environment. Once the button is turned on, all palette options will become accessible. From the Image Based Lighting drop-down menu, select a preset. For this case, I selected rim highlights and I kept the other settings unchanged. Then I rendered the view and Figure 4 shows the final result that I achieved with the Low render preset in the Render panel.
As you can see, the final render is not that bad—the fine adjustments of exposure and brightness are already configured and it produces an average result. For better results, you can also select other environment and quality presets.
The Render Environment presets also come with 360-degree image-based backgrounds that can be used to create realistic backgrounds for your renderings. As an example, I have made a rendering of an exterior scene with a Low render preset and Plaza as background preset. Figure 5 shows the result that I achieved.
In this case, the castle-style building on right side of rendered image was not a part of the actual 3D model, but it was added with the Plaza environment preset. You can also orbit your drawing to see the background changing in real time, giving you a 360-degree view of it.
Using Custom Background
If you are not happy with the available background presets, then you can also add your own background using the Render Environment and Exposure palette. To add your own custom image, select the Use Custom Background radio button from the Render Environment and Exposure palette and click on the Background button next to it as shown in Figure 6.
An Image Based Lighting Background window will open and from this window you can select the image in the Type drop-down menu. Click on the Browse button in the Image options panel. Locate the image that you want to use as a background and then click on OK. In this case, I am selecting a sky background.
You may also need to adjust the image size so that it fits completely in the available background. To do that, click on the Adjust Image button on the Image options panel and select Stretch from the Image Positon drop-down menu of the Adjust Background Image window. When these settings are selected, click on OK to close all the open windows. Once again, click on the Render to Size button from the Render panel to see the results of adding the sky background to the drawing. Figure 7 shows the result I achieved after rendering with the Low render preset.
Creating High-Quality Renderings
To create high-quality renderings, you can change the render quality preset from the Render panel. You can select the Coffee-Break Quality or Lunch Quality presets to create high-quality renderings, but these presets will also increase the rendering time required. If you want an even higher quality of renderings, you can try the A360 Cloud Rendering as well, but this will require an Autodesk A360 cloud account and cloud credits.
The biggest advantage of rendering with a cloud account is the short rendering time and high-quality results. You can also get some additional environment presets and settings when you render your model online. With A360 Cloud Rendering, you can render single as well as multiple views simultaneously. To use the Cloud Rendering feature, log in with your Autodesk User ID in the software, save your drawing and click on the Render in Cloud button of the A360 panel. The drawing will upload to an Autodesk A360 cloud account where it is rendered.
Did you find these tips and tricks for the new and simplified AutoCAD rendering tools and settings useful? What are some new enhancements that you would like to see in upcoming AutoCAD versions? Don’t forget to let us know in comments below.