Easily Render Models in Revit® from Other Software Libraries
This time we are sharing our Tips&Tricks article that was published in RevitCommunity some time ago. Hope it can be useful not only for RevitCommunity readers but for our blog followers too. So please read and benefit from advices on how to work smarter without using Revit plugins.
To get more realistic and high quality render requires a lot of time working on details. However we don’t always need to have exact details or spend time on them, therefore there are big model libraries on the internet for rendering purposes. Those might contain trees, grass, site elements, furniture, and so on.
Unfortunately those are usually not suitable for Autodesk® Revit® as they are mostly used by visualization professionals who use visualization software like 3ds Max, Cinema 4D, etc. However we can get quite good results using one of the suggested Revit rendering engines.
First, I would suggest you to begin with a separate Revit project for our rendering and then just link the main project into it. In that case, we won’t overload our main project with all detailed geometry that will be used only for rendering purposes.
Secondly, let’s find a model we want to add to our Revit project. There are various libraries on the internet with free or paid 3D models that can be used for visualizations. Here is a random bench, I found on some free library on the internet.
The main thing is to access layers of the 3D model. The easiest way to do so is to convert model to *.dwg format and open it in AutoCAD. Remember, when you export model to *.dwg all textures will be lost, thus only geometry and layers will stay. Anyway, materials from other software are incompatible with Revit rendering engines. You can use any other software that can work with layers of the model and export it to *.dwg (or *.dxf) format.
Let’s open the model in AutoCAD. The main goal is to have as many different layers as we would like to have different materials in the Revit model later. I’ve decided that in this my example I need to have two different materials to be applied on my model. Therefore, I will create two separate layers and change their color so that I could clearly see whether all geometry is applied to my created layers later on. The color of the layer won’t have any impact on the rendered view of the model in Revit.
Now I have to apply each part of geometry to desired layer. Sometimes all geometry can act like a single piece. In that case, we need to explode it (sometimes a few times), but be careful and do not explode it too many times because you can lose surfaces. Surfaces should stay. It is better when you have solids.
After I exploded my geometry and added it to different layers (in my case I added handles to Metal layer and planks to Wood layer), I have to make sure that all my solids (or surfaces) are of my created layers’ colors (in my case, after I added solids to the layer, they kept their former colors). If they are not, I have to either explode them once again or use Block Editor (in AutoCAD) to make sure, that color is applied to every geometry “By Layer”. This part is very important as materials will be applied by layer’s color later in Revit.
Now I’m sure that all my geometry is under my new created layers and color of geometry is set “By Layer”. Let’s save the model to *.dwg format.
Let’s get back to the Revit project that we would like to have our model in. Now I have to go to Insert Tab and use either Link CAD or Import CAD tool. It doesn’t matter which one I choose, unless I want to delete my *.dwg file, in which case I have to choose Import CAD tool. I can also import my model into family, then hide 3D model in a plan view and draw symbolic lines of my model, thus I will see a simplified plan view of my project. However, I wouldn’t offer to follow this workflow if you need 3D geometry only for rendering purposes. In some cases, when elements are already distributed in the project, we can use Edit Family tool, add *.dwg model to the family and load it back into the project, so that all the elements of that family will be overwritten with new 3D geometry and we won’t need to distribute every element by hand again.
Once the model is imported we have to make sure it is in scale. If it’s not, we can do it in Edit Type dialog of the imported element. Note that if you change only Import Units nothing will change. You have to adjust Scale Factor too (if units are correct, set Scale Factor to 1).
Now I should open Manage tab, choose Object Styles function and in Object Styles window go to Imported Objects tab. Here I should find my layers, previously created in AutoCAD, and assign materials to them.
This is it. If everything is done right and every geometry color is set “By Layer”, all that geometry should be rendered with my Revit materials.
You can add realistic trees, grass or other plants as well, and create really nice surrounding of your Revit project without using any professional rendering software. Just don’t forget to export or save to project your rendered images after rendering process is complete.