In AutoCAD renderings, many objects like vehicles and trees can be added to give it a more realistic appearance using a material created with opacity maps. To make these objects we need to create a material with image and it’s equivalent opacity map which if rendered in a 3D drawing will create the illusion of a realistic 3D object in the drawing.
Opacity map is a greyscale image in which black part is completely transparent and white is opaque and different levels of gray in the image decides the amount of transparency of the image.
In this article, I will explain the method of making a 3D realistic tree for our rendering.
Making a Tree material
For our example, I am using the image of the tree and it’s opacity map as shown in the image below. You can easily create opacity map from an image using photo editor tools like Photoshop. You can download the tree image with its opacity map and sample drawing used in this article from this link.
Open Rendering DRG drawing file and switch to AutoCAD 3D modeling workspace. Go to Visualize tab and click on Materials Browser icon to open it alternatively, you can also use its command equivalent MAT.
Click on the New material button on the lower left corner of materials browser palette as shown in the image below and select New Generic Material from the menu.
A new Materials Editor palette will pop up, enter the name of this new material, I am naming it as New Tree. From this palette expand the Generic group and double click on the box next to the image option.
Locate the tree image and click on Open. Double click on the image again to open the Texture Editor palette. Expand the scale group from the Texture Editor palette and change sample size in width and height to 12 units.
Expand Repeat group as well in the texture editor palette and select None from Horizontal as well as Vertical drop down menu. Once you have made all of these changes close Texture Editor palette.
Again go to Materials Editor palette and click on the Cutouts group, a new file browser will appear. Locate tree opacity map image and click Open to load it in the material.
Now double click on the image in the Cutouts group and change its scale to 12 units in Width and Height fields and also from Repeat group change Horizontal and Vertical values to None.
Applying Tree material to drawing
After making all of these changes close all open palettes except Materials Browser. Make a surface in drawing with length and height equal to 12 units.
Drag and drop New Tree material on the surface created in the previous step and your material will be applied to it. Change the visual style to Realistic from Visual Styles panel of Visualize tab.
Your drawing is now ready for rendering, click the Render to Size icon on the Render panel of Visualize tab and wait for the rendering to complete. The rendering which I obtained with settings mentioned in this article is shown below. I have used a background in the drawing to make the tree and its shadow more prominent.
If steps mentioned in the article are not clear to you then you can watch this video as well for the tip.
Do you have questions related to this tip? Let me know in the comments below.