We did an overview of SpeedTree last week, I wanted to show you what I was able to do from that point to create my own trees/plants. Using my own Leaf scans. First off, I wanted to run some tests in applications for generating Normals maps using my color map image. There are a bunch of ways to create normals now from images. I used the color map of a leaf from a SpeedTree plant so I could have it’s Normal map to compare from the versions I got in other applications. I started with this Leaf from a topiary vines tree I purchased called Kudzu.
SpeedTree Color Map:
SpeedTree Normal Map:
Newer version of Photoshop has ability to generate a Normal map from Filters–3d–Create Normal Map.
There a few parameters that you can tweak in this popup.
Here is the Normal map I got out of Photoshop
It’s not bad. I’ve found another application called “CrazyBump”. It’s a free beta software for Mac and PCs. It’s pretty good and straight forward to use. You can also output displacements, specular, occlusion, and diffuse passes.
You select “Open photograph from file”.
CrazyBump gives you more parameters to dial in your normal map.
Here’s the CrazyBump Normal
Last Application you can also use is by Quixel called NDO. It is only available for PCs and is not free. It has a lot of editing modes and parameters to use as well. I’m not versed in it yet but there are things that I like within it. NDO and rest of Quixel suite works within Photoshop as a plugin. You have full control of creating your normals here. There is also modes for creating and exporting other maps like CrazyBump does.
NDO Normal Map
I’ll hook up these maps in Maya and you can see the differences (if any). Here are the results compared to SpeedTree. Some small variation between them all. They all work, but if I’d have to pick CrazyBump is the closest to match the SpeedTree normal. Plus, CrazyBump is free and it has more settings than Photoshop. NDO is a good choice but since it’s not free and it has a lot more bells and whistles for simple normals it might be overkill. Click below to see full size.
This technique for creating Normals from images isn’t just for SpeedTree. This is great for texturing in general. You can pull out additional details from your color maps into your new normal map without having to add too much additional geometry to your object. Here’s a simple card with a texture I put on it quickly.
Now see a render with just the color map and then with the normal created from the color map.
Even though it’s not perfect and I only spent like a minute on this it give the impression of more depth to the geometry of the card.