This tutorial covers the baking process for a building facade.
Following this tutorial requires about 20-25 minutes, but once you have learned how to set up Total Baker's settings, it will take just a few clicks to create perfect bakes.
The high poly model used as example can be found under the folder
TotalBaker -> Models -> facade_high.fbx.
It has about 19k triangles subdivided into 5 meshes, each one with a different material.
Instead, the low poly model is located in
TotalBaker -> Models -> facade_low.fbx.
It has a single mesh with just 16 triangles and a material.
And this is the result we want to achieve with this tutorial:
First, open the total baker window by clicking on
Window -> Total Baker -> Open Total Baker.
We are now ready to start! Let's focus on the main input: the low poly model and the high poly model.
Drag the low poly model into the low poly object slot.
There's no need to smooth the model's normals, and the original model isn't smoothed, so set the "Normals" option is to "Import".
In the high poly object slot, drag or select the high poly model.
As before, set the Normals option to Import.
The next step is to make sure that the cage is set to Auto Generate Cage, and its offset to 0.02. In this way you force the system to generate the cage by creating an inflated copy of the low poly model.
Now, click on Update models in scene. Depending on how you've initially imported these two models, an alert dialog could show up. If so, just click on "Reimport" to automatically fix the import settings.
You can now see the models in your scene: the low poly model is on the left, the high poly model is on the right and the cage is wrapped around the high poly model.
Please notice that all the original scene’s objects have been put under a single inactive object named
Scene Objects and some new objects have been created.
Look at the cage object, which has a wireframe blue material. You can see that some of its faces are not connected. This is because the cage model (which derives from the low poly model) doesn't have normal smoothing, and its expansion causes the disconnection of the faces. Of course this is intentional, and allows to bake hard edges.
Now, open the "Output" panel, choose the output directory, a base name and set the resolution to 2048. Disable the Auto Update Preview option (you can always enable it later). When working with large textures the filtering operations may slow down the GUI interaction.
Now, let’s focus on the texture maps' settings by opening the Maps panel.
Here you can select which maps Total Baker has to bake (by checking the corresponding checkbox), and set some options for each one of them.
In this example, we want to bake Diffuse, Height, Normal, Metallic and Ambient Occlusion maps.
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Diffuse settings :
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Height settings :
Uncheck the 16 bits per channel option. This option is only useful when there's the need to save the height map in a 16 bits per channel format. Generally, you may want to save height maps in a 16bpc format when they have a lot of gradient areas and you plan to convert these maps into normal maps lately.
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Normal settings :
Choosing the right normal settings is a bit harder and requires the analysis of the high poly model. You may notice that almost all of its faces have the same normals. Baking these normals with a classic algorithm (Geometry or Interpolation modes) won’t produce a valid result. So, it’s necessary to build the normal map by height map conversion. To do so, choose the Height Map method for the Normals detection option.
Moreover, the material used for the bricks already uses a normal map. You can force Total Baker to add this map on the generated one by checking the Bake normal details option.
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Metallic settings :
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AO settings :
Set the AO algorithm to Classic. This is a raycast-based AO computation method which simulates how the light gets occluded in the real world.
Set the Occlusion Strength to 1, and the Max Spread to 0.1.
Then, set the Rays per point value to 30, which is quite performance killer, but also a good value in terms of quality.
Note : When using this method for your own bakes, I'd recommend to bake the AO mp separately from the other maps. This is an expensive algorithm, and it would be better to set a lower resolution and a lower rays per point to make some tests on the before baking the final hi-res map.
Now, click on the
button to start the baking process. This will take some time depending on the chosen resolution.
Once the process finishes, all the generated maps will appear in the preview area and the selected map’s filters will show up in the filters area. You can switch maps them using the buttons above the preview area.
The first result is good but not perfect.
First, change the low poly material’s rendering mode from Opaque to Transparent. This will fix the windows opacity while preserving their reflections.
And now, let’s apply some filters to the generated maps to improve the final effect.
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Diffuse
Set the dilation value to something > 5. This will prevent background bleeding.
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Height
Since we’re using the normals detection by conversion from height map, we can modify the height map parameters directly in the normal map’s filters panel. So let’s just go ahead.
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Normal
The normal map, as mentioned before, will be created by conversion from the height map, so it’s very important to filter the height map before filtering the normal map. Fortunately, while using the Height Map mode for normals detections, all the height map’s filtering parameters can also be modified in the normal’s filters area (highligthted in red in the image).
So, if you look at the low poly model, you will find it a bit flat. For this reason it’s necessary to blur the height map and higher its contrast to enlarge the slope areas (highlighted in yellow).
Some good parameters for this example are:
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Height Map Dilation: 20
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Height Map Blur: 10
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Height Map Brightness: -1.5
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Height Map Contrast: 5
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Invert Channels: No
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Bump Strength: 20
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Blur Large Details: 0
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Blur Small Details: 0
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Metallic
The metallic map doesn’t need filtering. Just set the Dilation to 0.
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AO
The AO map generally contains sharp shades, so it’s better to blur it a bit. Using a 3 pixels Blur will be fine. And don’t forget to dilate it (i.e. Dilation: 10) to avoid background bleeding!
Now that all the maps have been filtered, check the result in the scene. It should be something like this:
If you’re satisfied by this result, just clik on the
icon to save the baked textures in the previously selected folder.
Congratulations! This tutorial is completed.