modo bubbble logo

Image Baking Workflow


Home >> Shade, Light & Render >> Image Baking Workflow

back next
comment balloon Comments (4) RSS Icon
4.3/5 (1 vote)

Render baking is used to pre-compute texture and lighting information. The result is often used for real-time applications (such a for games) or for exporting models into other software packages with complex shading intact, or simply as a way to eliminate rendering overhead in elaborate scenes. In this way shaders and lighting are computed by the modo rendering engine and baked directly into an image that maps perfectly to an existing UV texture.

Perspective Projection
Hi-Res Geometry

 

Perspective Projection
Lo-Res Geometry

 

Perspective Projection
Lo-Res Baked Result

Depending on what your intended purpose is, there are a couple of methods for baking images. If your intent is to simply merge (flatten) multiple shader tree layers, then all that is needed is an image map added to the shader tree set to the appropriate 'Effect' type before baking. When baking maps such as Displacement and Normal maps, two layers of geometry are necessary, typically one is the high resolution model comprised of all the details of the final model, and a second low resolution model that approximates the shape of the high resolution model (and the baking target). The low resolution geometry requires a proper UV map with a unique name (unique from any materials applied to the high res version). Additionally, users will need to make sure the applicable layers are selected in the item list, and that the appropriate UV map is selected. When Baking to Textures, suitable image maps must be placed and selected in the Shader Tree (Don't worry, it only sounds complicated, each set-up is detailed below). For information regarding adding layers and setting their 'Effect', please reference the 'Shader Tree' page of the documentation. All of the baking commands can be invoked from the menu bar within the 'Render' menu. They are as follows-

Bake to Render Outputs--

The command 'Bake to Render Outputs' provides a means to render a texture layer utilizing the functionality of the Shader Tree's 'Render Outputs'. This allows the baking of Ambient Occlusion maps, or baking a Final Color output that computes all surfacing and shading of the final rendered item. Once rendered, images can be saved out from the Render Display viewport, then imported and applied to the geometry.
When invoked, the command will render into the currently selected UV texture map so it is important to make certain you have the correct mesh item layer and UV map selected prior to activating the bake operation. Render Baking will use the settings from the current 'Render Item' to determine quality and frame size settings as well as the intended contributors to the shading of the bake. By default, a baked render will contain all textures and shaders contributing to the RGB final image (as the default render output is set to Final Color). Baking can easily be redirected by simply retargeting the 'Effect' output setting on the Render Output prior to invoking the command.

 

Bake from Object to Render Outputs--

The 'Bake from Object to Render Outputs' command is similar to the 'Bake to Render Outputs' command above, however it allows the additional ability to render the surfacing and shading from a high resolution mesh onto a low resolution mesh. Baking from objects requires one high resolution model layer to extract the geometrical, shading and lighting information from and a low resolution proxy model layer with a UV map to apply those baked maps to. The low resolution layer should be in the foreground (selected and visible) while the high resolution model in the background (visible but unselected). In the Shader Tree, render baking will use the settings from the current 'Render Item' to determine quality and frame size settings as well as the intended contributors to the shading of the bake. Once specified, Bake from Object will proceed to use the low resolution layer's selected UV map to “Bake” out the user defined Image Maps. Once rendered, images can be saved out from the Render Display viewport, then imported and applied to the geometry.

 

Bake to Selected Texture--

The command 'Bake to Selected Texture' can be found in the menu bar under 'Render > Bake to Selected Texture', but is is more commonly invoked from the Shader Tree RMB context menu (opened by clicking on the target layer). This command offers the ability to generate a texture map image of one or more shader tree layers. Baking textures from inside the Shader Tree is useful for baking a single 'Effect' such as Diffuse Color into an image whereas the “Bake” command from the Render menu bakes all lighting, shadows and texture contributors into a final shaded image. It is reasonable to think of the Shader Tree level of baking as similar to flattening layers in Photoshop. Only layers of the same Effect setting underneath the texture layer that is triggering the bake will contribute to the baked layer. Once baked, this texture can remain in the Shader Tree as a pre-computed result of all contributors which results in a savings of render time and provides a real-time view of the effect within the viewport and when rendered. The 'Bake to Texture' command requires a UV map on the baked surface as well as a blank image map in the shader tree to bake into. Users should note that baked images are not automatically saved by modo. Once generated, images can be saved using the menu bar command 'File >Save Image'.

 

Bake from Object to Selected Texture--

This command offers the ability to use the UV map of a low resolution model to bake a texture map from a higher resolution model. Maps can be used for any of the various 'Effect' settings, including Diffuse Color, Displacement and Normal (This is how Tangent Space Normal Maps are created). Like the 'Bake to Selected Texture' command above, a UV map is required and a blank image map is necessary to bake into. Both surfaces must have different material name and cannot share the same UV map (meaning the name of each must be unique). When calculating a displacement map, the 'distance setting' from the popup requestor should be used as the 'Displacement Distance' setting in the Material dialog box when applied. Once baked, this texture can remain in the Shader Tree as a pre-computed result of all contributors which results in a savings of render time and provides a real-time view of the effect. Users should note that baked images are not automatically saved by modo. Once generated, images can be saved using the menu bar command 'File >Save Image'.

- You have to make sure that the normal Map layer in the Shader Tree is not in the same mask as the item you are trying to bake from

Tip icon

TIP: Depending on the type of geometry, and the resolution of the baked image, UV border seams may be visible. These can be eliminated by the using the 'Bake UV Border Size' option of the Preferences (menu bar 'System > Preferences', listed under Display > Rendering section). In order to take advantage of this functionality, users must have an active 'Alpha' render output as well, as modo uses the information of the alpha to compute the border offset.

 

comment balloon Comments (4) RSS Icon

Daniel Hruby January 11, 2011 at 9:24 PM

These video formats do not currently playback on the iPad.

MutantPixel January 12, 2011 at 9:04 AM

Yes, unfortunately, I just found that out myself. The iPad is very restrictive in its video support, I'll have to look into a solution down the line.

Dino Zanco June 5, 2012 at 3:52 AM

http://handbrake.fr/downloads.php (open-source, ipad presets)

MkIII May 12, 2011 at 4:12 AM

Bake from Object to Selected Texture does not work as shown for Color channels, either from the Shader Tree Right Click menu, or the Render Menu.

If you want to get Diffuse Color baked into your low res mesh, then you have to use a Diffuse Coefficient Render output, set up the Frame Size, Bake to Render Outputs, Save the render, reload the saved file.

Top

back next