Lighting/shading > Batch Bake (mental ray)

Lighting/shading > Batch Bake (mental ray) >

Objects to Bake: Select from this list to bake all objects, or only selected objects.
Skip objects in initialBakeSets: If you select Select All from the Objects to Bake option, then all objects that are not assigned to the initial bake sets are baked.

For information about initial bake sets, see Assigning objects to bake sets.
Bake To: Bake either textures or vertices. The default is Texture when you access this window through the Lighting/Shading menu. If you select vertices, vertices are baked in the same manner as Bake vertices.
Bake Optimization: Select Multiple objects to bake in the default light map mode. This baking method is single threaded and uses one thread per object. This method can give better performance for baking multiple objects.

Select Single object to use lens shader baking. The shape of the lens changes to be the same as that of your geometry. This baking method is multi-threaded and uses multiple threads for each object. This method can give better performance for baking a single complex piece of geometry.

You can only use Bake Optimization when baking to textures.
Bake Shadows: Enable this option to bake shadows.
Camera: Select the desired view by specifying the corresponding camera name.
Keep Original Shading Network: Check this option to leave the current shading network intact.

If this option is unchecked, a file texture node will be created and attached to the object’s current shading network.

This option is only applicable if you bake to textures.

Regardless of whether this option is checked, a texture file is saved to disk.
Use Bake Set Override: Override the texture Bakeset attributes saved in the scene and use the following settings instead. When this option is checked, the Texture Bake Set Override/Vertices Bake Set Override options become active.

Texture Bake Set Override

Presets: This option allows you to save and reuse the settings you have entered for the attributes below.

Color Mode

Determines the baking mode for the scene. Select one of the following:

Light and Color: Bakes light and color information.
Only Light: Bakes only lighting information.
Only Global Illumination: Bakes only global illumination information
Occlusion: Bakes occlusion information.

Occlusion Rays: Determines the number of occlusion rays to trace per sample point. Increasing the number of occlusion rays improves quality, but reduces performance speed. The default is 64.
Occlusion Falloff: Determines the maximum length of an occlusion ray. Rays longer than this value are not considered for occlusion.

For texture bake sets, if Final Gather is not used, occlusion is computed for all sample points. Although this takes time, the result is very sharp light maps. If Final Gather is used, and the final gather quality is greater than 0, the occlusion is pre-baked into a final gather map. This final gather map can then be interpolated during rendering providing quick results at a reasonable quality.
Normal Direction: Use the Normal Direction drop-down list to set the direction of the baked object’s resulting normals. Select from Face Camera (towards the camera), Surface Front (outwards from the object surface), and Surface Back (inwards from the object surface).
Orthogonal Reflection: This option is on by default. When turned on, the Orthogonal Reflection option causes all reflection rays to be orthogonal to the surface being baked. They are no longer true reflection rays, pointing instead parallel to the surface normal vectors, but the resulting baked texture or vertex colors are meaningful when viewed later from any direction. This option should be turned on if the textures or vertex colors generated are to be used as textures in a game engine.

Turn this option off if you are baking in order to accelerate software rendering and the reflections are only viewed from the baked position. However, in this case, the textures or vertex colors generated are not for use as textures in a game engine.
Prefix: Any bitmaps generated by this bake set are prefixed with what is typed in this box. When Bake to One Map is checked, what you type in this box becomes the filename.
x resolution, y resolution: The horizontal and vertical resolution of the image file, measured in pixels. The slider range is 1 to 512. The default value is 256.
File format: Lets you choose a format in which to save the file texture. The default is TIFF.
Bits per channel: Specifies the number of bits per channel to use in the output bitmap.
Number of Samples: Use this option to specify the number of samples (per pixel) that is used for anti-aliasing during baking. The default value is 1, and the maximum value is 4.
Bake to One Map: Any objects assigned to this bake set are baked to the map. (Make sure the object’s UVs are not overlapped.)
Bake Alpha: Turn this on to bake the alpha channel (equivalent to Maya’s Bake Transparency option) and then select an Alpha Mode.

NoteWhen you turn Bake Alpha on, the transparency connection is automatically made for you when you add a surface shader.
Alpha mode: When Bake Alpha is turned on, the Alpha Mode specifies how it’s computed. Select one of the options, which include Pass Through (alpha as output from shading network) Surface Transparency, Luminance of Surface Color, and Coverage.

NoteThe Pass Through option is mainly for custom shader usage within Maya. The returned baked color alpha component is retained and is not further affected by Maya's matte channel. Custom shaders usually set the fourth component of a mental ray color to provide the alpha channel.
Final Gather Quality: Determines the final gather precompute quality. When rendering from the camera, mental ray precomputes a final gather pass before actually rendering the scene. This precomputation pass is disabled by default for baking.

When this attribute is set higher than zero, mental ray computes a number of final gather points before it bakes the lightmap. When this attribute is set to one, the resulting lightmap should be of approximately the same quality as a lightmap rendered from the camera. When this attribute is set higher than one, then the quality of the lightmap is improved as a denser map of final gather points is precomputed.

Do not use this option to tune final gather quality for baking. Final gather quality affects the number of points calculated at the precomputation phase of the final gather algorithm. By increasing the final gather quality, you are only creating more points during precomputation and possibly reducing the amount of interpolation or extrapolation required during rendering. Increasing the final gather quality does not affect the accuracy of the light calculated for each point or the filtering that is used on the data.

Instead, adjust the Scale in the Render Settings Window. This attribute controls the accuracy of the light calculated for each final gather point. Adjust also the View (Radii in Pixel Size). This attribute controls how data is interpolated/extrapolated between final gather points.
Final Gather Reflect: Determines the reflectivity of an object when precomputing final gather points for light mapping. This simplifies the simulation of reflective objects whose texture maps include contributions from objects that surround them. For example, if the Final Gather Reflect value is set to 0.25, every fourth final gather point is precomputed on the object hit by the reflection ray.
UV range: Specifies whether to bake the area in UV space from [0,0] to [1,1], bake the entire UV space, or bake a manually specified space range.
U min, U max: Slider values specify how much to stretch the sampling range of U or V components. Maya stretches the sample region to fit the output image size within the [0,0] to [1,1] sampling range.
V min, V max: Minimum V and maximum V for baking.
Fill texture seams: If the selected UV space contains boundaries, these boundaries may appear as black stripes in renderings that use the baked textures. This occurs when the texture is sampled so close to a boundary that the filter picks up values (generally black) from outside the desired space.

This setting artificially extends the boundaries by a small amount to alleviate this problem. It is measured in texels (pixels of texture). Typically, the filter is only a few texels in diameter and can only reach as far as its radius into these boundary spaces, so a value of 1 or 2 is usually enough.
Override mesh UV set assignments: Activate this option to bake meshes as if they were in the specified UV set instead of the UV sets to which they are currently associated.
UV set name: The UV set to use for the meshes in this textureBakeSet.

Vertices Bake Set Override

Presets: This option allows you to save and reuse the settings you have entered for the attributes below.

Color Mode

Determines the baking mode for the scene. Select one of the following:

Light and Color: Bakes light and color information.
Only Light: Bakes only lighting information.
Only Global Illumination: Bakes only global illumination information
Occlusion: Bakes occlusion information.

Occlusion Rays: Determines the number of occlusion rays to trace per sample point. Increasing the number of occlusion rays improves quality, but reduces performance speed. The default is 64.
Occlusion Falloff: Determines the maximum length of an occlusion ray. Rays longer than this value are not considered for occlusion.
Normal Direction: Use the Normal Direction drop-down list to set the direction of the baked object’s resulting normals. Select from Face Camera (towards the camera), Surface Front (outwards from the object surface), and Surface Back (inwards from the object surface).
Orthogonal Reflection: This option is on by default. When turned on, the Orthogonal Reflection option causes all reflection rays to be orthogonal to the surface being baked. They are no longer true reflection rays, pointing instead parallel to the surface normal vectors, but the resulting baked texture or vertex colors are meaningful when viewed later from any direction. This option should be turned on if the textures or vertex colors generated are to be used as textures in a game engine.

Turn this option off if you are baking in order to accelerate software rendering and the reflections are only viewed from the baked position. However, in this case, the textures or vertex colors generated are not for use as textures in a game engine.
Color Set Name: Use this option to indicate the color set that you want to bake to.
Bake Color: Turn this attribute off when you do not want to bake the color channel. When this option is on, you can set Min Color and Max Color values, and the Color Blending method. This attribute is on by default.
Bake Alpha: Turn this option on to bake the alpha channel (equivalent to Maya’s Bake Transparency option). When this option is turned on, you can set Min Alpha and Max Alpha values, and the Alpha Blending method. This attribute is off by default.
Scale Rgba: Scale vertex colors by the specified value.
Clamp Min, Clamp Max: Turn on these attributes to clamp the minimum and maximum color and alpha values so that the values are forced to be within the set range.
Min Alpha: The lower clamp limit for the alpha channel.
Max Alpha: The upper clamp limit for the alpha channel.
Min Color: The lower limit to which to clamp vertex color.
Max Color: The upper limit to which to clamp vertex colors.
Color Blending: Merges existing vertex colors with the ones just baked, if any. Select a merge method from the Color Blending drop-down list.
Alpha Blending: Merges existing vertex alphas with the ones just baked, if any. Select a merge method from the Alpha Blending drop-down list.

Vertex Color Filtering

Filter Size: If final gathering is baked to vertices and the scene contains high frequency information, discontinuities in the color channel may become visible. This artifact becomes especially apparent if low final gather quality settings are used. Filtering baked vertex colors yields the desired smooth look.

Provide a small positive filter size as argument to this parameter (it is multiplied by the object's bounding box size to obtain the absolute size). Set the Filter Size value to -1 to turn filtering off. Set the value to 0 or larger to turn it on.

Start with values in the 0.1 range as this value is multiplied by the object’s bounding box size to obtain the absolute size. This process also allows smaller values to be used for the Accuracy attribute in the Render Settings: mental ray tabs(Indirect Lighting tab > Final Gathering section) for faster performance although accuracy of results may need to be taken into account.

Lower final gather quality settings require larger filter sizes to get a smooth look and renders are less accurate. In general, the final gather quality should be raised as long as rendering times are acceptable; then the filter size should be increased until the desired smooth look is obtained. A tiny filter size may suffice; it enforces that baked colors are shared at vertices which have identical positions and normals.
Filter Normal Tolerance: The filter normal tolerance in degrees (0 to 180).

This lets you adjust the angular tolerance for smoothing value across faces.

Vertices whose angular separation is greater than the entered value are not taken into consideration for filtering so that crisp transitions are maintained across hard edges, and undesired color bleed doesn’t occur.

After adjusting this option, repeat the prelight operation to test. When a fairly smooth result is obtained, use the Filter Size to adjust further.
Use Face Normals: Use this option when you want to specify the use of face normals for baking instead of interpolated vertex normals (the default used for rendering). This option is off by default, and was previously found in the mental ray Baking Options (Batch Bake) dialog box.