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Image Map

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Image Map Texture Item

The 'Image Map' item could be considered the most important texture layer as it allows users to apply bitmap images to surfaces in MODO. When originating from a photographic source, bitmaps are a means of literally getting the richness of the real world into MODO, producing effects that would be difficult, if not impossible to produce otherwise. Want a surface to look like asphalt or dirt? Take a photograph and apply it as an Image Map; photographic textures are essential to photo real rendering.

Images created in editing/painting and illustration/typographic programs are extremely useful as well; label, posters, and other signage are great examples of this application. Image maps shouldn't be strictly limited to representing textured surfaces either, as they are also useful in many other cases; they can represent multiple complex procedural layers baked together, reducing the calculation overhead. They can be displacement maps created by MODO or other packages that apply high frequency details to lower resolution subdivision surface models, providing a better level of interactivity to items among other benefits. Volumes could literally be written about the utility of image maps (and they have been!). Searching the internet for tutorials on 'Texture Mapping' will uncover untold numbers of websites dedicated to this very topic.

Adding the Image Map can be done through menu bar command 'Texture > Add Shader Tree Layer > Image Map' or using the 'Add Layer' function at the top of the full 'Shader Tree' viewport. The Image Map item contains all the attributes directly related to MODO's usage of the bitmap and are available in the 'Properties' viewport when the item layer is selected in the Shader Tree. Scale, Position, Projection and other mapping specific settings are available in the associated 'Texture Locator'.

Image Map PanelLayer--

Enable: Toggles the effect of the layer on and off, duplicating the functionality of toggling visibility in the Shader Tree. When un-checked (disabled), the layer has no effect on the shading of the scene. However, disabled layers are saved with the scene and are persistent across MODO sessions.

Invert: Inverts the RGB values for the layer producing a negative effect.

Blend Mode: Affects blending between different layers of the same effect type, allowing user the ability to stack several layers for different effects. For more on blending, please reference the 'Blend Modes' page of the documentation.

Opacity: Changes the transparency of the current layer. Reducing this values will increasingly reveal lower layers in the shader tree if present, or dim the effect of the layer itself on the surface.

Locator: Most texture layers also have an associated 'Texture Locator' that is automatically created in the 'Item List'. This defines the mapping of the texture (way the texture is applied) to the surface. The 'Locator' option sets that association. Users can choose alternate locators, however, the need to do so will be very rare; still, there are some possible instances where users may want multiple texture items to share a single locator.

Image Map--

Image: This pop-up allows you to select or load the specific image to be applied. Additionally, there are options for creating new blank images which can be useful for painting, sculpting and image baking.

Antialiasing: This check box toggles the 'Antialiasing' function for the selected image layer, a means of filtering the texture to produce smoother rendered results. Antialiasing samples the images pixels in texture space (as opposed to screen or render space) and averages them based on spot size and strength. When 'enabled', the 'AntiAliasing Strength' and 'Minimum Spot' options become available.

Antialiasing Strength: Active only when Antialiasing is enabled, this setting allows you to control the amount of antialiasing on the image. Setting this value above 100% will create a blurring effect that smooths the texture image.

Minimum Spot: Let's start by saying you probably don't need to adjust this value. The default of 1 means that the spot size is accurate to the sub pixel level. Increasing the minimum spot size is mostly useful for blurring an image or reducing details when using an image for an environment map. Now to explain what it actually does.

The "Spot" size relates to the spot created on the surface of a mesh when intersected by a ray. Rays are actually conical; think of the beam of light from a flashlight. The further the ray's origin is from the surface that it intersects the larger the spot will be. Further, if the ray hits the surface at an glancing angle it can be even larger. When there is an image applied to the surface in question the render engine needs to know how many 2D texture pixels should be sampled within that spot. This becomes more important the closer the camera is to the surface. If the minimum spot value is 1 or smaller the spot size is not clamped and will accurately sample the texture image at the sub pixel level if necessary. When the spot size is set to a value of 2 or higher the number of pixels sampled will always be greater than 1. This will result in a slight blurring of the image.

Texture Filtering: When spot size is set to 1 and the camera is so close to a surface that it samples the image at the sub-pixel level (i.e. an image pixel is bigger than a rendered pixel), Texture filtering will average across those samples. The result is a smooth interpolation of pixels rather than seeing sharp angular pixel boundaries. Users can choose from several options--
Nearest-- Disables filtering of image, actual pixel of image will be sampled.
Bilinear-- Samples neighboring pixels vertically and horizontally, producing smooth (some might say slightly blurry) results.
Bicubic-- Samples all adjacent pixels providing the smoothest result.

Low/High Value: The Low/High values provide a means for users to re-map the total range of tones in an image, especially useful controlling value setting. For instance, if you are using an image as a displacement map you might want the darkest pixels to push the surface in and the bright pixels to push them out. By default the pixels of an image go from 0 to 100% which means that none of the pixels would yield a value to push the pixels inward. By setting the value range from -100% to 100% the image is effectively remapped so that the black pixels create a negative displacement and the white pixels a positive displacement with mid-tones being "neutral". Also could be useful in extending the range of standard (low dynamic range) images, making it possible to use standard non-HDR images to light a scene (although the results won't look as good as using a real HDRI)
Low Value-- Determines the effective value of pixels that have a true value of 0,0,0 (r,g,b)
High Value-- Determines the effective value of pixels that have a true value of 255,255,255 (r,g,b)

Invert Red, Green, Blue: These three check boxes allow users to invert any of the three color channels of an image map individually. While users won't likely use this option often, especially on color images, it can be helpful to save normal maps where certain channels are mapped differently (inverted?) to what MODO expects them to be.

Gamma: The 'Gamma' setting can be used as an image adjustment control to lighten or darken the image without the need to externally adjust it in an external bitmap editor. The Gamma adjustment is non-linear and will affect the mid-tones of the image greater than the shadow and highlight areas of the image. For best results, users should leave the Gamma value at the default 1.0.

Alpha Channel: This popup allows users to choose how MODO will handle alpha channel data (if present) contained in the image file.
Use Alpha-- Masks the color pixels based on the embedded alpha channel data.
Ignore-- Discards the embedded Alpha channel.
Alpha Only-- Ignores any RGB information in the file treating it strictly as an single (alpha) channel image.


UV--Iamge Still Panel

UDIM: The UDIM value is a notation that designates an offset to a specific UV tile location. It is designed to allow users to assign many textures to a surface at once. For more information on using and working with UDIM textures, please reference the 'UDIM Workflow' page of the documentation.

Set UDIM from Filename: LMB+clicking this button will cause MODO to read the filename for the selected texture layer(s) and automatically set the above UDIM value based on the filename.


Use Alpha: In certain game asset workflows, an embedded Alpha channel on an image map might represent an effect other than the images transparency. When set as such, it makes it difficult to view the image in the 3D viewports. In these cases the 'Use Alpha' option is a global way to disable any embedded Alpha channels from an image, allowing its color components to still be visible.

Colorspace: The 'Colorspace' setting defines the color space of the associated image layer, which controls how modo interprets the colors of the image itself for rendering. The settings for the Colorspace option can have a dramatic effect over how the colors look in the final rendered image, so setting it properly is important. For more information on a color managed worflow in MODO, please reference the 'Color Management' page of the documentation.





Image Sequence

Image SequenceAdditional options appear when users apply an Image Sequence as a texture layer. To access these options, select the 'Image Sequence' item, then select the 'Image Sequence' subtab from the Shader Tree properties panel.

First/Last Frame: The 'First Frame' and 'Last Frame' options determine the range from the sequence to display/render in MODO. Frames outside of this range will be ignored/truncated.

FPS Multiplier: This value determines the speed at which the sequence plays in relation to the FPS rendered in the MODO scene allowing users to adjust the timing of frames. So a 30fps image sequence applied to a 30fps would play at 1:1 frames when the value is 1.0 (One sequence frame for every rendered frame). A 2.0 value would be twice as fast as the scene, effectively skipping every other frame, conversely a 0.5 value would play back half as fast doubling the frames. Note that this speed affects the 'Start Frame' value below. A 'Start Frame' of 48 would actually start at 24 when the speed was 2.0.

Start Frame: The 'Start Frame' value determines the first rendered frame in MODO in which to begin the playback of the image sequence allowing users to delay the start of the sequence. Frames rendered prior to this value would hold the 'First Frame' as specified above essentially duplicating the 'First Frame' in subsequent rendered frames until reaching the 'Start Frame' value.

End Behavior: These options determine how MODO handles the image sequence when the 'Last Frame' value is reached-
Hold- Duplicates the 'Last Frame' on all subsequent rendered frames.
Repeat- Loops the sequence between the 'First' and 'Last Frame' values.
Mirror- Ping-Pongs the sequence forwards and backwards between the 'First' and 'Last Frame' values.

Tip icon

TIP: MODO will automatically use the first available or last available frame when corresponding frames don't exist in the specified sequence. Take, for example, a sequence from frame 45 to 100 applied as a background plate. If the 'First' and 'Last Frame' values are 1 and 100 respectively, and the Start Frame value is 0, when rendering out the sequence, frame 45 would be duplicated across rendered frames 1-44 as no frames existed in the specified sequence - essentially the same behavior as the 'First /Last option. Interim missing frames will be duplicated until a proper sequence frame is encountered.



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