ArtMatic Designer Concepts

Definitions

Precisely how the final output value is mapped to a color depends on the whether the tree is scalar or RGB-based. For RGB-based trees, the color is calculated directly from the 3 output values of the last Tree tile. If the tree is scalar or 2D (2 outputs), the color mapping is handled by the active Shading mode that uses the main gradient to provides the colors. In most cases low values will be mapped to the left-hand color of the gradient and higher values are mapped to the colors further right.
Even when the Tree is RGB and don't use the Main Gradient it can have components that uses it to shade the component results like 13 Main Gradient .

What is a gradient? A gradient is a special type of palette that has a user-definable number of color slots. Each slot has its own color. ArtMatic automatically generates all the colors that lie between adjacent slots by linear interpolation ; so, with a few mouse clicks you can create rich palettes. For example, if you want to create a palette that goes from black to white with all the shades in between, you only need a gradient with two slots. Select black as the left-hand color and white as the right-hand color, and ArtMatic does the rest. Each keyframe can have its own gradient. You can store your own gradients in ArtMatic's gradient library. You can also export and import gradient libraries using the Gradient Editor.
Click on any color box of the gradient to choose another color. With shift key down the change is stored into all keyframes. Use the Edit gradient below for structural changes and more editing options.

Global Input Matrix

The Global Input Matrix feeds information to the Structure Tree. In addition to the x and y canvas coordinates, time, audio analysis, and ArtMatic Voyager information can be sent to the tree. ArtMatic Voyager information is only sent to the tree when the ArtMatic structure is being used inside of ArtMatic Voyager. The other global inputs are generally used for one of two applications: 1) using time or audio input to influence the tree when rendering animation/movies, 2) using information from ArtMatic Voyager to create color maps influenced by elevation and/or slope.
The information passed out of global inputs (Z, W, A1, A2, A3, and A4) is determined by the Input Matrix mode. The x and y global inputs are always the (x,y) coordinates of the ArtMatic Canvas. The input matrix mode is set in the Input Matrix Setup dialog that is invoked by clicking on any label of the input matrix.

• Constant mode: Constant mode is the default mode of ArtMatic and is suited for 2D graphics and video applications.

  Z: relative time normalised (z flows from 0 to 1 during animation span, whatever its duration. This means that the speed of z will slow down when duration increases. Prior ArtMatic Engine 8.0.6 the z input was scaled by 4 ).
  W: absolute time in seconds.
  A1-A4: constant values;
  The Z input is time as a percentage of completion of keyframe animation. When keyframe animation plays, Z will be 0 when the animation starts and 1 (representing 100%) when the animation reaches completion. The W input, which is expressed in absolute time in seconds, is useful when you want some sort of change in the animation to be unaffected by the number of keyframes or the duration of the animation. For example, if you want the canvas to rotate at a rate independent of the animation's duration, use W. The constant values A1-A4 that can be set in the Input Matrix Setup dialog offers an alternate ways to send global values to component inputs. Unlike the 11, 12 or 13 constant components the input matrix constant can easily be used in the tree and within several level of Compiled Trees with the guaranty that the values will be the same for all sub-functions, thus acting like a global.

• Audio Input mode :
  Use this mode when you want to animate components with audio (either from audio file or live input) in Design or Explore room. Z & W: relative and absolute time;
  A1-A4: audio bands analysis information : A1 audio bass, A2 audio medium l, A3 audio medium h, A4 audio high.
  

  For the sound analysis to affect the Tree you will need to use values provided by inputs A1 to A4 to modulate tree parameters. See the examples provided in Libaries/Master Audio Input/ to learn various technics about how to make a Tree sound sensitive. The values in A1 through A4 represent the strength of the audio in the given frequency band. For example, connect a tile to A1 to have the bass frequencies influence the image. The audio can come from either live audio or an audio AIFF file. In audio input mode the following additional parameters are available: Input Device, Input Source, Audio Sensitivity, Sound In Inertia. The A1-A4 values are created by applying eight parallel DFT filters which are summed together in pairs. A1 is the sum of filters centered at 42 and 84 Hz. A2 is the sum of filters centered at 168 and 336 Hz. A3 is the sum of filters centered at 672 and 1344 Hz. A4 is the sum of filters centered at 7688 and 5376 Hz.
  ArtMatic Engine uses 44100 hertz for sampling rate and audio files needs to be in 44.1 to work properly. When connecting to an input device make sure the device is set to 44.1 (Sample Rate). Depth of input should not matter as its converted to float internally. On certain hardware monophonic input devices seems not to be supported.
  Audio Sensitivity is used to control how sensitive the system is to audio input. High values make the system more sensitive to audio. Sound In Inertia determines how smooth the transition between values is. When the inertia is low sudden changes in the audio can cause abrupt, jittery changes. Use inertia to smooth changes caused by the audio input.
  Animation playback will run forever in main ui and Full screen preview when using Audio Input mode with live audio. To start playback and sound input capture use space bar.
  
  
  TIP! When creating systems for audio control, you may find it useful to switch the Global Input mode to constant mode. While the dialog is open, you can change the constant values and observe how the system responds to the changes. This can give you an idea of what the A1 through A4 inputs do in the system without having to play audio.

• Time & Cycles:
  Time & Cycles mode is mostly used for sound design applications in the Listen room of ArtMatic Designer but can also be handy to control various looping features independently of keyframes. Z: absolute time in seconds. Note that z plays the role usually devoted to w input.
  W: integer counter (32 steps) with rate set in hertz
  A1-A4: free running oscillators (cycling values) set in hertz
  

  There is an additional parameter, BPM adjust, which adjusts the speed of all the oscillators at once - allowing them to all be sped up or slowed down. The W value is an integer value that cycles from 1 to 32 at a rate determined by the frequency (in Hz) parameter. A1 through A4 are the output of four independent saw-wave oscillators. For those unsure of what an oscillator is, A1 through A4 generate floating-point values that increase steadily from 0 to 1 as time progresses and then reset to 0 and start climbing again to 1. The oscillators repeat this over and over at a speed determined by the Saw Cycle setting in the Input Matrix setup dialog. The saw waves are especially useful for creating continuous rotation when connected to the third input of the 32 z Rotate component.

• ArtMatic Voyager:
  "ArtMatic Voyager" global input mode is used by ArtMatic files designed for 3D ArtMatic Voyager rendering. The mode provides various input information from Voyager context and rendering variables as explained below. Z: context dependent. When the ArtMatic Tree is 3D z will hold the third space coordinate.
  W: absolute time in seconds.
  A1-A2: Slope & Elevation;
  A3-A4: Image space view origin (x,y) or Image space sun position (x,y)
  

  This information is only passed in when the ArtMatic system is accessed from within ArtMatic Voyager. When an ArtMatic file is loaded into ArtMatic Voyager, it can receive various types of information from Voyager. This is covered in greater detail in the ArtMatic Voyager documentation. A1 and A2 are used to create complex color texture maps that allow color to be influenced by both elevation and slope.
  All values passed by Voyager through the X, Y and Z global inputs are scaled according to ArtMatic's view. The values passed through A2 are absolute and independent of the ArtMatic scale.
  Slope is only evaluated for color texture maps and at the color texture stage of combination mode planets. It has no meaning when the ArtMatic structure is being used as an elevation map.
  NOTE: Slope and elevation are only defined when the system is being used for the color texture/shading and cannot be used by those parts of a tree that define the elevation map (since slope and elevation only make sense after the elevation map has been calculated). In a tree that provides both color and the elevation map, the slope and Voyager elevation can only be used in that part of the tree that define the color.

• ArtMatic Voyager 3D Sky Dome:
  

  The input mode "Voyager 3D sky dome" is suited to visualize in 2D a 3D 360° Voyager Sky dome or to create 360° environment images in ArtMatic. A spherical inverse projection is used implicitly to view the Sky Dome. X Y and Z global inputs will return 3D coordinates on a sphere (with a 2:1 ratio). At default view size top and bottom line will map to north and south pole and coordinates will loop in X.
  Using 3D for the 360 environment has the advantage over 2D spherical mapping to have no deformation near the pole and can be viewed in spherical projection from any angle within Voyager.
  The component 3D SkyDome Planet makes creation of planets in 3D sky dome more easy.
  Except for the viewing geometry this mode is equivalent to the ArtMatic Voyager input mode. A number of 3D sky domes based trees are provided in the Environments 360 folder of the Voyager Library.

When Editing a Compiled Tree the Global inputs graphic make room for slots representing the CT's own inputs. They are labelled i1, i2, i3 and i4. You can actually remove one of these inputs if not used by (option click) on the input circle that corresponds. In some occasion you may want to connect a Tile inside the CT to global inputs bypassing the CT inputs. For example you may feed the CT with transformed coordinates while one element in the CT may need to use the original untransformed coordinates. In that case you will connect that tile to the global X Y inputs instead of i1 i2.

Auxiliary colors squares

The auxiliary color squares are color pickers for choosing the auxiliary colors used by some shading algorithms and various components. The number of auxiliary colors used is determined by the shading algorithm or the presence in the Tree of components using them. Note that auxiliary colors are global to a particular ArtMatic file and are not stored in keyframes so they can't be animated.

Depth cue color

The color used by Infinity, depth cuing when ON and certain Components like 44 Alpha Fade) or 23 Pict/Movie Overlay. The Depth cue color is always visible and available even if Depth Cuing is turned off. This color is used in RGB-based systems wherever the value infinity is encountered like the outside of pseudo 3D objects and where the infinity gate component is used.

Aux color A

Auxiliary color A (default : dark red) is used by several scalar tree procedural shaders (see below) and by RGB Multi mode mode for Tree extra outputs. A couple of components uses this color as well like 44 RGB * alpha or 13 Shaded plain color in certain modes.

Aux color B

Auxiliary color B (default : green) is used by several scalar tree procedural shaders by RGB Multi mode mode for Tree extra outputs. A couple of components uses this color as well like 44 RGB * alpha in certain modes. S:P Logic &Profiles uses Aux color B to shaded the edges for example.

• Cyclic clut:
  
  This shader causes the colors to cycle throughout the value range. It applies a sine function whose output value is mapped to the gradient. Zero is mapped to the gradient's central color. Clut stands for color lookup table.
  
  
• Ceiled Linear clut:
  
  This shader uses a linear scale to map incoming values to the gradient. 0 is mapped to the gradient's central color. The shader has a ceiling value above which the incoming values are mapped to the rightmost color. There is also a floor value. Values below the floor are mapped to the leftmost color.
  
  
• Logarithmic clut
  
  This shader is symmetrical about zero (i.e. -5 and +5 map to the same color) and the transition between becomes more gradual as the incoming values increase. Mathematically-speaking, the logarithm of the absolute value of the tree's output value is mapped to the gradient. 0 selects the leftmost color.
  
  
• Procedural A:
  
  Base shader: logarithmic color shader
  Auxiliary shading: pixel brightness determined by sine function
  Auxiliary colors: none
  This shader combines logarithmic and cyclic shading. The Logarithmic Clut algorithm determines the pixel hues. ArtMatic then imposes shadows by applying a sine function to vary the pixel brightness. Where the sine function is 0, the image is black and where the sine function is 1 the color is unchanged. The result is a sort of 3D cylindrical banding. To make the most of this shader, use a two input tile for either the final or the penultimate tile. Watch how the shading changes as you manipulate that tile's inputs.
  
  
• Procedural B
  
  Base shader: logarithmic color shader
  Aux.shading: aux. input 1 influences luminance, aux. input 2 determines color shift
  Auxiliary colors: Aux color B
  This shader uses two auxiliary inputs from the tree to modulate an image calculated using a logarithmic shading algorithm. The first auxiliary input provides luminance information and the second provides a color shift using the second auxiliary color. Note: the first auxiliary color is ignored by this shader.
  


• Procedural C:
  
  Base shader: logarithmic color shader
  Auxiliary shading: Auxiliary inputs one and two create a second image using a cyclic shader. Auxiliary input three controls the mix of the base and second image.
  Auxiliary colors: none.
  This algorithm calculates two intermediate images which are mixed together under the control of the third auxiliary input. The first intermediate image is calculated from the system using a logarithmic algorithm. The second intermediate image is calculated by feeding the first two auxiliary inputs into a sine-based shader. The third auxiliary input (from god knows where on the tree) controls the interpolation (mixing) of the two intermediate images.
  
  


• D:Log+Depth cueing+Color Filters:
  
  Base shader: logarithmic color shader
  Auxiliary shading: color filtering using aux. colors and inputs
  Auxiliary colors: Aux color A and B
  Global shading options: Depth Cueing
  This shader calculates a base image using logarithmic shading, turns on depth cueing (discussed later in this chapter) and uses the second and third auxiliary colors to filter the image. Two color filters (whose colors are provided by the second and third auxiliary colors) are calculated using two auxiliary values from the tree and applied to the base image. The filtering is done by multiplying the pixels of the filter with the pixels of the base image.
  
  
• E:Linear+Depth cueing+Lights:
  
  Base shader: logarithmic color shader
  Auxiliary shading: color filtering using aux. colors and inputs
  Auxiliary colors: Aux color A and B
  Shading options: Depth Cueing
  This shader is based on linear shading and operates similarly to shader D except that the auxiliary color images are combined with the base image using addition rather than multiplication. This shader also turns on depth cueing.
  
  
• F:Linear+Directional Lights:
  
  Base shader:linear color shader
  Auxiliary shading: directional lights controlled by the system's last vector function plus black shadows to emphasize lighting direction.
  Auxiliary colors: Aux color A and B
  This shader creates directional lighting effects. The last vector function (i.e. the last function with two outputs) of the Structure Tree provides direction information for directional lights used to shade the image. A primary white light is shined on the surface while lights of the three auxiliary colors are shined from different directions. Black shadows are provided which emphasize the lighting effect.
  
  
• G:Linear+3 Lights:
  
  Base shader:linear color shader
  Auxiliary shading:
  Auxiliary colors: Aux color A and B
  This shader is based on linear shading. Three pre-defined slots from the structure tree are used to provide lighting information using three auxiliary colors. The rules for determining which auxiliary inputs are used are complex. If there is a three-input component, its inputs are used to add the auxiliary colors. If there is no three-input component, the last three inputs on the tree are used. If the auxiliary colors are all black then the image will be identical to one shaded with the ceiled linear clut.
  Tip: To see how this shader works, use an all black gradient and note the effects of changing the auxiliary colors.
  


• H:Global Shade+3 Lights:
  
  Base shader:linear color shader
  Auxiliary shading: aux. inputs provide shading and lighting information
  Auxiliary colors: Aux color A and B
  Shading options: Global Shade On
  This is another complex shader based on linear shading. The Global Shade option--discussed later in this chapter--is turned on which uses an auxiliary input to control the luminance (brightness) of the image's pixels. The final component's output provides global illumination multiplied against the linear-shaded image. Three auxiliary colors provide additional lighting. Tip: For many structures, this can yield dramatic three-dimensional effects especially when the last component in the tree is the derivative (dx) function.
  
  
• I:Global Shade+Lights+Depth cueing:
  
  Base shader:linear color shader
  Auxiliary shading: aux. inputs
  Auxiliary colors: Aux color A and B
  Shading options: Depth cueing on
  This is another complex shader based on linear shading. It uses the last vector output function to provide depth cueing information and two other aux. inputs which control the application of auxiliary colors two and three.
  
  
• Linear clut (zero based) :
  
  This shader is essentially similar to the linear shader but maps zero to black and uses a normalised range so that 1 gets mapped to white.
  
  
• Balanced Log clut:
  
  Balanced Log performs logarithmic mapping of the gradient by using the gradient's colors for values greater than 0 and complementary colors of the gradient for values less than zero. This is a variant of the 'standard' Logarithmic Clut shader which uses the same colors for positive and negative values. This shader is especially useful when using ArtMatic to design sounds as it is very easy to see that positive and negative values are balanced (which is important for sound--since sounds that are out of balance suffer from DC Offset and will often result in clicks and distortion.
  


• Geographic clut
  
  Geographic Clut is a shader that aids artists designing DF fields or terrains for ArtMatic Voyager as this mode shows clearly the boundary between the inside and the outside (shaded with blue shades evoking underwater depth) of a DF volume or the elevations under sea level (at zero) for terrain modeling.
  ArtMatic Geographic Clut uses hard-coded colors to represent specific elevations. This mode is also available with RGBA trees.
  
  

• RGB Alpha (main out):
  
  RGB Alpha does no additional image processing. Most of the time, this is the shader that you will use when creating RGB-based graphics. When a tree has three outputs, they directly provides the Red, Green and Blue channels of the RGB image. If there is a fourth output its content is treated as an alpha channel that modulate opacity. A checkerboard pattern is used for transparent regions. If you don't want an alpha channel you can either :
  -use the mode RGB Multi mode
  -add a 33 tile to the end to convert to pure RGB (no alpha)
  -add a 44 tile "Alpha scale and offset" to zero the alpha scale and set the offset above 1 to ensure total opacity.
  NOTE: When rendering a movie with an alpha channel, make sure to select a codec compatible with alpha channels.
  
  
• RGB Density (main out)
  
  This shader is similar to RGB Alpha but turns any alpha value above zero to fully opaque. It is suited for DF color texturing when one need to preview the colors but still have a clue about the exterior of the object that will be fully transparent in this mode.
  
  
• Geographic clut (main out)
  
  Geographic clut creates a 3D topographic map where the fourth output of the tree provides elevation data and where the colors are provided by the built-in geographic clut. The first three outputs of the tree are ignored. So, it is often used while fine-tuning the system alpha or elevation output. Alpha channel/elevation values below zero will be shaded with blue shades evoking underwater depth. For DF modeling this mode shows clearly the boundary between the inside and the outside of a DF volume.
  In addition to elevation color mapping this shader uses the terrain derivative to bump-shade the surface for increased clarity. The 'Bump gain' tool described below controls the bump shading amount.
  This shader is more computationally-intensive since calculation of a system's derivative requires several Tree evaluation .
  
  
  
• RGBA Bump (main out):
  
  The tree's RGB output is lighted/textured using the derivative of the fourth output (bump shading). Negatives values will be shaded with bluish hues getting darker when the distance to zero increases. This shader provides a sense of how a four-output system will appear in ArtMatic Voyager when used as a colored terrain (where the first three outputs will be treated as color and the fourth as elevation). It is also suited for DF objects previsualisation as the exterior zones are below zero and the shades will give a sense of the Distance Field itelf.
  If the tree has only 3 outputs, a derivative calculated from a mix of RGB values.
  The 'Bump gain' tool described below controls the bump shading amount.
  This shader can also create dramatic 3D-like textures. While the Geographic Clut gives an accurate portrayal of the elevations created by the ArtMatic system, the Geographic Clut ignores the color information embedded in the ArtMatic system. The RGB+Alpha Bump shader gives you an idea of what the elevation map will look like when colored with the RGB information embedded in the system.
  This shader is more computationally-intensive since calculation of a system's derivative requires several Tree evaluation .
  
  
• RGBA Multi
  
  In this mode the alpha channel is ignored for the first output tile. Additional outputs will be composed to the overall image using the following rules :
  scalar (single out) values will be shaded in additive mode with Auxiliary colors coloring the output.
  RGB (3 outs) colors will be shaded in additive mode.
  RGBA (4 outs) values will be composited as alpha layer, that is the alpha value of the component will control the blending of the color.
  RGB multi is a fast way to compose several alpha layers over the first output that will be treated as an opaque background. It can also be used when the alpha channel is unwanted to render a RGBA system in opaque mode.
  
  
• RGBA Bump (multi out):
  
  This shader is similar to RGB Bump but can handle multiple RGBA outputs. It is particularly useful for dual shaded DF objects used in Voyager like :
  Opaque + Light
  Opaque + Transparent
  Opaque + Transmissive
  
  
  

• Default colors :
  uses a predefined particular palette for each algorithm. Default colors are usually related to the style or purpose of the texture.
• Main gradient :
  uses the Main gradient as the color palette.
• Indexed gradient :
  uses a given gradient as the gradient list. In that case parameter A (usually amplitude) becomes "Gradient index" and sets the index of the gradient.
• Color cycle :
  uses a palette created ad-hoc that cycle various hues with variation of luminances. In that case parameter A becomes "Color Cycle" and changes the hue and luminance of the palette. "Color Variance" parameter will spread the hues changes.


• use direct frequency :
  Frequency is used directly and this mode is suited for texturing inside ArtMatic.
• use Voyager km :
  Frequency is set in ArtMatic Voyager Km. This mode is suited for very large sizes in Voyager terrains design or low frequency textures.
• use 1/frequency :
  Frequency are set in 1/Frequency, thus larger values gives bigger sizes.
• Voyager DF mode :
  DF mode where amplitude is related to frequency (amp=1/f) but set in Voyager Km. Useful for large DF structures in ArtMatic Voyager.
• DF mode :
  DF mode where amplitude is related to frequency (amp=1/f). This mode is mandatory for DF 3D modeling.

• Infinity (DC color) : use Depth cue color for background default color
• Black : use a black background
• White : use a white background
• Aux color A : use Aux color A for background
  
• Aux color B : use Aux color B for background
  


• Scale height to Pi :
  Y maps to Pi (Legacy mode : In default view the entire height of the image fits the canvas).
• Scale width to Pi :
  X maps to Pi (In default view the entire width of the image fits the canvas)
• Scale height to 1 :
  Y maps to +-1 (In default view height of the image fits unit radius)
• Scale width to 1 :
  X maps to +-1 (In default view width of the image fits unit radius)

• direct value : parameter is left unchanged
• 1/value : The inverse of parameter value
• angle in ° When availabe this converts the parameter value from degree to radian
• exp(p*log(2)/4.) : When availabe value is set to exp(value*log(2)/4.). Exponentials are useful for animating scaling values in a natural way. Negatives input will enlarge scaling while 0 is identity and a value of 4 will yield 2.
• semitones : When availabe converts the parameter value to a semitones frequency ratio using exp(value*log(2)/12) which clearly returns 2 (the octave) when value is 12. The option 'semitones' is useful for sound synthesis. It sets the ratio in a temperated scale semitones.
  By scaling the input of a wave tuned to default you can transpose the pitch by semitones with zero being the fundamental, 2 one tone above, -3 a minor third below. A needs to be an integer to obtain a real semitone frequency. Of course the tuning will be relative to the fundamental frequency, so make sure it is set to a known value (Preferences dialog gives the tuning of a sine at frequency 1 in semitones where A0 is 441 hertz).
• value *10 : Uses parameter value time 10 to augment parameter range when needed.
• value /10 : Uses parameter value divided by 10 to augment precision.
• value /20 : When availabe uses value/20 to augment precision by 20.
• value *20 : When availabe uses value*20 to to augment parameter range.