Main Controls Rollout

Available in Krakatoa v1.0.0 and higher

Presets, Help, Navigation and Rollout Management Buttons

• The <||> button in the upper left corner provides local rollout Presets saving and Loading as well as access to the global Presets and History loading and saving.
• The Open Online Help button opens the default Web Browser and displays the page you are reading right now.
• Clicking or right-clicking the History button will close the Main Controls rollout and expand the Presets and History rollout.
• Clicking or right-clicking the Channels button will close the Main Controls rollout and expand the Channels rollout.
• Clicking or right-clicking the Particles button will close the Main Controls rollout and expand the Scene Particle Systems rollout.
• Clicking or right-clicking the Loaders button will close the Main Controls rollout and expand the Particle Loaders rollout.
• Clicking or right-clicking the Preferences button will close the Main Controls rollout and expand the Preferences rollout.
  • In all these cases, you can use the Back To Main Controls button in the corresponding rollouts to return to the Main Controls rollout.
• The []> button in the upper right corner provides quick access to rollout management functions:
  • Left-clicking the button will float the rollout as an independent dialog.
  • Shift+Left-clicking the button will dock the rollout in the Secondary floater, or if it is already there or floated, it will dock into the Primary floater.
  • Ctrl+Left-clicking the button will hide the rollout. You can use the Krakatoa:ManageGUIRollout|Manage Krakatoa GUI Rollouts]] rollout to unhide it again.
  • Right-clicking the button will open a context menu with all Floating and Docking options described above.

Lighting and Shading group of controls

>Ignore Scene Lights

• When unchecked, particles will be illuminated by the lights in the scene.
• When checked, all scene lights will be considered turned off.
  • Particles will NOT be illuminated at all, resulting typically in black particles.
  • If the >Use Emission option is enabled and the particles have valid Emission Channel data (provided by either the Self-Illumination property of a Standard Material, the Emission property of a Krakatoa Material, a local or global Magma Modifier with Emission Output, or the Emission Global Shading Channel Override), the particles will render as self-illuminated.
• Default scene lighting will NOT be taken into account when no scene lights are present or >Use Scene Lights is turned off!

Render Mode

• This drop-down list defines the method to be used to render the particles into the final image.
• The color indicator in front of the list is supposed to provide a sub-conscious hint of the current state of the feature.
• The list provides two entries:
  • Particle Rendering (white) - this is the original rendering mode of Krakatoa 1.1.x - every particle will be rendered as a pixel-sized point.
  • Voxel Rendering (blue) - this is the new rendering mode introduced in Krakatoa 1.5.0 - every particle will be encoded onto a voxel grid and the grid will be shaded.

Voxel Size

• This spinner controls globally the resolution of the voxel grid.
• It will be enabled only in Voxel Rendering mode.
• The value is in world space units and defaults to 0.5.
• The [>>] options button can be used to load, save and edit typical values as presets.

Voxel Filter Radius

• This spinner controls the number of neighbor voxels to filter over when shading a voxel.
• It will be enabled only in Voxel Rendering mode.
• Default of 1 means no filtering.
• Higher values produce fuzzier results at cost of render time.
• The [>>] options button can be used to load, save and edit typical values as presets.

Phase Functions

• The second drop-down list defines the phase function used to calculate the light scattering behavior of particles.
• The color indicator in front of the list is supposed to provide a sub-conscious hint of the current state of the feature
• The list provides the following options:
  • Isotropic (white) - light will be scattered uniformly in all ditections
  • Phong Surface (blue) - light will be scattered according to the Phong Shading model based on the particle’s Normal channel.
  • Henyey-Greenstein (orange) - light will be scattered according to the angle between the light and the camera and the Eccentricity channel or Phase Eccentricity global value.
  • Schlick (green) - light will be scattered according to the angle between the light and the camera and the Eccentricity channel or Phase Eccentricity global value.

>Force Additive Mode

• This special override forces Additive rendering by overwriting certain particle channels under the hood.
• Additive rendering requires the Scatter (Color) Channel and the Absorption Channel to be set to black and the Emission Channel to be set to the particle color - the result is particles that accumulate additively since they don’t scatter or absorb any light.
  • This can be achieved by setting the Color, Emission and Absorption channels manually using either the Global Overrides or KCMs.
  • The >Force Additive Mode shortcut performs the necessary operations internally, producing Additive shading with less steps.
• The following operations will be performed internally when this option is checked:
  • The Color Channel will be copied into the Emission Channel.
  • The Color and Absorption channels will be set to black.
  • The >Use Emission and >Use Absorption channels will be grayed out to denote the fact Krakatoa is controlling them automatically.

>Use Absorption

• The Absorption Channel controls the amount of light a particle will absorb.
• When unchecked (default), the Absorption channel will not be allocated nor used by the renderer. The Absorption of all particles will be assumed 1,1,1 (white) which will be then modulated by the density to absorb light equally from all three color components. This will produce gray shadows as in Krakatoa 1.1.x.
• When checked, the Absorption channel will be allocated and used by the renderer, allowing for non-uniform absorption of the three color components producing color shadows, or no absorption at all when set to black.
• Each particle can provide its own absorption value for non-isotropic behavior within a particle cloud’s volume.
• The content of the Absorption channel could be provided by one of the following sources:
  • Krakatoa Material - Absorption color picker or map
  • Standard Material - Filter color or map, subtracted from white (Filter is the inverse of Absorption)
  • Krakatoa Channels Modifier (KCM) applied to a PRT Loader or PRT Volume.
  • A Magma Modifier applied to a Global Channel Override Set affecting all particles from any sources.
  • Global Shading Channel Absorption Override color or map overwriting the Absorption channel of all particles form any sources.

Lighting Pass Filtering and Density | Final Pass Filtering and Density

• The Density Controls specify how Krakatoa computes the density of particles and how it draws points in Particle mode.
• There are two sets of density controls - Lighting Pass Density and Final Pass Density:
• The Lighting Pass performs the calculation of attenuation maps used for particle shadowing.
• The Final Pass draws the particles or voxels into the frame buffer.
• By default, both the Lighting and the Final Pass will use the Final Pass’ Density settings.
• When the >Use option is checked, the Lighting Pass Density controls will become available for separate adjustment.

Self-Shadow Filter

• The Self-Shadow Filter determines how particle self-shadowing attenuation is evaluated from the attenuation buffer in Particle Mode.
  • Nearest: The value of the nearest neighboring pixel is used.
  • Bilinear: Uses a simple linear equation to reconstruct the value from the nearest four pixels. In Krakatoa MX 2.0.0 and higher, an additional Filter Size value is available to the right of the drop-down list. When set to 1, the nearest 4 pixels will be used. When increased, more pixels will be covered. See here for details.
  • Bicubic: Uses a cubic filtering function to average the value of the nearby pixels.

Draw Point Filter

The Draw Point Filter determines how particles are rendered in Particle Mode when they fall partially into more than one integral pixel in the image plane. Nearest: The full value of the particle is placed into the nearest pixel of the output image. Bilinear: Uses a simple linear equation to split the value of the particle into the affected pixels of the output image. In Krakatoa MX 2.0.0 and higher, an additional Filter Size value is available to the right of the drop-down list. When set to 1, the nearest 4 pixels will be used. When increased, more pixels will be covered. See here for details. Bicubic: Uses a cubic filtering function to average the value of the particle into surrounding pixels of the output image.

For more details, see Filter Modes sub-topic on the Particle Rendering page.

Final Pass Density

• One of two settings required to define the rendered density of each particle.
• This value is the coefficient of the density as expressed in scientific notation.
• Smaller values make the particles appear less dense, while larger values increase the rendered density.

Density Exponent (10^x)

• The second of two settings required to define the rendered density of each particle.
• This value is the exponent of the power of 10, where the density is expressed in scientific notation.
• This provides a quick way to make large density adjustments.

To easily define very large or very small densities, the Particle Density value in Krakatoa is expressed in scientific notation which uses a numeric coefficient multiplied by an exponential power of 10. For example: The value 0.000005 can be expressed as 5.0 x 10^-6, or in Krakatoa terms, Density Per Particle: 5.0, Density Exponent: -6 The value 27500000 can be expressed as 2.75 x 10^7 or in Krakatoa terms, Density Per Particle: 2.75, Density Exponent: 7

Density Presets

Two [>>] preset buttons are located to the right of the two density spinner pairs. You can either click or right-click the buttons to get an existing preset Density and Exponent into the spinners, add the current values to the Presets list or, if the current values are already on the list, remove them from the Presets.

Emission And Reflections

>Use Emission

• The Emission Channel represents light emitted by the particle itself as opposed to light emitted by dedicated scene lights.
• When unchecked (default), the Emission channel will not be allocated nor used by the renderer. The Emission of all particles will be assumed 0,0,0 (black)
• When checked, the Emission channel will be allocated and used by the renderer.
• The content of the Emission channel could be provided by one of the following sources:
  • Krakatoa Material - Emission color picker or map
  • Standard Material - Self-Illumination color, map or value.
  • Krakatoa Channels Modifier (KCM) applied to a PRT Loader or PRT Volume.
  • Magma Modifier applied to a Global Channel Override Set affecting all particles from any sources.
  • Global Shading Channel Emission Override color or map overwriting the Emission channel of all particles form any sources.

Emission Strength controls

• The Emission Strength value was introduced in v1.6.0 to allow the independent control over the Emission decoupled from the Density channel.
• In prior versions, the Density channel affected the Emission, so for example trying to reduce the volumetric Density of FumeFX Smoke caused the Emission generated from the Fire channel to also become affected.
• By default the Emission Strength controls are disabled.
• To enable the controls, check the >Use checkbutton next to them.
  • Similar to the Density controls, the Emission Strength value is defined using two spinners - a coefficient and an exponent.
  • Changing the Exponent allows for quick orders of magnitude adjustments, for example changing a value expressed as 1.0/-1 to 1.0/-3 changes the resulting Emission Strength from 0.1 to 0.001 very fast without the need to enter multiple zeros.
• To set the Emission Strength value in relation to the Final Pass Density value, check the >Rel. checkbutton .
  • Setting the Emission Strength resulting relative value to 1.0 will use the same value as the Final Pass Density.
  • Setting it to 0.1 will set the Emission Strength to 1/10th of the Final Pass Densioty value and so on.

>Use Environment Reflections

• When checked, if the particles provide a valid Normals channel and there is a valid Environment Map in the 3ds Max Environment Map slot, each particle will look up the texel along the Normal in that map and use it as additional lighting pass, resulting in an environment reflection.

>Allocate ReflectionStrength

• When checked, a ReflectionStrength channel will be allocated in memory
  • It will be initialized to the Reflection Strength value specified in the Main Controls rollout (see below)
  • It can be specified per-particle via Magma modifiers or can be stored in cached PRT files.
  • It will be used to modulate the reflection strength per particle.
• When unchecked, no memory channel will be allocated and all particles will use the global Reflection Strength value described below:

Reflection Strength controls

• The Reflection Strength value was introduced in v2.0.0 to allow the fine-turning of the Environment Reflection Maps intensity without the need to adjust the bitmap loader as in previous versions.
• The value defaults to 1.0 which means regular intensity.
• A value of 0.0 makes the reflection invisible
• Values between 0.0 and 1.0 will gradually reveal the reflection.
• Values above 1.0 will boost the reflection beyond its regular value.
• Values below 0.0 will invert the reflection.

Motion Blur and Depth of Field

Adjust settings in this section to set up Motion Blur and Depth of Field in Krakatoa renderings.

>Enable Motion Blur

• This option enables the native Krakatoa Motion Blur calculation.
• NOTE that 3ds Max MultiPass Motion Blur is also supported but not recommended.
  • It will be much slower than the Krakatoa version since it has to load the particles N times - once for each pass.
  • If you want to match the Max look exactly though, you can use it.
  • Make sure Krakatoa’s >Use Motion Blur option is turned off when using it to avoid double-blurring the particles.

>Jittered Motion Blur

• When enabled, the Jittered Motion Blur option makes motion blur samples less uniform.
  • By default, when this option is disabled, the particle samples are placed at equal distances along the motion vector.
  • When Jittered Motion Blur is enabled, the particle samples will be shifted randomly along the motion vector to create a less uniform pattern.

>Sub-Sample Geometry

• In versions prior to v1.6.0 this option was called >Deformation Motion Blur.
• When checked, the geometry of Matte Objects will be reevaluated / recaptured on sub-samples to produce motion blur effects from geometry deformations (vertex animation).
• When unchecked, the geometry of Matte Objects will be evaluated only once and only Position/Rotation/Scale object-level animation will be taken into account.

Particle Segments

• This value determines the number of samples taken to produce the motion blur for the frame.
  • For example, a value of 10 will cause Krakatoa to render 10 samples that are in turn combined to produce a single motion-blurred frame.
• Increasing the number of samples creates a smoother motion blur at the expense of rendering time.
• The render time increase is linear, so if a frame takes 10 seconds to draw particles (pure drawing time excluding the time spent processing/loading/lighting them), then 5 passes motion blur will take approx. 50 seconds, 12 passes approx. 2 minutes etc.
• The value’s range is from 1 to 1000. The value of 1 was introduced in v1.1.0 since it can provide a single dot/random position rendering in conjunction with Jittered Motion Blur which might be desirable in special cases. When the >Enable Motion Blur checkbutton is unchecked, Krakatoa renders internally with a Segment count of 0.
• Typical values are provided by default in the [>>] presets list.

Motion Blur Shutter (deg)

• Using motion-picture camera terminology, this is a measurement in degrees representing the length of time the camera shutter is open.
• Larger values cause more blur as the camera’s shutter remains open longer and captures a longer time interval.
• Default is 180 degrees which corresponds to 0.5 in 3ds Max Multi-Pass Motion Blur terminology.
• 360 degrees corresponds to the default (but incorrect) 3ds Max Multi-Pass Motion Blur duration of 1.0 frame.
• 0 degrees practically disables Motion Blur.
• Using the [>>] button next to the Motion Blur Shutter value, you can access predefined Shutter values as well as add new presets or remove existing presets.

Matte Segments

• This value will be used when the >Use checkbox next to it is pressed.
• It controls the number of sub-frame samples to calculate when evaluating Matte Objects geometry.
• This control affects both transformation interpolation and, when >Sub-Sample Geometry is checked, the reevaluation of the geometry due to deformation modifiers and vertex animation.
• When the Matte Segments value is less than the Particle Segments value, the Matte Objects will be updated less frequently and their transformations and geometry will be interpolated where needed - this can be a significant time saver when the the modifier stack is very complex and takes minutes to update once.

Matte Objects Motion Blur Bias

• By default, Motion blur of Matte Objects is rendered with equal blur before and after the object’s position in the current frame.
  • Values less than 0.0 will cause more samples to be taken prior to the current frame
  • Values greater than 0.0 will cause more samples to be taken after the current frame.
  • Value Range is from -1.0 to 1.0. Default is 0.0 (centered).
  • This option is used to match the Motion Blur behavior of other renderers to allow composing Krakatoa Particles with matte geometry into scenes using Motion Blurred Geometry with non-zero Bias.
  • Currently, particles use Motion Blur with a bias of 0.0 (centered) regardless of this value. Particle Motion Blur Bias might be implemented in future versions of Krakatoa.
  • Using the [>>] button next to the Matte Objects Motion Blur Bias value, you can access predefined Shutter values as well as add new presets or remove existing presets.

>Adaptive Motion Blur

• Introduced in Krakatoa MX 2.6.1.
• When unchecked (default), the number of motion blur particle segments (passes) will be set to the same value on all frames by the Particle Segments control described above.
• When checked, the number of motion blur particle segments will be set automatically based on the fastest particle motion in screen space and the controls described below:

Min. Segments

• Available when the >Adaptive Motion Blur checkbutton is checked.
• Defines the minimum number of motion blur passes (particle segments) to be rendered.
• If the adaptive calculations have determined that a lower number of segments is required, the caclulated value will be clamped to this value.
• The minimum allowed value is 1, which corresponds to no motion.
• Default is 2.

Max. Segments

• Available when the >Adaptive Motion Blur checkbutton is checked.
• Defines the maximum number of motion blur passes (particle segments) to be rendered.
• If the adaptive calculations have determined that a higher number of segments is required, the caclulated value will be clamped to this value.
• Default is 64.

Smoothness

• Available when the >Adaptive Motion Blur checkbutton is checked.
• Used as a multiplier of the calculated screen space pixels the fastest particle will cover on the current frame.
• Default is 1.0.
• This value can be set higher than 1.0 to improve the quality of Jittered motion blur, or to a lower value than 1.0 to produce faster previews while still using adaptive per-frame particle segment numbers.
• The resulting value will still be clamped between the Min. and Max. Segments values described above.

Smoothness Bias

• Available when the >Adaptive Motion Blur checkbutton is checked.
• Used as an Exponent to bend the otherwise linear relationship between the number of screen shape pixels covered by the fastest moving particle. and the number of particle segments.
  • The particle segments value is first taken from the number of screen space pixels the fastest particle will cover on the current frame.
  • This value is then multiplied by the Smoothness value, and the result is clamped between the Min. and Max. Segments values.
  • The resulting value is then normalized to the range from 0.0 to 1.0 between the Min. and Max. Segments values.
  • The normalized value is then raised to the power of Smoothness Bias, and the result is then rescaled to the range between the Min. and Max. Segments values.
• Default is 1.0, which results in linear relationship between screen pixels and particle segments.
• Values higher than 1.0 will produce less particle segments than the number of screen pixels, for example if 32 passes were expected in a range from 1 to 64, with a Smoothness Bias of 2.0 only 16 passes will be rendered.
• Values lower than 1.0 will produce more particle segments than the number of screen pixels, in the above example 45 passes would be rendered instead.

>Disable Blur From Camera Motion

• When unchecked (default), Camera motion will generate motion blur in addition to any particle motion.
• When checked, only particle motion will generate motion blur, and the camera motion will be ignored.

>Enable Depth Of Field

• This checkbutton enables the native Krakatoa Depth Of Field effect.
• NOTE that the 3ds Max MultiPass Depth Of Field effect is currently NOT supported.

>Allocate BokehBlendInfluence

• Availabke in Krakatoa MX 2.6.1 and higher.
• When unchecked (default),

Depth of Field Sample Rate

• Krakatoa renders particle Depth Of Field by calculating the disk area a particle would occupy in the image plane based on the current Depth of Field settings and then filling this area by drawing multiple samples of the same particle with random positions within the disk.
  • This value controls the number of samples to be drawn for each particle.
  • Lower values will cause less samples to be drawn thus speeding up the final pass but reducing quality.
  • High values will increase the number of samples and improve quality at costs of render time.
  • Using the [>>] button next to the value spinner, you can access predefined Sample Rate values as well as add new presets or remove existing presets.

Particle Render Mode

• This drop-down list can be used to switch between rendering to the frame buffer and saving to disk file:

Render Scene Particles

• In this mode, Krakatoa will render (shade) the particles according to the current settings.

Save Particles To File Sequence

• In this mode, Krakatoa will save the positions and optionally other data like Particle Colors and Normals to a PRT file.
• PRT files can be used to cache particle systems to disk for faster per-frame access and can also be used to load the same particles multiple times in the same scene with Position/Rotation/Scale/Count animation possibilities.
• When selected, the area around the saving controls will turn red.

Light Scene Particles

• This is a special version of the Render Scene Particles mode which performs the loading and lighting calculations of all particles without actually drawing the particles into a final image.
• It is meant to be used mainly for generating attenuation maps for shadow casting on geometry objects and could be also used to precache particles for later rendering using LCache and PCache.
• When selected, the area around the saving controls will turn yellow.

Load Percentage

• This spinner introduced in Krakatoa v1.1.0 controls the percentage of all particles scheduled for rendering to be loaded into memory.
• The percentage is calculated using the total concatenated particle stream after all particles have been pre-processed (loaded and shaded) but before sorting, lighting and rendering.
• Thus, it does not shorten loading times, but speeds up the lighting and rendering passes.
  • The value can be a floating point value between 0.0 and 100.0 %.
  • It affects all particles from all sources, including Particle Flow, Thinking Particles, Max Legacy Particles, Geometry Vertices, PRT Loaders and PRT Volumes.
  • Using the [>>] button next to the value spinner, you can access predefined Percentage values as well as add new presets or remove existing presets.

NOTE: If you are using only PRT Loaders, it is a better idea to use their Render Percentage values because they are applied at loading time before any shading is performed. As already mentioned above, the global percentage is applied AFTER the loading.

Use Particles From

• This group of checkbuttons controls which particle systems in the scene will be rendered (or saved).

PF Geo.

• Include Particle Flow particles whose Render Operator is set to Geometry type.
• ON by default.

PF Phan.

• Include Particle Flow particles whose Render Operator is set to Phantom type.
• ON by default.

PF BBox

• Include Particle Flow particles whose Render Operator is set to Bounding Box type.
• OFF by default.

Legacy

• Include all legacy 3ds Max particle systems like Snow, Spray, SuperSpray, PCloud and PArray.
• ON by default.

Thinking

• Include all particles contained in Cebas Thinking Particles systems.
• OFF by default.

PRT FFX

• Include particles of Krakatoa PRT FumeFX objects that seed from Sitni Sati’s FumeFX Simulation grids.
• ON by default.

Phoenix

• Include particles contained by Chaos Group Phoenix FD simulations.
• ON by default.

Geo. Verts

• Include vertices of renderable geometry objects that are not included in a Matte Objects Named Selection Set.
• OFF by defalt.
• Spline Shapes will be considered geometry when rendering Geometry Vertices only if the Enable in Renderer option is checked.
• If Enable in Renderer is checked but Enable in Viewport is not, the Knots of the spline itself will be rendered.

PRT Loader

• Include particles loaded by Krakatoa PRT Loaders from particle file sequences.
• ON by default.

PRT Volume

• Include particles generated by Krakatoa PRT Volume objects.
• ON by default.

PRT Surface

• Include particles generated by Krakatoa PRT Surface objects.
• ON by default.

PRT Hair

• Include particles of Krakatoa PRT Hair objects.
• ON by default.

PRT Maker

• Include particle of PRT Maker objects.
• ON by default.

PRT Source

• Include particles of PRT Source objects.
• ON by default.

PRT Field

• Include particles of Stoke PRT Field objects converting Field data to particle clouds.
• ON by default.

Stoke

• Include particles of Stoke Particle Simulation objects.
• ON by default.
• Any combination of these options can be toggled on and off at the same time for flexible inclusion and exclusion of particle types.
• To exclude specific objects of any included category, hide the object or its layer, or disable its Renderable object property.

Why use different PFlow Render Types?

The various PFlow Render Types allow for an additional level of flexibility when deciding which particles to render within a PFlow system.

• Say that you have an event giving birth to 100 particles which, when triggered by a Collision Spawn, create 1000 particles each and send them out to another Event.
• If you want to render the resulting 100,000 particles in the second Even, but you do not want to render the original 100 particles, you can
  • Set a local Render Operator with Phantom Type in the first Event
  • Set a local Render Operator of Geometry Type in the second event,
  • Uncheck “PF Phan.” in the Krakatoa GUI
• and you will render only the PF Geo. particles born by the Spawn operator.

Particles Source Presets

• The Presets button was added in v1.1.1 to allow for faster setting of the particle source options.
• Separate user defaults can be stored for the different “Particle Render Mode” options.
• The option Switch to User Default on Particle Render Mode change is enabled by default and stored in the local INI settings.
  • When on, switching the Particle Render modes will cause the Use Particles From defaults associated with the selected mode to be switched automatically.

For example,

• If you are constantly saving particles from Particle Flows, but rendering the resulting particle sequences from PRT Loaders, you could
  • Set the Save… mode to be associated with “PF Geo,”, “PF Phan.” and “PF BBox”,
  • Set the Render… mode to “PRT Loader”
• This lets you avoid the manual checking and unchecking of options each time you change the rendering mode!

Using PFlow None Mode

• The Particle Flow Render>None mode is not explicitly listed in the “Use Particles From” set of controls.
• In versions prior to 1.1.1, setting a Particle Flow to None mode would have excluded it completely from rendering since there was no way to specify it as a particle source.
• This was changed in Krakatoa 1.1.1 and higher to allow for some advanced setups that were previously impossible.
• The new behavior is to update Particle Flow systems that are set to None render mode, but not render any particles from them.
• This can be useful when one Particle Flow system is using a second Particle Flow system for driving its particles, for example using a Particle Flow Data Operator.
  • The driving particle system must be updated by Krakatoa during rendering in order for the driven particle system to access valid data in the Data Operator.
  • Previously, the only solution in this situation was to set the Density of the driving particles to 0 to make them invisible, but it caused them to be saved to the PRT file, increasing its size and causing even more problems when reloading such a system back into Particle Flow.
  • Now the Render operator of the driving system can be set to None and the particles will only be updated but will not be saved.

Particle Cache and Lighting Cache

• Two checkbuttons next to the RENDER button provide access to the Manual Particle Cache feature of Krakatoa.
• Since Krakatoa v1.1.0, only necessary channels will be loaded into memory.
• Thus, if a channel has not been cached yet but is requested, the cache will be rebuilt automatically.
• For details on how the Particle Cache can be used to speed up render test iterations, please see the topic Particle Cache and Lighting Cache.

• Both caches are available when rendering a single frame or a range of frames, but in the latter case the SAME particles from the frame that has been cached will be rendered throughout the whole animation. In other words, once a frame is cached, changing the scene time will NOT render a different frame unless the PCache is rebuilt again using one of the methods described above.
• Right-clicking any of the Cache buttons will show a context menu with these entries:
  • In Memory: - Particle Cache Size in Megabytes - selecting the item will copy the value to the Log Window.
  • Clear Lighting Cache Only - clears the data of the Lighting Cache, while keeping all other particle channels in memory.
  • Clear Both Caches - releases the memory used by PCache and LCache.
  • Keep Last Frame In Cache option - controls the memory management behavior of the PCache as described above. When checked, memory will not be flushed after each frame thus allowing you to enable PCache AFTER a frame was rendered. When unchecked, the memory will be flushed after each frame so enabling PCache will require reloading of particles into memory.
  • Use Cache In Slave Mode option - controls whether the caches will be used when rendering on the network. By default, the state of the Cache options will be ignored when 3ds Max is in slave mode (as opposed to workstation mode). You can check this option to force the Caches to be used in slave mode, for example when rendering a static particle cloud with a moving camera on a single machine.

Cache Indicator

• The cache indicator found between the two Cache buttons shows the state of the cache at a glance:
  • When gray, no particle data is found in memory.
  • When green, particle data was found in memory and all channels required by the currently enabled rendering features of Krakatoa have been allocated - if the cache is enabled, it will be used and will speed up the next frame’s rendering.
  • When orange, particle data was found in memory and all required channels have been allocated, but changed have been made to render settings that cannot be applied due to the cache being on - the cache will be used, but the changes will be ignored. This mode was added in v1.6.0.
  • When yellow, particle data was found in memory, but at least one channel requested by a Krakatoa rendering feature was not found in memory.
    • Even if the cache is enabled, the particles will be reloaded to populate the missing channel and the next frame’s rendering will not be sped up.
    • If you turn off the option that requested the additional uncached channel, the indicator will turn back green/orange again and rendering will be accelerated using the cached channels.

For example

• Let’s say you rendered particles without Motion Blur and enabled PCache.
• The cache indicator is green and you can re-render the particles again and again from memory.
• If you check the >Enable Motion Blur option, the Velocity channel will be required to blur the particles, but that channel has not been cached previously in order to save memory.
• At this point, the cache indicator will turn yellow because the Velocity channel is needed but is not cached.
• You can also see the Memory Channels Rollout - Velocity will be listed with a minus sign.
• If you uncheck the >Enable Motion Blur option, the cache indicator will turn back green because all required channels are already in memory - the Velocity channel will be removed from the list of needed channels and you can render from memory again without reloading particle data.

RENDER / SAVE PARTICLES

• The RENDER button is a conveniently located large button in the heart of the Krakatoa GUI.
• Depending on other settings, it can be used to:
  • Fire off the Krakatoa rendering with the current configuration settings.
  • Render a preview frame while ignoring image output saving and time settings.
  • Save particles to disk.

>Iterative [X]

• When unchecked (default), the RENDER button will perform regular rendering using all settings.
• When checked,
  • 3ds Max will be set to Iterative rendering mode, and Krakatoa will render the current frame without saving the output image to disk (however, a sample will still be stored in the History Cache folder if “Save Image Sample” is checked in the “Presets and History” rollout)
  • The size of the rendered image can be affected via the context menu accessible via the [>>] button or by right-clicking the Iterative button.
    • Double Resolution - renders the image using two times the horizontal and vertical resolutions (4 times the number of pixels).
    • Full Resolution - by default, the context menu is set to [Full], rendering the image using the Render Setup dialog settings.
    • 1/2 Resolution - renders half the horizontal and vertical resolution, 4 times less pixels than the Full image.
    • 1/4 to 1/16 Resolution - multiple options to render smaller resolutions of the full output image.
• Click here for more information on the Iterative mode and its image scaling capabilities..

RENDER

• If the Particle Render Mode drop-down list is set to Render Scene Particles and the >Iterative checkbutton is not checked, the button will read RENDER.
• Pressing it will be analogous to clicking the Render button in the Render Scene dialog, or clicking the Quick Render icon in the 3ds Max toolbar.

RENDER FRAME - ITERATIVE MODE

Available in Krakatoa v1.1.0 and higher

• If the Particle Render Mode drop-down list is set to Render Scene Particles and the >Iterative checkbutton above the RENDER button is engaged, the button will read RENDER FRAME
• Pressing it will cause only the current frame to be rendered without saving the image to disk even if requested otherwise in the Render Scene Dialog.
• If the time settings are set to Active Time Segment, Range or Frames, these will be ignored.
• This mode is useful for doing quick iterative renders while tweaking parameters without having to turn off saving and switch the time mode to single frame.
• The >Iterative mode affects ONLY the functionality of the RENDER button in the Krakatoa GUI, NOT the functionality of the Render / Quick Render commands in the 3ds Max UI. Pressing those will perform regular rendering as if >Iterative were not checked.
• It will also NOT affect network rendering because it does not modify internal settings of Krakatoa, only GUI-level ones.
• Closing and reopening the Krakatoa GUI will disengage the >Iterative option.

SAVE PARTICLES

• When the Particle Render Mode is set to Save Particles To File Sequence, the button’s caption will read “SAVE PARTICLES”.
• You can still use the Render / Quick Render commands in the 3ds Max UI in this mode to save particles to disk.
• The >Iterative option will be grayed out when in this mode. Even if it is checked, it will be ignored.
• No Rendered Frame Window (Virutal Frame Buffer, VFB) will be shown when saving. The VFB will close when saving and open when rendering.

RENDER Context Menu

• Krakatoa provides a right-click context menu for the RENDER button to simplify and speed up the access to typical features of the Render Scene Dialog:
  • Open [Common] Tab In Render Setup Dialog… toggle - this option toggles the Render Setup Dialog’s Common tab on and off.
    • When the Render Setup dialog is open, a checkmark will appear in front of the option.
    • If the Render Setup dialog is closed, it will be opened at the Common tab.
    • If the Render Setup dialog is already open and on the Common tab, it will be closed.
    • If the Render Setup dialog is already open on a different tab, it will remain open and will be switched to the Common tab.
  • Open [Render Elements] Tab In Render Setup Dialog… toggle - this option toggles the Render Setup Dialog’s Render Elements tab on and off.
    • When the Render Setup dialog is open, a checkmark will appear in front of the option.
    • If the Render Setup dialog is closed, it will be opened at the Render Elements tab.
    • If the Render Setup dialog is already open and on the Render Elements tab, it will be closed.
    • If the Render Setup dialog is already open on a different tab, it will remain open and will be switched to the Render Elements tab.
  • Keep Render Scene Dialog Open - this option was introduced in Krakatoa 1.1.0. Due to a design peculiarity of 3ds Max, making any changes to the time and output settings in the Render Setup Dialog requires the closing and reopening of the dialog. This leads to an annoying flashing each time a setting is changed via the right-click menu.
    • When unchecked, the Render Setup Dialog will be closed if open and NOT opened again after the changes have been made. Most of the time, the right-click menu provides enough controls to select the desired timing and output file name. If the dialog is needed again, for example to change the Time Range, it can be opened using the previous menu item.
    • When checked, the Render Setup Dialog will be closed if open and opened again after the changes have been made. This is the same as in Krakatoa v1.0.0. The setting is sticky via INI file settings and will persist until changed again.
  • Save Render Output - this option toggles the Save File checkbox in the Render Setup Dialog on and off. When the Saving is enabled in the Render Setup Dialog, a checkmark will appear in front of the menu option. Disabled if there is no output filename defined or if Krakatoa is in SAVE PARTICLES mode.
  • Set Render Output Filename - this option allows you to browse for saving output and specify the output bitmap filename and type. When a valid path and name are entered in the Render Setup Dialog, a checkmark will appear in front of this menu option.
  • Explore Render Path - Opens the Windows Explorer at the output path specified in the Render Setup Dialog. Disabled if there is no output filename defined or if Krakatoa is in SAVE PARTICLES mode.
  • Single Frame - this option can be used to set the Output Time Mode to single frame using the current scene time.
  • Active Segment - this option can be used to set the Output Time Mode to a frame range using the current scene segment.
  • Custom Range - this option can be used to set the Output Time Mode to a frame range using the custom range in the Render Scene Dialog
  • Custom Frames - this option can be used to set the Output Time Mode to a frame list specified in the Render Scene Dialog.
  • Open Rendered Frame - this option only appears in the menu only if the specified render output filename already exists on disk.
    • In Rendered Frame Window (VFB)… - the image will be displayed in a 3ds Max Rendered Frame Window.
    • In External Viewer… - the image will be displayed in the external viewer registered with Windows.
    • In RAM Player… - the single frame will be displayed in the 3ds Max RAM Player.
    • As Sequence in RAM Player Channel A… - the complete image sequence will be loaded via an IFL Image File List file in Channel A of the 3ds Max RAM Player.

Advanced Overrides

>Ignore Missing Particles

• This special override causes Krakatoa to ignore any missing particle files when rendering locally or on the network.
• This is very useful when test rendering scenes the PRT files for which are still being generated.
• In the past, Krakatoa would have failed with an error message if even one of the PRT files could not be found.
• Since this mode can be dangerous in real-world production (producing flickering renders due to missing files), its checkbutton will always be red regardless of UI color customizations.

>Fast PRT Loading

• This checkbutton is a duplicate of the “System Preferences” > “Multi-Thread Partition LOADING” option.
• When unchecked (default), every file sequence in a PRT Loader will be processed sequentially.
• When checked, multiple file sequences (if any) in a PRT Loader will be processed in parallel to speed up loading performance.
• Note that the PRT Loading process can be
  • I/O Bound - if the storage medium (HDD, SSD, network storage) cannot keep up with the demand of the PRT Loader, the performance of the PRT loading will be I/O-bound.
  • CPU Bound - each PRT sequence contains a single zlib stream which is decompressed on a single thread.

WARNING!

• Enabling the multi-threaded loading when network renderng can easily saturate the bandwidth of a whole company!
• The button will always be displayed in RED regardless of the custom color schemes of 3ds Max and Krakatoa to warn the user that it is on.
• We recommend using this feature only when accessing data from a fast local storage, e.g. a Solid State Drive or FusionIO card.

Shadow Data Saving

>Save Attenuation Maps

• This option enables the saving of Deep Attenuation Maps by Krakatoa Shadows Generators assigned to scene lights.
  • When unchecked, no shadow data will be saved to disk.
  • When checked, any Krakatoa Shadows Generator found in the scene will save Attenuation Maps to disk.

Explore…

• Pressing this button will open the Krakatoa Shadows Explorer utility used to mass-assign and manage Krakatoa Shadows Generators in the scene.

Other Feature States Overview group of controls

• The checkbuttons in this group of controls provide a quick overview of the major settings found in other rollouts than the Main Controls one.
• These checkbuttons have multiple functions:
  • They will reflect the state of the corresponding features in the other rollouts.
  • Changing their state will switch the corresponding features on and off in the other rollouts.
  • Right-clicking them will focus the UI at the corresponding remote rollout. This can be useful to quickly adjust detailed settings and then switch back to the Main Controls rollout by pressing the Back To Main Controls button found on top of each rollout.
• The checkbuttons represent the following options:
  • >Override Color - duplicates the >Override Color option in the Global Render Values rollout.
  • >Override Emission - duplicates the >Override Emission option in the Global Render Values rollout.
  • >Override Absorption - duplicates the >Override Absorption option in the Global Render Values rollout.
  • >Override Density - duplicates the >Override Density option in the Global Render Values rollout.
  • >Use Matte Objects - duplicates the >Use Matte Objects option in the Matte Objects rollout.
  • >Save Multi.Layers - duplicates the >Save Multiple Layers option in the Matte Objects rollout.
  • >Use Depth Map Files - duplicates the >Load Initial Depth Map File Sequence option in the Matte Objects rollout.
  • >Use APME - duplicates the >Use Ambient Participating Medium Extinction (AMPE) option in the Ambient PME rollout.

Additional Dialogs Navigation

• The bottom row of buttons in the Main Controls rollout provides quick access to dialogs and floaters that are not part of the Krakatoa Renderer GUI but are vital to the Krakatoa workflows.
• These include:
  • Schematic - opens the Schematic Flow explorer utility which provides an overview of the various render/saving stages of the Krakatoa renderer and can be used to debug the flow of data through the renderer and control some of its settings from a central location.
  • PD Viewer - opens the Particle Data Viewer utility which lets you peek into the particle data channels of PRT Loader and PRT Volume objects.
  • PRT Scan - opens the PRT Analyzer utility which can be used to overview the particle count and memory requirements of PRT Loaders and some other particle systems.
  • Explorers - opens the Krakatoa Explorers floater which provides rollouts to overview and manage scene particle systems, PRT Loaders and Thinking Particles Groups.
  • Preferences - opens the Krakatoa Preferences floater which provides rollouts to overview and change the System, User Interface Behaviors and UI Color preferences of Krakatoa.
  • Notes - opens the Krakatoa User Notes dialog which can be used to store descriptions of the Krakatoa setup or the scene content as a means to communicate between artists on a team.
  • Log - opens the Krakatoa Log Window.