From Kraytracing Wiki

Contents 1 Kray Master Plugins 1.1 Quick Linear Workflow plugin 1.1.1 Input Tone Map 1.1.2 Parameter 1.1.3 Exposure 1.1.4 HSV 1.1.5 Affect backdrop 1.1.6 Affect textures 1.1.7 Affect lights 1.2 Kray Override - Surface Override GUI 1.2.1 Enable Override 1.2.2 Override with color 1.2.3 Opaque to light 1.2.4 Pure color 1.2.5 Pure diffuse 1.2.6 Disable ... 1.3 Kray Buffers 2 Kray Custom Object plugins 2.1 Kray Instances 2.1.1 Object to clone 2.1.2 Object to Follow 2.1.3 Rotation 2.1.4 Use normals 2.1.5 Scaling 2.1.6 Lock XYZ Size 2.1.7 Use Color 2.1.8 Use custom object 2.1.9 Example scene 3 Kray Surface Shaders 3.1 Kray Surface Options 3.1.1 Visible 3.1.2 Control diffuse model 3.1.3 Cache Irradiance 3.1.4 Caustics 3.1.5 Reflect Caustic photons 3.1.6 Control FG rays 3.1.7 Control Reflection Blur 3.1.8 Trace direct 3.1.9 Accurate reflection 3.1.10 Force indirect luminosity 3.2 Kray Indirect Rays 3.2.1 Desaturate 3.2.2 Multiply 3.2.3 Limit Dynamic Range 3.3 Kray Light Portal 3.3.1 Light 3.3.2 Enable Photons Portal 3.3.3 Enable Caustics Portal 3.4 KrayPhotonMultiplier Surface Shader 3.4.1 Luminosity number multiplier 3.4.2 Luminosity power multiplier 3.4.3 Diffuse number multiplier 3.4.4 Diffuse power multiplier 4 The Kray motion modifier 4.1 KrayPhotonMultiplier 4.1.1 Photon Number multiplier 4.1.2 Photon Power multiplier 5 Modeler Plugins 5.1 KrayAutoParts

Kray Master Plugins

Quick Linear Workflow plugin

If you ever played with gamma values in Kray GUI you have probably noticed that increasing gamma can bring to washed out looks and changing color tones in textures. This plugin will help you get better and more accurate colors in your renders. The plugin tonemaps the incoming colors and textures so that they are calculated properly within Kray. Parameters:

Input Tone Map

with this settings you choose the tonemap of your input images and colors. Usualy this setting should be kept at Gamma.

Parameter

This is the value of your input tonemap. Usually images on computers have gamma value of 2.2 so this is what you enter here.

Exposure

If you want to increase or decrease the exposure of your input colors/textures enter appropriate value here

HSV

This parameter tells KRay that input images are tonemapped in HSV mode.

Affect backdrop

will use quick LWF settings for backdrop

Affect textures

will use quick LWF settings for textures

Affect lights

will use quick LWF settings for light colors

Kray Override - Surface Override GUI

This is a master plugin that will help you control surface override settings.

Enable Override

Will let you quickly enable/disable override in Kray.

Override with color

Will render the object in a specified color while keeping all other channels intact (diffuse, reflection, transparency, ...).

Opaque to light

Will prevent light from passing through transparent surfaces.

Pure color

Will render surfaces in pure matte color (no textures, no shading).

Pure diffuse

Will render surfaces as a pure diffuse without any textures, colors, reflections, etc.

Disable ...

Disable Textures will turn off all textures. Disable Refl/Refr blurring will turn off all reflection and refraction blurring. Disable Luminosity will turn off all luminosity. Disable reflections will not render any reflections. Disable transparency will render transparent surfaces as opaque. Disable translucency will not render translucency.

Here's an example of different override options:

Kray Buffers

Kray Buffers GUI will lets you choose which buffers you want to output from Kray. Kray will create a separate file with a buffer name in the filename.

The settings are pretty self explanatory so we will not get in depth about each buffer here.

Kray Custom Object plugins

Kray Instances

Kray instances plugin allows you to easily place thousands of instances into your scene. The plugin allows random scale and rotation and som other useful options. It's a Custom Object plugin that should be applied to the object (template) that defines position of your instances. The template can be either polygon mesh, 1 point polygons or pure points (no polys).

Object to clone

Choose object that will be instanced

Object to Follow

Here you can choose object that instances will “follow”. Instances will use it’s rotation and scale parameters.

Rotation

Here you define random rotation settings.

Use normals

Turning this ON will align instances to template mesh normals (only works on polygons!).

Scaling

Here you define random scaling settings.

Lock XYZ Size

Turning this ON will lock X, Y, Z scale parameters so object will be resized equally on all axis.

Use Color

Turning this ON will use color from the template object and color filter the instances.

Use custom object

You can use special object to place your instances. The default object is triangle 1mx1mx1m in size with a 2 point polyline defining it’s axis. This object defines position, orientation and scale of the instances. Note: you can still apply random rotation/scale values on top.

Example scene

Download an example scene here: Kray Instancing example scene

Kray Surface Shaders

Kray Surface Options

The KraySurfaceOptions Shader can be used to change various Kray settings for each surface.

Visible

Turns the visibility (from everything, camera, rays, reflection etc) of the surface on/off.

Control diffuse model

Enables you to change the GI model for this surface only. The available models are all that are normally available to Kray : Raytrace, Photon Filtered, Photon Filtered+Raytrace Direct, Photon Mapping, Path Tracing.

Cache Irradiance

(only available with Photon Mapping and Path Tracing) Allows you to turn on or off Irradiance Caching for this surface.

Caustics

Allows you to turn on or off caustics for this surface.

Reflect Caustic photons

In a scene that has Caustics on, unchecking this will disable the production of reflection caustic photons from this surface. If the scene has Caustics off this setting will do nothing.

Control FG rays

Allows you to use different number of rays for this surface, so you can use less rays for areas

Control Reflection Blur

Allows you to use different number of reflection rays per surface, so you can for example use more rays for the floor surface and less for the rest of the scene.

Trace direct

Same as trace direct light reflection in the quality tab.

Accurate reflection

Allows you to override the Blurring accuracy limit setting in Kray rendering options and use the FG solution instead of photon filtered for reflection of this surface.

Force indirect luminosity

Allows you to make a luminous polygon emit light indirectly regardless of the settings in the Quality tab of the Kray rendering options.

Kray Indirect Rays

Desaturate

This can be used to control color bleeding. The percentage represents how much the light that bounces of the surface will be desaturated.

Multiply

Multiply can increase or decrease the amount of light that bounces off the surface.

Limit Dynamic Range

Limits the dynamic range of the indirect rays that leave the surface. Can be used on luminous geometry that emit light indirectly. The emitted light is clamped to limit dynamic range value eliminating over bright values which effectively reduces possible splotches (but also the power of the emitted light gets reduced as well), while the surface itself appears to be very bright. This is an unrealistic function but it can be a useful tool too when you want to improve your result without caring too much for realism.

Kray Light Portal

See also Using Lightportals tutorial.

The KrayLightPortal can be used to make some surfaces act as Light Portals.

Light

This Drop down list enables you to link this light portal to a specific light. If you want to link multiple lights to a specific light portal you can add the KrayLightPortal shader multiple times on the same surfaces.

Enable Photons Portal

Ticking this will make this surface act as a Light portal

Importance: This percentage amount to the percentage of photons that will be aimed at this surface.

All lightportals importance: This shows you the added importance of all light portals. If the sum of all light portals exceeds 100% the percentage of the other light portals will be reduced so that the sum is 100% once you exit the light portals panel.

Enable Caustics Portal

Importance: This percentage amount to the percentage of caustic photons that will be aimed at this surface.

All lightportals importance: This shows you the added importance of all light portals. If the sum of all light portals exceeds 100% the percentage of the other light portals will be reduced so that the sum is 100% once you exit the light portals panel.

KrayPhotonMultiplier Surface Shader

With this shader you can control the amount and intensity(power) of photons leaving the surface. This is similar to power multiplier setting in the Kray GUI - Photons tab but it work on per surface basis.

Luminosity number multiplier

You can increase the number of photons emitted from Luminous surface by increasing this number.

Luminosity power multiplier

You can increase the power (intensity) of the photons emitted from Luminous surface by increasing this number.

Diffuse number multiplier

You can increase the number of the photons bouncing from diffuse surface by increasing this number.

Diffuse power multiplier

You can increase the power (intensity) of the photons bouncing from diffuse surface by increasing this number. This can be helpful for example in a room with dark floor where bounced photons would be few. Increasing this setting will make the room lighter as if the floor was brighter.

The Kray motion modifier

KrayPhotonMultiplier

KrayPhotonMultiplier modifier controls how much photons a light source emits. You can apply this modifier to a Light or an object containing luminous polygons.

You should assign this shader to a light source that is not emitting enough photons or if you want the power of light to be stronger.

Photon Number multiplier

This setting will increase the number of photons the light emits.

Photon Power multiplier

This setting will increase the power of the photons the light emits. Note that the intensity of the direct light will not be stronger. Only bounced light will be brighter.

You must experiment to find the right value but that's usually quite easy: just render in Photon estimate - Global unfiltered or Precomputed mode and find the right balance.

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Here's an example of a render without using PhotonNumberMultiplier:

Unfiltered: No PhotonNumberMultiplier

Precomputed: No PhotonNumberMultiplier

And here's an example of a render with PhotonNumberMultiplier 100000.0:

Unfiltered: With PhotonNumberMultiplier

Precomputed: With PhotonNumberMultiplier

Modeler Plugins

KrayAutoParts

When using direct luminosity model, Kray will only recognize 1 light per luminous surface/object. But when you assign different part names then Kray will treat each part as a separate light source.

This plugin automatically assigns part names to selected polygons. Each group of polygons that is connected will get one part name.

KrayAutoParts.p is available as a separate download from the Kray website.