A classic lighting scheme for key, fill and rim lights. Use this light for a basic illumination of objects in a scene.
Key Light provides the main source of object illumination - it is the most dominant light source and casts the darkest shadows.
Fill Light extends the Key Light illumination and makes the object more visible. It simulates secondary light sources such as table lamps, environmental sources other than the sun, or reflected and bounced lights.
Note
Fill Light should come from an angle that is opposite to the Key Light.
Rim light creates a bright line of light around the edge of an object. It is usually used to separate the object from its background.
Houdini also provides a fourth light, called Bounce light. The bounce light reflects light onto an object based on light location to give the effect of natural or available light. This type of lighting also softens the harshness of the Key Light.
Bounce lights are optimal when doing micropolygonal rendering - use bounce lighting when not doing PBR.
Parameters
Transform
| Keep Position When Parenting | When the object is re-parented, maintain its current world position by changing the object’s transform parameters. | ||||||||||||
| Pre-transform menu | This menu contains options for manipulating the pre-transform values. The pre-transform is an internal transform that is applied prior to the regular transform parameters. This allows you to change the frame of reference for the translate, rotate, scale parameter values below without changing the overall transform.
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| Transform Order | The left menu chooses the order in which transforms are applied (for example, scale, then rotate, then translate). This can change the position and orientation of the object, in the same way that going a block and turning east takes you to a different place than turning east and then going a block. The right menu chooses the order in which to rotate around the X, Y, and Z axes. Certain orders can make character joint transforms easier to use, depending on the character. | ||||||||||||
| Translate | Translation along XYZ axes. | ||||||||||||
| Rotation | Degrees rotation about XYZ axes. | ||||||||||||
| Uniform Scale | Scale the object uniformly along all three axes. | ||||||||||||
| Look At | Object to point to. Constrains an object so its | ||||||||||||
| Look At Up Vector | When specifying a look at, it is possible to specify an up vector for the look at. This controls the roll of this object when looking at the look at object.
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| Path Object | A reference to the curve node or object you want this object to follow. | ||||||||||||
| Roll | The orientation of the object around the path. | ||||||||||||
| Position | The position of the object along the path. If the primitive number does not exist, then it is wrapped back to the beginning. So for numbers greater than Keyframe this value to animate the object moving along the path. Note The Follow Path tool on the shelf automatically sets keyframes on this parameter that you may want to edit or replace. The Parameterization option controls how position values between 0 and 1 correspond to knots on the path curve. | ||||||||||||
| Parameterization | Controls how the Position parameter is translated into a point on the path curve. Use Arc-length (the default) to interpolate the position values evenly along the physical length of the curve. Use Uniform to distribute the position values between the knots of the curve. This lets you slow down the object at certain points by bunching up knots in the path curve. However, it is much more convenient to simply edit the animation curve to control the speed of the object along the path. | ||||||||||||
| Orient Along Path | Orient the object according to the path’s curvature. | ||||||||||||
| Orient Up Vector | The direction vector of the object’s Y axis to orient with. | ||||||||||||
| Auto-Bank factor | Controls automatic banking of the object as it turns corners. Set this to |
Light
| Categories | Defines the set membership of this object. | ||||
| Look At Camera | The camera which views the subject. This allows the light rig to orient itself properly, so that the key light illuminates from the front, while the rim light illuminates from the back, etc. | ||||
| Camera Up Vector | How the rig rotates around the viewing axis to align it with the camera up vector.
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| Use Only Camera Azimuth | Light rig rotates only horizontally (i.e., only around the vertical axis) regardless of the animation path of the camera. | ||||
| Lights Enabled | Disables all lights in the viewport when turned off. | ||||
| Use lights look-at target | Fine-tuning of the exact point where light components are directed. | ||||
| Lights Look At | The point in space at which the component lights are directed when Use lights look-at target is enabled |
Key Light
| Light Enabled | The Key Light illumination. When turned off, equivalent to setting the light intensity to 0. |
| Show Direction Manipulator | The direction the Key Light is coming from. |
| Direction To Light | Changes the direction of the Key Light as determined by the value of the specified axis. It is a direction vector towards the component light within the three point light rig. |
| Translate | Adjusts the light position. |
| Rotate | Adjusts the light rotation. |
Light
| Light Type | Type of light used to illuminate an object.
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| Light Color | The color of light illuminated on the object. | ||||||
| Light Intensity | Amount of light placed on the selected color. For example, if the intensity is 0, the light is disabled. | ||||||
| Diffuse Contribution | Diffuses illumination on a given surface. | ||||||
| Specular Contribution | Provides specular highlights when illuminating an object surface. |
Spot Light Options
| Note | You can only change the Cone parameters when using a Spot Light light type. |
| Cone Angle | The size of the spotlight beam. Indicates the spotlight cone’s degree of wideness. |
| Cone Delta | Penumbra degree for spotlights. |
| Cone Rolloff | Shape exponent of penumbra (larger = sharper). |
| Projection Map | Specifies the image that gets projected. The viewing angle of the light will determine the area of projection. |
| Use cone angle for field of view | Defines the field of view when rendering shadow maps or using a projection map with a spot light. Turn off this parameter to enable the Projection Angle or Orthographic Width parameters. |
| Projection Angle | The viewing angle used for depth map generation when perspective view is used. |
| Orthographic Width | Controls the field of view for depth map generation. |
Shadows
| Shadow Type |
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| Shadow Mask | Mask objects that occlude for the light source. Shadow rays intersect objects when using ray-traced shadows. If you use depth map shadows, these objects appear in the depth map. | ||||
| Shadow Bias | The bias when computing shadows from Key Light. If occluders are within this small distance, they are not considered shadowers. This is to prevent self-shadowing artifacts due to the limited resolution of depth map shadows. | ||||
| Shadow Intensity | Amount of light blocked by occluders. Decrease the shadow intensity to ensure the occluders do not block all the light and allow some illumination through. | ||||
| Shadow Quality | Adjusts the quality of lookups when evaluating standard shadow maps or blurred shadows. | ||||
| Shadow Softness | A blur on the shadow map when using depth mapped shadows. This is relative to micropolygon sizes when rendering with “Micropolygon Rendering”. | ||||
| Shadow Blur | Controls a fractional blur of the shadow map image when rendering. Use Shadow Blur to blur the map disregarding the surface derivatives. | ||||
| Transparent Shadows | The surface shader of occluders are evaluated to determine opacity. Turning this option on will cause deep shadow maps to be used when shadowing using Depth Map Shadows. Note The parameters below are Deep shadows. They are produced by default when rendering “Depth Map Shadows” with Transparent Shadows enabled. Their advantages include:
Deep shadow maps store the opacity of any translucent objects the light ray passes through as well as the depth of the final opaque surface. Note that Deep shadows use significantly more disk space than plain depth maps. See Shadow Type for additional information on Deep shadows. |
Depth Map Options
| Auto-generate Shadow Map | Path is automatically generated. |
| Shadow Map | The path to the shadow map. |
| Resolution | The resolution of the shadow map. It is recommended that you keep the resolution the same in X and Y. |
| Pixel Samples | The number of pixel samples when rendering shadow maps. This is more important when using deep shadow maps (transparent shadows). |
| Near Clipping | Distance to the near clipping plane. |
| Far Clipping | Distance to the near clipping plane. |
| Depth Map Motion Blur | When rendering deep shadow maps, it is possible to capture motion blur. If motion blurred shadows are desired, it’s important to turn on Transparent Shadows. |
Fill Light
| Light Enabled | The Fill Light illumination. When turned off, equivalent to setting the light intensity to 0. |
| Show Direction Manipulator | The direction the Key Light is coming from. |
| Direction To Light | Changes the direction of the Key Light as determined by the value of the specified axis. It is a direction vector towards the component light within the three point light rig. |
| Translate | Adjusts the light position. |
| Rotate | Adjusts the light rotation. |
Light
| Light Type | Type of light used to illuminate an object.
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| Light Color | The color of light illuminated on the object. | ||||||||
| Light Intensity | Amount of light on the selected color. For example, if the intensity is 0, the light is disabled. | ||||||||
| Diffuse Contribution | Diffuses illumination on a given surface. | ||||||||
| Specular Contribution | Provides specular highlights when illuminating an object surface. |
Spot Light Options
| Note | You can only change the Cone parameters when using a Spot Light light type. |
| Cone Angle | The size of the spotlight beam. Enter the degree of wideness the spotlight’s cone should be. |
| Cone Delta | Penumbra degree for spotlights. |
| Cone Rolloff | Shape exponent of penumbra (larger = sharper). |
| Projection Map | Specifies the image that gets projected. The viewing angle of the light will determine the area of projection. |
| Use cone angle for field of view | Defines the field of view when rendering shadow maps or using a projection map with a spot light. Turn off this parameter to enable the Projection Angle or Orthographic Width parameters. |
| Projection Angle | The viewing angle used for depth map generation when perspective view is used. |
| Orthographic Width | Controls the field of view for depth map generation. |
Area Light Options
| Area Shape | The shape of the area light.
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| Area Samples | The number of lighting samples used to evaluate the light source. | ||||||||
| Area Size | A uniform scale on the area light. | ||||||||
| Cosine Falloff | Area light rays are weighed with a cosine of a ray direction with respect to the normal area light. | ||||||||
| Single Sided | Specifies whether the area light emits light from only one side. | ||||||||
| Use full sphere for environment | Uses full sphere rather than limit the environment to hemisphere. | ||||||||
| Use Area Map | Currently only used for environment lights. | ||||||||
| Area Map | Currently only used for environment lights. The area map will be tinted by the color of the light source. |
Shadows
| Shadow Type |
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| Shadow Mask | Mask objects that occlude for the light source. Shadow rays intersect objects when using ray-traced shadows. If you use depth map shadows, these objects appear in the depth map. | ||||
| Shadow Bias | The bias when computing shadows from Fill Light. If occluders are within this small distance, they are not considered shadowers. This is to prevent self-shadowing artifacts due to the limited resolution of depth map shadows. | ||||
| Shadow Intensity | Amount of light blocked by occluders. Decrease the shadow intensity to ensure occluders do not block all the light, allowing some illumination through. | ||||
| Shadow Quality | Adjusts the quality of lookups when evaluating standard shadow maps or blurred shadows. | ||||
| Shadow Softness | A blur on the shadow map when using depth mapped shadows. This is relative to micropolygon sizes when rendering with “Micropolygon Rendering”. | ||||
| Shadow Blur | Controls a fractional blur of the shadow map image when rendering. Use Shadow Blur to blur the map disregarding the surface derivatives. | ||||
| Transparent Shadows | Evaluates the surface shader of occluders to determine opacity. Turning this option on causes deep shadow maps to be used when using Depth Map Shadows. Note The parameters below are Deep shadows. They are produced by default when rendering “Depth Map Shadows” with Transparent Shadows enabled. Their advantages include:
Deep shadow maps store the opacity of any translucent objects the light ray passes through, as well as the depth of the final opaque surface. Note that Deep shadows use significantly more disk space than plain depth maps. See Shadow Type for additional information on Deep shadows. |
Depth Map Options
| Auto-generate Shadow Map |
Path is automatically generated.
| Shadow Map | The path to the shadow map. |
| Resolution | The resolution of the shadow map. It is recommended that you keep the resolution the same in X and Y. |
| Pixel Samples | The number of pixel samples when rendering shadow maps. This is more important when using deep shadow maps (transparent shadows). |
| Near Clipping | Distance to the near clipping plane. |
| Far Clipping | Distance to the far clipping plane. |
| Depth Map Motion Blur | When rendering deep shadow maps, it is possible to capture motion blur. If you desire motion blurred shadows, turn on Transparent Shadows. |
Rim Light
| Light Enabled | Rim Light illumination. When turned off, equivalent to setting the light intensity to 0. |
| Show Direction Manipulator | Displays the direction the Rim Light is coming from. |
| Direction To Light | |
| Translate | Adjusts the light position. |
| Rotate | Adjusts the light rotation. |
Light
| Light Type | Type of light used to illuminate an object.
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| Light Color | The color of light illuminated on the object. | ||||||||
| Light Intensity | Amount of light on the selected color. For example, if the intensity is 0, the light is disabled. | ||||||||
| Diffuse Contribution | Diffuses illumination on a given surface. | ||||||||
| Specular Contribution | Provides specular highlights when illuminating an object surface. |
Spot Light Options
| Note | You can only change the Cone parameters when using a Spot Light light type. |
| Cone Angle | The size of the spotlight beam. Indicates the spotlight cone’s degree of wideness. |
| Cone Delta | Penumbra degree for spotlights. |
| Cone Rolloff | Shape exponent of penumbra (larger = sharper). |
| Projection Map | Specifies the image that gets projected. The viewing angle of the light will determine the area of projection. |
| Use cone angle for field of view | Defines the field of view when rendering shadow maps or using a projection map with a spot light. Turn off this parameter to enable the Projection Angle or Orthographic Width parameters. |
| Projection Angle | The viewing angle used for depth map generation when perspective view is used. |
| Orthographic Width | Controls the field of view for depth map generation. |
Shadows
| Shadow Type |
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| Shadow Mask | Mask objects that occlude for the light source. Shadow rays intersect objects when using ray-traced shadows. If you use depth map shadows, these objects appear in the depth map. | ||||
| Shadow Bias | The bias when computing shadows from Rim Light. If occluders are within this small distance, they are not considered shadowers. This is to prevent self-shadowing artifacts due to the limited resolution of depth map shadows. | ||||
| Shadow Intensity | Amount of light blocked by occluders. Decrease the shadow intensity to ensure the occluders do not block all the light and allow some illumination through. | ||||
| Shadow Quality | Adjusts the quality of lookups when evaluating standard shadow maps or blurred shadows. | ||||
| Shadow Softness | A blur on the shadow map when using depth mapped shadows. This is relative to micropolygon sizes when rendering with “Micropolygon Rendering”. | ||||
| Shadow Blur | Controls a fractional blur of the shadow map image when rendering. Use Shadow Blur to blur the map disregarding the surface derivatives. | ||||
| Transparent Shadows | Evaluates the surface shader of occluders to determine opacity. Turning this option on causes deep shadow maps to be used when using Depth Map Shadows. Note The parameters below are Deep shadows. They are produced by default when rendering “Depth Map Shadows” with Transparent Shadows enabled. Their advantages include:
Deep shadow maps store the opacity of any translucent objects the light ray passes through, as well as the depth of the final opaque surface. Note that Deep shadows use significantly more disk space than plain depth maps. See Shadow Type for additional information on Deep shadows. |
Depth Map Options
| Auto-generate Shadow Map | Path is automatically generated. |
| Shadow Map | The path to the shadow map. |
| Resolution | The resolution of the shadow map. It is recommended that you keep the resolution the same in X and Y. |
| Pixel Samples | The number of pixel samples when rendering shadow maps. This is more important when using deep shadow maps (transparent shadows). |
| Near Clipping | Distance to the near clipping plane. |
| Far Clipping | Distance to the far clipping plane. |
| Depth Map Motion Blur | When rendering deep shadow maps, it is possible to capture motion blur. If you desire motion blurred shadows, turn on Transparent Shadows. |
Bounce Light
| Light Enabled | The Bounce Light illumination. When turned off, equivalent to setting the light intensity to 0. |
| Show Direction Manipulator | The direction the Rim Light is coming from. |
| Direction To Light | Changes the direction of the Rim Light as determined by the value of the specified axis. It is a direction vector towards the component light within the three point light rig. |
| Translate | Adjusts the light position |
| Rotate | Adjusts the light rotation. |
Light
| Light Type | Type of light used to illuminate an object.
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| Light Color | The color of light illuminated on the object. | ||||||||
| Light Intensity | Amount of light on the selected color. For example, if the intensity is 0, the light is disabled. | ||||||||
| Diffuse Contribution | Diffuses illumination on a given surface. | ||||||||
| Specular Contribution | Provides specular highlights when illuminating an object surface. |
Spot Light Options
| Note | You can only change the Cone parameters when using a Spot Light light type. |
| Cone Angle | The size of the spotlight beam. Indicates the spotlight cone’s degree of wideness. |
| Cone Delta | Penumbra degree for spotlights. |
| Cone Rolloff | Shape exponent of penumbra (larger = sharper). |
| Projection Map | Specifies the image that gets projected. The viewing angle of the light will determine the area of projection. |
| Use cone angle for field of view | Defines the field of view when rendering shadow maps or using a projection map with a spot light. Turn off this parameter to enable the Projection Angle or Orthographic Width parameters. |
| Projection Angle | The viewing angle used for depth map generation when perspective view is used. |
| Orthographic Width | Controls the field of view for depth map generation. |
Area Light Options
| Area Shape |
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| Area Samples |
The number of lighting samples used to evaluate the light source.
| Area Size | A uniform scale on the area light. |
| Cosine Falloff | Area light rays are weighed with a cosine of a ray direction with respect to the normal area light |
| Single Sided | Specifies if the area light emits light from only one side. |
| Use full sphere for environment | Uses full sphere rather than limit the environment to hemisphere. |
| Use Area Map | Currently only used for environment lights. |
| Area Map | Currently only used for environment lights. The area map will be tinted by the color of the light source. |
Shadows
| Shadow Type |
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| Shadow Mask | Mask objects that occlude for the light source. Shadow rays intersect objects when using ray-traced shadows. If you use depth map shadows, these objects appear in the depth map. | ||||
| Shadow Bias | The bias when computing shadows from bounce Light. If occluders are within this small distance, they are not considered shadowers. This is to prevent self-shadowing artifacts due to the limited resolution of depth map shadows. | ||||
| Shadow Intensity | Amount of light blocked by occluders. Decrease the shadow intensity to ensure the occluders do not block all the light and allow some illumination through. | ||||
| Shadow Quality | Adjusts the quality of lookups when evaluating standard shadow maps or blurred shadows. | ||||
| Shadow Softness |
A blur on the shadow map when using depth mapped shadows. This is relative to micropolygon sizes when rendering with “Micropolygon Rendering”.
| Shadow Blur | Controls a fractional blur of the shadow map image when rendering. Use Shadow Blur to blur the map disregarding the surface derivatives. |
| Transparent Shadows |
Evaluates the surface shader of occluders to determine opacity. Turning this option on causes deep shadow maps to be used when using Depth Map Shadows.
Depth Map Options
| Auto-generate Shadow Map | Path is automatically generated. |
| Shadow Map | The path to the shadow map. |
| Resolution | The resolution of the shadow map. It is recommended that you keep the resolution the same in X and Y. |
| Pixel Samples | The number of pixel samples when rendering shadow maps. This is more important when using deep shadow maps (transparent shadows). |
| Near Clipping | Distance to the near clipping plane. |
| Far Clipping | Distance to the far clipping plane. |
| Depth Map Motion Blur | When rendering deep shadow maps, it is possible to capture motion blur. If you desire motion blurred shadows, turn on Transparent Shadows. |
Subnet
| Display | Whether or not this object is displayed. Turn on the checkbox to have Houdini use this parameter, then set the value to 0 to hide the object, or 1 to show the object. If the checkbox is off, Houdini ignores the value. |
| Output Transform | Allows you to choose the position in space that is defined by the output transform of the three point light node. Input 1 is the same as the input space (i.e - position of the input node). Choosing key light, for example, outputs the key light position. Any node subsequently parented to the output of the light rig will be positioned in that space. |
| Visible children | Space separated list of objects to display inside the subnet. Use This parameter lets you:
In a normal subnet you can simply go into the subnet and set the display flag on objects. |
| Viewport Selecting Enabled | Object is capable of being picked in viewport. |
| Select Script | Script to run when the object is picked in the viewport. See select scripts . |
| Cache Object Transform | Caches object transforms once Houdini calculates them. This is especially useful for objects whose world space position is expensive to calculate (such as Sticky objects), and objects at the end of long parenting chains (such as Bones). This option is turned on by default for Sticky and Bone objects. See the OBJ Caching section of the Houdini Preferences window for how to control the size of the object transform cache. |