Emboss compositing node

Adds a lighting effect to the image by using a bump map.

All Parameters Local variables Example files

See also: Bump, Lighting

Emboss is a simple lighting effect which uses a bump map to produce shadows and highlights. Both diffuse and specular colors can be used to light the image.

The position of the light determines where the highlights and shadows will occur, as well as the specular highlight. The X/Y position is in the UV space of the image (0-1), while Z is used to determine the distance of the light from the image (this only has an effect on the reflectivity of the image, and not the intensity of the light).

The bump plane can either be generated from the image itself, or Emboss can use a Bump plane connected to either input 1 or 2. The 'Bump Plane' parameter should contain the name of this plane. In the event that both input 1 and 2 contain a bump plane, the plane from input 2 takes priority. A bump plane can be generated using the Bump COP.

For more advanced lighting effects, the Lighting COP can be used.

Overloading VEX Parameters

This operator is implemented in VEX, which supports parameter overloading. If the first input has a plane which matches an operation parameter’s channel name, the input plane will be used as the parameter’s value, effectively overriding it. The overloaded parameter is then evaluated from the plane on a per-pixel basis.

eg. If the input COP has the following planes:

C{r,g,b}
A
fogdens
and it is fed into a VEX Fog COP, the fog density will be determined at each pixel by the fogdens plane, since the Fog Density parameter’s channel name matches the 'fogdens' channel name.

Scoping

This operation may be restricted to certain planes, or components of planes. In addition, the operation may be applied to a subset of frames within the sequence. An image must have both its frame and plane scoped to be modified.

Images that are not modified are passed through, which does not take any memory or processing time.

Masking

This operation may be masked, which restricts the operation to an area of the image. The mask may be inverted, brightened or dimmed.

The mask input is on the side of the node. The label on the connector indicates the plane being used as a mask.

The mask input can also be scaled to fit the output image’s resolution, if they differ. However, if this node changes more often than the mask input, it is faster to place a Scale COP in front of the mask input to do the resize, as the resize will not occur on every cook of this node.

Parameters

Emboss

Light Position

Positions the light relative to the image. (0.5, 0.5) is the center of the image (0 is the left or bottom, 1 is the right or top). The Z component determines how far the light is from the image, which affects how the light reflects off the bumps. The distance does not affect light intensity.

Diffuse Color

The color of the light.

Specular Color

Determines the color of all the specular highlights.

Diffuse Dimmer

Allows you to increase or decrease the diffuse contributions.

Specular Dimmer

Allows you to increase or decrease the specular contributions.

Bump Height

Higher bumps produce more noticeable shadows and highlights. This parameter affects both the auto-generated bump plane or the user-supplied bump plane.

Specular Model

Phong

A good specular model for metallic-looking specular effects.

Blinn

A good specular model for non-metallic specular effects.

Phong Exponent

The larger the exponent, the more defined the specular area becomes. Affects the Phong specular model only.

Blinn Roughness

Roughness describes the smoothness of the surface; smooth surfaces scatter light much less than rough ones. Increasing the roughness will increase the extent of specular highlights. Affects the Blinn specular model only.

Bump Plane

When supplying a bump plane to emboss through either the first input or the second input, you need to select the plane used as the bump plane.

Mask

A mask can be chosen to limit the effect of the operator to areas defined by the mask. The mask can be taken from the mask input (side input) or from the first input itself.

Effect Amount

If no mask is present, this blends the output with the input by a constant amount (0 = all input, 1 = all output).

If a mask is present, this amount multiplies the mask.

Operation Mask

Selects the mask plane to use as a mask from the mask input. The mask can be selected from:

A mask can be a component of a plane or an entire plane. If a vector plane is supplied as a mask, its components are multiplied by the images' components.

Scalar Mask ('A', 'C.r')

C.r = I.r * M
C.g = I.g * M
C.b = I.b * M

Vector Mask ('C')

C.r = I.r * M.r
C.g = I.g * M.g
C.b = I.b * M.b

First Input

Useful for masking the operation to the image’s own alpha plane.

Mask Input

Selects the mask from the side mask input.

Off

Turns off masking, without requiring disconnection of the mask input (useful for temporarily disabling the mask).

Resize Mask to Fit Image

If the mask image is a different resolution than the output image, turning on this parameter will scale the mask to the output image’s resolution.

If this node is changing constantly, and the mask is not, it is somewhat faster to put a Scale COP down to do the resize for the mask image. Otherwise, the scale will occur every time this node cooks.

Invert Mask

Inverts the mask so that all fully 'masked' portions become unmasked. This saves you from inserting an Invert COP after the node with the mask.

Scope

Plane Scope

Specifies the scope for both the RGB components of Color, Alpha, and other planes. The (C)RGBA mask only affects Color components and Alpha. 'C' will toggle all the RGB components.

For planes other than Color and Alpha, the plane name (plus component, if applicable) should be specified in the string field. The pulldown menu can be used to select planes or components present in this node.

A plane is specified by its name. A component is specified by both its plane and component name. The '*' wildcard may be used to scope all extra planes. Any number of planes or components can be specified, separated by spaces.

Examples:

P
N.x N.y
P N Pz

Frame Scope

Frame Scope

Allows scoping of specific frames in the frame range. This is in addition to the plane scope (so a plane at a certain frame must be both plane scoped and frame scoped to be modified).

All Frames

All frames are scoped.

Inside Range

All frames inside a subrange are scoped.

Outside Range

All frames outside a subrange are scoped.

Even Frames

Even numbered frames are scoped.

Odd Frames

Odd numbered frames are scoped.

Specific Frames

A user-defined list of frames are scoped.

Frame Range

For Inside/Outside range, this parameter specifies the subrange of the sequence to scope (or unscope). This can be edited in Timeline viewer mode ( Ctrl + 2 in viewer).

Frame Dropoff

For Inside/Outside Range, this parameter specifies certain number of frames before and after to slowly ramp up to scoped. The operation will be blended with its input to 'ease in' or 'ease out' the scoping effect over a number of frames. This can be edited in Timeline viewer mode ( Ctrl + 2 in viewer).

Non-scoped Effect

For unscoped frames, this sets the blend factor between the input and modified images. Normally this is zero (use the input image). By setting this to a non-zero value, you can make unscoped frames be 'slightly' unscoped. The value can vary between 0 (unscoped) and 1 (scoped).

Frame List

The frame list for 'Specific Frames'. Frame numbers should be separated by spaces.

Automatically Adjust for Length Changes

If the sequence range changes, enabling this parameter will adjust the subrange and frame dropoff lengths to fit the new range.

Local variables

L

Sequence length

S

Start of sequence

E

End of sequence

IL

Input sequence length

SR

Sequence frame rate

NP

Number of planes in sequence

W,H

Width and height of image

I

Image index (0 at start frame)

IT

Image time (0 at start frame)

AI

Current plane array index

PI

Current plane index

PC

Num of channels in current plane

CXRES

Composite Project X resolution

CYRES

Composite Project Y resolution

CPIXA

Composite Project pixel aspect ratio

CDEPTH

Composite Project raster depth

CBP

Composite Project black point

CWP

Composite Project white point

Example files

emboss

$HFS/houdini/help

Load | Launch

Embossing images with the Emboss COP.

Usages in other examples

Example name Example for