TG Image Lookup Noise Parameters

TG IMAGE LOOKUP NOISE

Noise Type
Noise Octaves
Noise Strength
Noise Steps
Noise Overall Scale
Noise x, y, z Scale
Animation : Frame Offset
Surface Colour 1 and Surface Colour 2
Use Image
V
Texture Image
Saturation
 

TG IMAGE LOOKUP NOISE PROJECTED

Accurate Screen Projection

TG IMAGE LOOKUP NOISE

Noise Type

Range : 1 to 3

1 is Perlin, 2 is Classic,and 3 is Sparse.

Noise Octaves

Range : 1 to 10

Higher values add more detail to the noise, but take longer to render. Note that values above 4 or 5 generally don’t show much of a visible increase in detail.

Noise Strength

Range : 0 to 100

Higher values give more effect from the noise, resulting in a more broken up and random look to the result.

Noise Steps

Range : 0 to 50

Controls the quantising of the noise result into a series of steps, which often show as “contours” in the result (rather like height contours, where noise of a particular value is assigned a particular colour).

Noise Overall Scale

Range : 0 to 1000

Higher values result in smaller, more dense pattern to the noise (high values are particularly good for giving stone like results). Note that higher values may result in slower rendering.

Noise x, y, z Scale

Range : 0 to 100, for each parameter

Control the scaling of the noise in the x, y and z directions independently, allowing the effect to be stretched and squashed.

Note that in order to allow the full range of values, due to the workings of ShaderLab 2.2, the parameter is displayed as a colour parameter, and has its initial values set to just above 1; also as a result, the parameter will allow negative values, which will scale the noise similarly but reverse the direction (negative values are not generally recommended though!).

Animation : Frame Offset

Range : 0 to 1, for each parameter

Sets an adjustment to the noise position, which alters automatically with each frame number (allows the noise effect to animate, without the need for any keyframing)

Surface Colour 1 and Surface Colour 2

Range : colour values

If the Use Image parameter is unchecked, then these two colour are used in place of reading from the image, with the quanitised noise value being used to mix between them.

Use Image

Range : Checked, Unchecked

When checked, the shader uses the selected image to lookup the end colour represented by any given noise value.

When unchecked, the shader uses the given noise value to blend between the two colours specified by Surface Colour 1 and Surface Colour 2.

V

Range : 0 to 1

When looking up the colour represented by a particular noise value, the shader reads along one line of the image, from left to right. The line of the image it reads from is controlled by V - at a value of 0, the shader reads from the top line of the image, at 0.5 it reads the middle line of the image, and at 1 it reads from the bottom line of the image.

Texture Image

Range : image

The image used to lookup the final colour represented by a given noise value. Note that the results do not look anything like the image! Instead, noise values from 0 to 1 represent how far along from left to right to read in order to look up the final colour to be used (with V specifying which line of the image is to be used).

This means images with smoothly varying colours will give smooth results, while those with sharp and sudden changes in colour will give a much more random and detailed look to the result. It’s best not to think of this as a texture map in the conventional sense, but instead as a list of colours that are used.

Saturation

Range : 0 to 50

Modifies the colour saturation of the final result.

Values of less than 1 will reduce the colour saturation (a value of zero giving a greyscale image), and values of greater than 1 will increase the colour saturation.

However, also bear in mind that quite often, a value above 1 in this parameter will be creating a colour that is “impossible” to render (eg red = 1025, where red can only vary from 0 to 255 on the display). The interpretation of these values in the final render may be somewhat unusual!

TG IMAGE LOOKUP NOISE PROJECTED

previous parameters as TG Image Lookup Noise

This shader works in the same way as TG Image Lookup Noise Projected, only the noise is projected based on the screen / final rendered image co-ords. The one new parameter is :

Accurate Screen Projection

Range : Checked, Unchecked

When checked, the projection from the screen / final render is exact. Object geometry, location, viewing angle etc will not change the result.

When unchecked, “incorrect” calculations are used for the screen / final render image projection. This gives an effect which is dependent upon the screen / final rendered image co-ords, but is still modified by the geometry of the object, and the viewing angle, viewing distance, etc - this can add some unusual variation into the look, as objects (or the camera) move around a scene.

TG Image Lookup Noise Intro

TG Image Lookup Noise Parameters

TG Toon Pack Index