Ramp TOP

From TouchDesigner 088 Wiki

RampTOP 02.jpg

Summary

The Ramp TOP allows you to interactively create vertical, horizontal, radial, and circular ramps. Using the ramp bar and the color picker, you can add as many color tabs to the ramp as you like, each with its own color and alpha values. Click on a color tab to select it and change its color. Click elsewhere on the ramp bar to add another color keyframe. Drag a color tab off the ramp bar to delete it.

The data for each color keyframe in the ramp is held in the DAT specified by the DAT parameter. Each row in this DAT (in Table Format) represents a color keyframe entry in the ramp. The first column is the color keyframe's position on the ramp, the range is 0-1. The next 4 columns are the RGBA value for the color keyframe at that position. The DAT can be edited directly and the ramp will update in real-time.

PythonIcon.png rampTOP_Class

Parameters - Ramp Page

DAT /dat - specifies the DAT which defines the entries in the ramp.

Color /color - The color and alpha of each ramp keyframe can be set here. Select between an HSV or RGB colorpicker, or click the "+" button to open a color dialog box with predefined colors.

Type /type - The type of ramp, choose between vertical, horizontal, radial, and circular.

Position /position - Sets the center point for radial and circular ramps.

Phase /phase - Offsets the beginning of the ramp.

Period /period - Adjusts the length of the ramp, similar to a UV scaling.

Extend Left/Right /extendleft /extendright - sets the extend (or repeat) conditions of the ramp beyond the defined range. This parameter determines what happens at the edges of the ramp.

  • Hold - The pixel values past the left/right edges of the ramp continue to extend past that edge.
  • Black - The pixel values past the left/right edges of the ramp are black (RGBA = 0,0,0,1).
  • Zero - The pixel values past the left/right edges of the ramp are zero (RGBA = 0,0,0,0).
  • Repeat - The image is repeated past the left/right edges of the ramp.
  • Mirror - The image is mirrored past the left/right edges of the ramp.

Interpolate Notches /interp - Change type of interpolation between the color keyframes in the ramp.

  • Step - no interpolation, ramp steps from value to value.
  • Linear - linear interpolation between keyframes.
  • Ease-in, Ease-out - Ease in/out interpolation between keyframes.
  • Hermite - Hermite interpolation between keyframes.

Curve Tension /tension - Only enabled when using Hermite interpolation. Adjusts the tension bias of the Hermite curve used for interpolation.

Anti-Alias /antialias - Sets level of anti-aliasing for Radial and Circular type ramps.

Fit Aspect /fitaspect - Adjusts the fit of Radial and Circular type ramps based on aspect ratio.

Dither /dither - dithers the ramp to help deal with banding and other artifacts created by precision limitations.

Multiply RGB by Alpha /multrgbbyalpha - Premultiplies the image.

Parameters - Common Page

Resolution - quickly change the resolution of the TOP's data.

  • Input - uses the input's resolution.
  • Eighth, Quarter, Half, 2X, 4X, 8X - multiply the input's resolution by that amount.
  • Custom Resolution - enables the Custom Res parameter below, giving direct control over res in the X and Y axis.

Custom Res - enabled only when the Resolution parameter is set to Custom Resolution. Some Generators like Constant and Ramp do not use inputs and only use this field to determine their size. The drop down menu on the right provides some commonly used resolutions.

Use Global Resolution Multiplier - Uses the Global Resolution Multiplier found in Edit>Preferences>TOPs. This multiplies all the TOPs resolutions by the set amount. This is handy when working on computers with different hardware specifications. If a project is designed on a desktop workstation with lots of graphics memory, a user on a laptop with only 64MB VRAM can set the Global Resolution Multiplier to a value of half or quarter so it runs at an acceptable speed. By checking this checkbox on, this TOP is affected by the global multiplier.

Aspect Ratio - sets the image aspect ratio, which is the visible width vs height, independent of the pixel resolution. If the pixels are not square, the aspect ratio is not the resolution's width/height. Watch for unexpected results when compositing TOPs with different aspect ratios.

  • Input - uses the input's aspect ratio.
  • Resolution - uses the aspect of the image's defined resolution (ie 512x256 would be 2:1), whereby each pixel is square.
  • Custom Aspect Ratio - lets you explicitly define a custom aspect ratio.

Fill Viewer - determine how the TOP image is displayed in the viewer.

  • Input - uses the same Fill Viewer settings as it's input.
  • Fill - stretches the image to fit the edges of the viewer.
  • Fit Horizontal - stretches image to fit viewer horizontally.
  • Fit Vertical - stretches image to fit viewer vertically.
  • Fit Best - stretches or squashes image so no part of image is cropped.
  • Fit Worst - stretches or squashes image so image fills viewer while constraining it's proportions. This often leads to part of image getting cropped by viewer.
  • Native Resolution - displays the native resolution of the image in the viewer.

NOTE: To get an understanding of how TOPs works with images, you will want to set this to Native Resolution as you lay down TOPs when starting out. This will let you see what is actually happening without any automatic viewer resizing.

Viewer Smoothness - This controls pixel filtering in the viewers.

  • Nearest Pixel - uses nearest pixel or accurate image representation. Images will look jaggy when viewing at any zoom level other than Native Resolution.
  • Interpolate Pixels - uses linear filtering between pixels. This is how you get TOP images in viewers to look good at various zoom levels, especially useful when using any Fill Viewer setting other than Native Resolution.
  • Mipmap Pixels - uses mipmapfiltering when scaling images. This can be used to reduce artifacts and sparkling in moving/scaling images that have lots of detail. When the input is 32-bit float format nearest filtering will always be used, regardless of what is selected in the menu.

Pixel Format - format used to store data for each channel in the image (ie. R, G, B, and A). Refer to Pixel Formats for more information.

  • Input - uses the input's pixel format.
  • 8-bit fixed (RGBA) - uses 8-bit integer values for each channel.
  • 16-bit float (RGBA) - uses 16-bits per color channel, 64-bits per pixel.
  • 32-bit float (RGBA) - uses 32-bits per color channel, 128-bits per pixels.


  • 10-bit RGB, 2-bit Alpha, fixed (RGBA) - uses 10-bits per color channel and 2-bits for alpha, 32-bits total per pixel.
  • 16-bit fixed (RGBA) - uses 16-bits per color channel, 64-bits total per pixel.
  • 11-bit float (RGB), Positive Values Only - A RGB floating point format that has 11 bits for the Red and Green channels, and 10-bits for the Blue Channel, 32-bits total per pixel (therefore the same memory usage as 8-bit RGBA). The Alpha channel in this format will always be 1. Values can go above one, but can't be negative. ie. the range is [0, infinite).
  • 8-bit fixed (R) - has 8-bits for the red channel, 8-bits total per pixel.
  • 16-bit fixed (R) - has 16-bits for the red channel, 16-bits total per pixel.
  • 16-bit float (R) - has 16-bits for the red channel, 16-bits per pixel.
  • 32-bit float (R) - has 32-bits for the red channel, 32-bits per pixel.
  • 8-bit fixed (RG) - has 8-bits for the red and green channels, 16-bits total per pixel.
  • 16-bit fixed (RG) - has 16-bits for the red and green channels, 32-bits total per pixel.
  • 16-bit float (RG) - has 16-bits for the red and green channels, 32-bits per pixel.
  • 32-bit float (RG) - has 32-bits for the red and green channels, 64-bits per pixel.
  • 8-bit fixed (A) - An Alpha only format that has 8-bits per channel, 8-bits per pixel.
  • 16-bit float (A) - An Alpha only format that has 16-bits per channel, 16-bits per pixel.
  • 32-bit float (A) - An Alpha only format that has 32-bits per channel, 32-bits per pixel.