GLSL TOP

From TouchDesigner Documentation
Jump to: navigation, search

Summary
[edit]

The GLSL TOP renders a GLSL shader into a TOP image. Use the Info DAT to check for compile errors in your shaders.

The GLSL TOP can act as a pixel shader, or the more general and complex Compute Shader. Caveat: Compute Shaders need GLSL 4.30 or later.

Refer to the Write a GLSL TOP article for more info on using this TOP.

The GLSL TOP has one docked compute shader as well as a normal GLSL shader. Change he Mode to Compute Shader. it will use the glsl1_compute DAT.

See the GLSL Category for more information, and Compute Shader.

PythonIcon.pngglslTOP_Class


Parameters - GLSL Page

GLSL Version glslversion - - Pick what version of GLSL to compile the shader with.

  • 1.20 glsl120 -
  • 3.30 glsl330 -
  • 4.00 glsl400 -
  • 4.10 glsl410 -
  • 4.20 glsl420 -
  • 4.30 glsl430 -
  • 4.40 glsl440 -
  • 4.50 glsl450 -
  • 4.60 glsl460 -

Mode mode - - Choose what type of shader you are writing, vertex/pixel shader, or a compute shader.

  • Vertex/Pixel Shader vertexpixel -
  • Compute Shader compute -

Preprocess Directives predat -  

Vertex Shader vertexdat - Points to the DAT holding the Vertex Shader. Drag & Drop a DAT here, or manually enter the path to the DAT.  

Pixel Shader pixeldat - Points to the DAT holding the Pixel Shader. Drag & Drop a DAT here, or manually enter the path to the DAT.  

Compute Shader computedat - Points to the DAT holding the Compute Shader. Drag & Drop a DAT here, or manually enter the path to the DAT.  

Load Uniform Names loaduniformnames - When this button is pressed the node will try to pre-fill all it's uniform parameter with uniforms that are declare in the shader. Note that the shader compiler will likely not expose uniforms that are unused.  

Dispatch Size dispatchsize - - The dispatch size to use when executing a compute shader.

  • X dispatchsizex -
  • Y dispatchsizey -
  • Z dispatchsizez -

Output Access outputaccess - - Controls how the output textures will be accessed. If the textures will be read from (such as using previous frame's values), then the access should be changed to Read-Write instead of Write Only.

  • Write Only writeonly -
  • Read Only readonly -
  • Read-Write readwrite -

Output Type type - - Specify what type of texture to create. When creating a 3D texture the TOP will render once for every slice of the output. Refer to 3D Textures and 2D Texture Arrays for more info.

  • 2D Texture texture2d - Creates a 2D texture.
  • 2D Texture Array texture2darray - Creates a 2D Texture Array. Slices of the array can be access using a non-normalized integer index for the w coordinate.
  • 3D Texture texture3d - Creates a 3D Texture. Slices of the array can be accessed using the w coordinate in the range 0-1. Value of the texture in between slices are interpolated.

Depth depth - - Set the depth of the 3D texture from the Input or the Custom Depth parameter.

  • Input input -
  • Custom custom -

Custom Depth customdepth - Manually set the depth of the 3D texture, otherwise it will use the depth of the input.  

Clear Outputs clearoutputs -  

Clear Value clearvalue - -

  • Clear Value clearvaluer -
  • Clear Value clearvalueg -
  • Clear Value clearvalueb -
  • Clear Value clearvaluea -

Input Mapping inputmapping - - Determines how the node's input(s) are passed into the shader for use when creating a 3D Texture. By default all of the inputs are passed to each slice. When using the N inputs per Slice mode, the first N inputs are passed to the first slice, the next N inputs are passed the second slice, and so on. When it runs out of inputs it loops back to the first input. N is selected by the parameter N Value.

  • All Inputs to Every Slice all -
  • N Input(s) per Slice ninputs -

N Value nval - Determines how many inputs are passed to the shader per slice when using the N inputs per Slice mode for Input Mapping. If for example this is set to 2, then the first 2 inputs will be passed to the first slice, the next 2 inputs will be passed the second slice, and so on. It will loop back to the start of the inputs if it runs out before it reaches the last slice.  

Input Extend Mode UV inputextenduv - - Controls what is returned from your texture sampling functions when the U and V texture coordinates (called S and T in the shader) are outside [0-1] range.

  • Hold hold -
  • Zero zero -
  • Repeat repeat -
  • Mirror mirror -

Input Extend Mode W inputextendw - - Controls what is returned from your texture sampling functions when the W texture coordinate (called W in the shader) are outside [0-1] range. Only useful for 3D Texture.

  • Hold hold -
  • Zero zero -
  • Repeat repeat -
  • Mirror mirror -

# of Color Buffers numcolorbufs - Any shader you write can output to more than one RGBA buffer at a time. Turn up this value to have more color buffers allocated for you, and refer to [Write_a_GLSL_TOP#Outputting_to_Multiple_Color_Buffers Write a GLSL TOP] for more information on using this feature.  


Parameters - Vectors Page

These are passed as uniforms into your shader. Depending on how the uniform is declared only some of the values of the 4 available per parameter as passes to the shader. For example, if the uniform is declared as a vec2, then only the first 2 values are passed to the shader, the other 2 are ignored.

Uniform Name 0 uniname0 - The uniform name, as declared in the shader  

Value value0 - - The value(s) to give the uniform.

  • Value value0x -
  • Value value0y -
  • Value value0z -
  • Value value0w -


Parameters - Arrays Page

CHOP Uniforms allow you to send CHOP channel data into a GLSL shader as an array. Depending on the array type used, the number of values you can send into the shader may be limited. If you are using Uniform Arrays, you can use the Built-In variable int(var('SYS_GFX_GLSL_MAX_UNIFORMS')) to get an idea of how many values you can pass to the shader. Current GPUs are vec4 based for uniform arrays, so the maximum array size is int(var('SYS_GFX_GLSL_MAX_UNIFORMS')) / 4. Other uniforms will take away from this maximum. If you are using Texture Buffers the maximum array size is far bigger, int(var('SYS_GFX_MAX_TEXTURE_BUFFER_SIZE')) will tell you the max for this. The max for texture buffer is per texture buffer, and having multiple texture buffers does not take away from the max for each array.

Uniform Name 0 chopuniname0 - The name of the uniform. You can send up to 4 channels into the GLSL shader in a single uniform. The number of channels is determined by the float/vec2/vec3/vec4 menu to the right of the name. For a CHOP with a single channel declare your uniform as a float, for one with two channels declare your uniform as a vec2, etc. The data is interleaved in the uniform. I.e the .x component is the 1st channel, .y is the 2nd channel, etc.  

Type chopunitype0 - - The data type of the uniform in the shader.

  • float float -
  • vec2 vec2 -
  • vec3 vec3 -
  • vec4 vec4 -

CHOP chop0 - The channels from this CHOP will be sent to the GLSL shader.  

Array Type choparraytype0 - - The type of the uniform.

  • Uniform Array uniformarray - All GPUs can send array data into a GLSL shader using Uniform Arrays.
  • Texture Buffer texturebuffer - Newer GPUs can send array data into a GLSL shader using Texture Buffers. Texture Buffers use texture memory and texture fetches to access the data, which allows them to store many more values.

Declare them:

uniform samplerBuffer <uniformname>;

And sample them like this

vec4 val = texelFetch(<uniformname>, i);

Where i is the 0-based index (an integer) into the buffer that you want to get a value for.


Parameters - Matrices Page

Uniform Name 0 matuniname0 - The name of the matrix uniform.  

Matrix matvalue0 - The value to assign the matrix. For valid ways to specify this, see the Matrix Parameters article.  


Parameters - Atomic Counters Page

Uniform Name 0 acname0 -  

Initial Value Type acinitval0 - - Specifies how the atomic counters receive their initial value, either through a single default value or a CHOP.

  • Single Value val -
  • CHOP Values chop -

Initial Value acsingleval0 - Specifies a single value that all atomic counters in this binding will be initialized to.  

Initial Values CHOP acchopval0 - A reference to the CHOP that will determine the initial values of the atomic counters in this binding. The CHOP will be spanned in track order, so the values from the first track will be read in order first, then the next track (if there is one) and so on. If there are more initial values to fill than there are values in the CHOP then they will all be set to 0. Atomic counters will be initialized from low to high offsets.  


Parameters - Common Page

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

  • Use Input useinput - Uses the input's resolution.
  • Eighth eighth - Multiply the input's resolution by that amount.
  • Quarter quarter - Multiply the input's resolution by that amount.
  • Half half - Multiply the input's resolution by that amount.
  • 2X 2x - Multiply the input's resolution by that amount.
  • 4X 4x - Multiply the input's resolution by that amount.
  • 8X 8x - Multiply the input's resolution by that amount.
  • Fit Resolution fit - Fits the width and height to the resolution given below, while maintaining the aspect ratio.
  • Limit Resolution limit - The width and height are limited to the resolution given below. If one of the dimensions exceeds the given resolution, the width and height will be reduced to fit inside the given limits while maintaining the aspect ratio.
  • Custom Resolution custom - Enables the Resolution parameter below, giving direct control over width and height.

Resolution resolution - - 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.

  • W resolutionw -
  • H resolutionh -

Resolution Menu resmenu - A drop-down menu with some commonly used resolutions.  

Use Global Res Multiplier resmult - 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.  

Output Aspect outputaspect - - Sets the image aspect ratio allowing any textures to be viewed in any size. Watch for unexpected results when compositing TOPs with different aspect ratios. (You can define images with non-square pixels using xres, yres, aspectx, aspecty where xres/yres != aspectx/aspecty.)

  • Use Input useinput - Uses the input's aspect ratio.
  • Resolution resolution - Uses the aspect of the image's defined resolution (ie 512x256 would be 2:1), whereby each pixel is square.
  • Custom Aspect custom - Lets you explicitly define a custom aspect ratio in the Aspect parameter below.

Aspect aspect - - Use when Output Aspect parameter is set to Custom Aspect.

  • Aspect1 aspect1 -
  • Aspect2 aspect2 -

Aspect Menu armenu - A drop-down menu with some commonly used aspect ratios.  

Input Smoothness inputfiltertype - - This controls pixel filtering on the input image of the TOP.

  • Nearest Pixel nearest - Uses nearest pixel or accurate image representation. Images will look jaggy when viewing at any zoom level other than Native Resolution.
  • Interpolate Pixels linear - 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 mipmap - Uses mipmap filtering when scaling images. This can be used to reduce artifacts and sparkling in moving/scaling images that have lots of detail.

Fill Viewer fillmode - - Determine how the TOP image is displayed in the viewer. NOTE:To get an understanding of how TOPs work 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.

  • Use Input useinput - Uses the same Fill Viewer settings as it's input.
  • Fill fill - Stretches the image to fit the edges of the viewer.
  • Fit Horizontal width - Stretches image to fit viewer horizontally.
  • Fit Vertical height - Stretches image to fit viewer vertically.
  • Fit Best best - Stretches or squashes image so no part of image is cropped.
  • Fit Outside outside - 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 nativeres - Displays the native resolution of the image in the viewer.

Viewer Smoothness filtertype - - This controls pixel filtering in the viewers.

  • Nearest Pixel nearest - Uses nearest pixel or accurate image representation. Images will look jaggy when viewing at any zoom level other than Native Resolution.
  • Interpolate Pixels linear - Uses linear filtering between pixels. Use this to 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 mipmap - Uses mipmap filtering when scaling images. This can be used to reduce artifacts and sparkling in moving/scaling images that have lots of detail.

Passes npasses - Duplicates the operation of the TOP the specified number of times. Making this larger than 1 is essentially the same as taking the output from each pass, and passing it into the first input of the node and repeating the process. Other inputs and parameters remain the same for each pass.  

Channel Mask chanmask - Allows you to choose which channels (R, G, B, or A) the TOP will operate on. All channels are selected by default.  

Pixel Format 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.

  • Use Input useinput - Uses the input's pixel format.
  • 8-bit fixed (RGBA) rgba8fixed - Uses 8-bit integer values for each channel.
  • sRGB 8-bit fixed (RGBA) srgba8fixed - Uses 8-bit integer values for each channel and stores color in sRGB colorspace.
  • 16-bit float (RGBA) rgba16float - Uses 16-bits per color channel, 64-bits per pixel.
  • 32-bit float (RGBA) rgba32float - Uses 32-bits per color channel, 128-bits per pixels.
  • 10-bit RGB, 2-bit Alpha, fixed (RGBA) rgb10a2fixed - Uses 10-bits per color channel and 2-bits for alpha, 32-bits total per pixel.
  • 16-bit fixed (RGBA) rgba16fixed - Uses 16-bits per color channel, 64-bits total per pixel.
  • 11-bit float (RGB), Positive Values Only rgba11float - 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).
  • 16-bit float (RGB) rgb16float -
  • 32-bit float (RGB) rgb32float -
  • 8-bit fixed (Mono) mono8fixed - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 8-bits per pixel.
  • 16-bit fixed (Mono) mono16fixed - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 16-bits per pixel.
  • 16-bit float (Mono) mono16float - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 16-bits per pixel.
  • 32-bit float (Mono) mono32float - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 32-bits per pixel.
  • 8-bit fixed (RG) rg8fixed - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 8-bits per channel, 16-bits total per pixel.
  • 16-bit fixed (RG) rg16fixed - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 16-bits per channel, 32-bits total per pixel.
  • 16-bit float (RG) rg16float - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 16-bits per channel, 32-bits total per pixel.
  • 32-bit float (RG) rg32float - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 32-bits per channel, 64-bits total per pixel.
  • 8-bit fixed (A) a8fixed - An Alpha only format that has 8-bits per channel, 8-bits per pixel.
  • 16-bit fixed (A) a16fixed - An Alpha only format that has 16-bits per channel, 16-bits per pixel.
  • 16-bit float (A) a16float - An Alpha only format that has 16-bits per channel, 16-bits per pixel.
  • 32-bit float (A) a32float - An Alpha only format that has 32-bits per channel, 32-bits per pixel.
  • 8-bit fixed (Mono+Alpha) monoalpha8fixed - A 2 channel format, one value for RGB and one value for Alpha. 8-bits per channel, 16-bits per pixel.
  • 16-bit fixed (Mono+Alpha) monoalpha16fixed - A 2 channel format, one value for RGB and one value for Alpha. 16-bits per channel, 32-bits per pixel.
  • 16-bit float (Mono+Alpha) monoalpha16float - A 2 channel format, one value for RGB and one value for Alpha. 16-bits per channel, 32-bits per pixel.
  • 32-bit float (Mono+Alpha) monoalpha32float - A 2 channel format, one value for RGB and one value for Alpha. 32-bits per channel, 64-bits per pixel.


Operator Inputs

  • Input 0 -
  • Input 1 -
  • Input 2 -

TouchDesigner Build:

TOPs
Add • Anti Alias • Blob Track • Blur • Buffer Select • Cache Select • Cache • Channel Mix • CHOP to • Experimental:CHOP to • Chroma Key • Circle • Experimental:Circle • Composite • Constant • Experimental:Constant • Convolve • Corner Pin • CPlusPlus • Crop • Cross • Cube Map • Depth • Difference • DirectX In • DirectX Out • Displace • Edge • Emboss • Feedback • Fit • Flip • Function • GLSL Multi • GLSL • HSV Adjust • HSV to RGB • Import Select • In • Inside • Introduction To TOPs id • Kinect Azure Select • Kinect Azure • Kinect • Layout • Leap Motion • Experimental:Lens Distort • Level • Limit • Lookup • Experimental:Lookup • Luma Blur • Luma Level • Math • Matte • Mirror • Monochrome • Movie File In • Movie File Out • Experimental:Movie File Out • Multiply • NDI In • Experimental:NDI In • NDI Out • Noise • Normal Map • Notch • Null • Nvidia Flex • Nvidia Flow • Oculus Rift • OP Viewer • OpenColorIO • OpenVR • Ouster Select • Ouster • Out • Outside • Over • Pack • Photoshop In • Point File In • Point File Select • Experimental:Point Transform • PreFilter Map • Projection • Ramp • Experimental:Ramp • RealSense • Experimental:RealSense • Rectangle • Experimental:Rectangle • Remap • Render Pass • Render Select • Render • Reorder • Resolution • RGB Key • RGB to HSV • Scalable Display • Screen Grab • Experimental:Screen Grab • Screen • Script • Select • Shared Mem In • Shared Mem Out • Slope • SSAO • Stype • Substance Select • Substance • Subtract • SVG • Switch • Syphon Spout In • Syphon Spout Out • Text • Experimental:Text • Texture 3D • Texture Sampling arameters • Threshold • Tile • Time Machine • TOP • TOP iewer • Touch In • Touch Out • Transform • Under • Video Device In • Video Device Out • Video Stream In • Experimental:Video Stream In • Video Stream Out • Experimental:Video Stream Out • Vioso • Web Render • ZED

An Operator Family that creates, composites and modifies images, and reads/writes images and movies to/from files and the network. TOPs run on the graphics card's GPU.

An Operator Family that manipulates text strings: multi-line text or tables. Multi-line text is often a command Script, but can be any multi-line text. Tables are rows and columns of cells, each containing a text string.

The OpenGL code that creates a rendered image from polygons and textures. Shaders can be made of up to three parts: Vertex Shader, Geometry Shader and/or Pixel Shader, which are either embedded inside Materials, or placed in Text DATs and referenced to a GLSL Material.

A sequence of vertices form a Polygon in a SOP. Each vertex is an integer index into the Point List, and each Point holds an XYZ position and attributes like Normals and Texture Coordinates.

An Operator Family which operate on Channels (a series of numbers) which are used for animation, audio, mathematics, simulation, logic, UI construction, and many other applications.

The width and height of an image in pixels. Most TOPs, like the Movie File In TOP can set the image resolution. See Aspect Ratio for the width/height ratio of an image, taking into account non-square pixels.

The viewer of a node can be (1) the interior of a node (the Node Viewer), (2) a floating window (RMB->View... on node), or (3) a Pane that graphically shows the results of an operator.

A CHOP outputs one or more channels, where a channel is simply a sequence of numbers, representing motion, audio, etc. Channels are passed between CHOPs in TouchDesigner networks. See also Export.