Houdini is a high-end 3D animation package developed by Side Effects Software. It is often preferred over competing packages, such as Maya or XSI, for pure visual effects tasks, as opposed to character animation. Like Maya, Houdini is an open-environment and uses the popular Tcl/Tk scripting language and toolkit (as opposed to the proprietary MEL used in Maya). Houdini also has its own CShell-like scripting language, Hscript. However, any major scripting languages which support socket communication can interface with Houdini. Houdini primary distinction from other packages is that it has been designed as a purely procedural environment. The rewrite of this article is being devised at Talk:3D computer graphics/Temp. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Softimage|XSI is a high-end three-dimensional (3D) graphics application developed by Softimage, Co. ... Visual effects (vfx) is the term given to a sub-category of special effects in which images or film frames are created or manipulated for film and video. ... Character animation is a special aspect of the animation process, in which life is breathed into an artificial character. ... // Tcl (originally from Tool Command Language, but nonetheless conventionally rendered as Tcl rather than TCL; and pronounced like tickle) is a scripting language created by John Ousterhout. ... In computing, Tk is an open source, cross-platform widget toolkit, that is, a library of basic elements for building a graphical user interface (GUI). ... HScript is an abbreviation for Houdini Script, which is used in Sidefxs Houdini. ... Procedural, as an adjective, refers to the concept of procedure. ...

Digital assets are generally constructed by connecting sequences of operations (or OPs). This proceduralism has several advantages: it allows users to construct highly detailed geometric or organic objects in comparatively very few steps compared to other packages; it enables and encourages non-linear development; and new operators can be created in terms of existing operators, a flexible alternative to non-procedural scripting often relied on in other packages for customisation. Houdini uses this procedural paradigm throughout: for textures, shaders, particles, "channel data" (data used to drive animation), rendering and compositing. Since the late 1960s, the word paradigm (IPA: ) has referred to a thought pattern in any scientific discipline or other epistemological context. ... This article or section needs a complete rewrite for the reasons listed on the talk page. ... This article or section may be confusing for some readers, and should be edited to be clearer or more simplified. ... For more background on this topic, see game physics. ... Rendering is the process of generating an image from a model, by means of a software program. ... In visual effects post-production, compositing refers to creating complex images or moving images by combining images from different sources - such as real-world digital video, digitized film, synthetic 3-D imagery, 2-D animations, painted backdrops, digital still photographs, and text. ...

Houdini's operator-based structure is divided into several main groups:

• SOPs - surface operators.
• POPs - particle operators.
• CHOPs - channel operators.
• COPs - composite operators.
• DOPs - dynamic operators.
• ROPs - render operators.
• VOPs - VEX operators

Operators are connected together in networks. Data flows through, manipulated by each operator in turn. This data could represent 3D geometry, bitmap images, particles, dynamics, shader algorithms, animation, audio, or a combination of these. The paradigm is similar to that employed in node-based compositors such as Shake or Nuke. Table of Geometry, from the 1728 Cyclopaedia. ... For the use of the term raster in radio regulation, see frequency raster. ... In physics, dynamics is the branch of classical mechanics that is concerned with the effects of forces on the motion of objects. ... This article or section may be confusing for some readers, and should be edited to be clearer or more simplified. ... Flowcharts are often used to graphically represent algorithms. ... 12 frames per second is the typical rate for an animated cartoon. ... A schematic representation of hearing. ... Movable metal type Typesetting involves the presentation of textual material in an aesthetic form on paper or some other media. ... Shake is an image compositing package used in the post-production industry. ... Nuke is the Academy Award-winning compositing software used by Digital Domain. ...

Complex networks can be grouped into a single meta-operator nodes, allowing users to create their own sophisticated tools without the need for programming. These nodes can be regarded as a visual programming language made more interactive and accessible to artists.

Houdini is unique in its very rich set of tools, which are usually implemented as operators. This has lead to a higher learning curve than other comparable tools. Also unique to Houdini is the range of I/O OPs available to animators, including MIDI devices, raw files or TCP connections, audio devices (including built-in phoneme and pitch detection), mouse cursor position, and so on. Of particular note is Houdini's unique ability to work with audio, including sound and music synthesis and spatial 3D sound processing tools. These operators exist in the context called "CHOPs" for which Side Effects won a Technical Achievement Academy Award in 2002. In computing, Input/output, or I/O, is the collection of interfaces that different functional units (sub-systems) of an information processing system use to communicate with each other, or the signals (information) sent through those interfaces. ... Musical Instrument Digital Interface, or MIDI, is a system designed to transmit information between electronic musical instruments. ... The Transmission Control Protocol (TCP) is one of the core protocols of the Internet protocol suite. ... In human language, a phoneme is a set of phones (speech sounds or sign elements) that are cognitively equivalent. ... In music, pitch is the psychological correlate of the fundamental frequency of a note. ... Operating a mechanical mouse. ... A typical arrow-like mouse cursor. ...

VEX (Vector Expression) is one of Houdini's internal languages. It is similar to the RenderMan shading language. Using VEX a user can develop custom SOPs, POPs, shaders, etc. The current implementation of VEX utilizes SIMD style processing. RenderMan is an API developed by Pixar Animation Studios to describe three dimensional scenes and turn them into digital photorealistic images. ... -1...

Historically, Houdini's main strength has been its particle animation system, and its major weakness its unintuitive animation tools. As a result, its use was relegated to special effects. However, in more recent versions these tools have been vastly improved and it has been used in the various feature animation productions, such as The Wild, a major Disney feature film as well as the feature animation Ant Bully. The Wild is a computer-animated film directed by Steven Spaz Williams, produced by Clint Goldman, assistant produced by John Burton and C.O.R.E. Feature Animation, and was released by Walt Disney Pictures on April 14, 2006 (May 26, 2006 in UK). ... The Walt Disney Company (most commonly known as Disney) (NYSE: DIS) is one of the largest media and entertainment corporations in the world. ... Ant Bully is a computer-generated imagery (CGI) animated film that is based on John Nickles book of the same name. ...

Derivative

Derivative Inc. is a spin-off of Side Effects Software that markets a derivative of Houdini called TouchDesigner. Tailored toward real-time OpenGL-generated animation, it was used on rock group Rush's 30th Year Anniversary Tour to produce dynamic graphics driven directly by the musicians. OpenGL (Open Graphics Library) is a standard specification defining a cross-language cross-platform API for writing applications that produce 3D computer graphics (and 2D computer graphics as well). ... Rush is a Canadian progressive rock band comprising bassist, keyboardist and vocalist Geddy Lee, guitarist Alex Lifeson, and drummer and lyricist Neil Peart. ...

Version release history

• 8.1: June 2006 [1]
• 8.0: October 2005 [2]
• 7.0: September 2004 [3]
• 6.0: May 2003 [4]
• 5.5: May 2002 [5]

2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... For album titles with the same name, see 2002 (album). ...

External links

• Side Effects Software, Makers of Houdini
• Derivative Inc., spin-off of Side Effects Software and maker of TouchDesigner.
• Houdini artist community site