Editing POV-Ray (section)

==Features==
[[Image:Glasses 800 edit.png|thumb|Glass scene rendered by POV-Ray demonstrating [[Radiosity (computer graphics)|radiosity]], [[photon mapping]], [[focal blur]], and other photorealistic capabilities (image created by [[Gilles Tran]])]]

POV-Ray has matured substantially since it was created. Recent versions of the software include the following features:

* a [[Turing-completeness|Turing-complete]] scene description language (SDL) that supports macros and loops<ref>[http://paulbourke.net/geometry/supershape/ Paul Bourke: Supershape in 3D] are examples of POV-Ray images made with very short code</ref>
* a library of ready-made scenes, textures, and objects
* support for a number of [[geometric primitive]]s and [[constructive solid geometry]]
* several kinds of [[light source]]s
* atmospheric effects such as [[fog]] and ''media'' ([[smoke]], [[clouds]])
* [[Reflection (physics)|reflection]]s, [[refraction]]s, and light [[caustic (optics)|caustics]] using [[photon mapping]]
* surface patterns such as [[wrinkle]]s, bumps, and [[Capillary wave|ripples]], for use in [[procedural texture]]s and [[bump mapping]]
* [[Radiosity (computer graphics)|radiosity]]
* support for [[Texture (computer graphics)|textures]] and rendered output in many image formats, including [[Truevision Targa file format|TGA]], [[Portable Network Graphics|PNG]], and [[JPEG]], among others
* extensive [[user documentation]]
* support for custom output resolutions<ref>{{Cite web |title=POV-Ray: Documentation: 2.1.2.2 General Output Options |url=https://www.povray.org/documentation/view/3.6.0/217/ |access-date=2023-09-08 |website=www.povray.org}}</ref> (This includes extreme resolutions such as [[16K resolution|16K]])
* two types of [[Supersampling|SSAA]]<ref name=":0">{{Cite web |title=POV-Ray: Documentation: 2.1.2.8 Tracing Options |url=http://www.povray.org/documentation/view/3.6.2/223/ |access-date=2023-09-08 |website=www.povray.org}}</ref> Type 1 is an adaptive, non-recursive, super-sampling method. It is ''adaptive'' because not every pixel is super-sampled. Type 2 is an adaptive and recursive super-sampling method. It is ''recursive'' because the pixel is sub-divided and sub-sub-divided recursively. The ''adaptive'' nature of type 2 is the variable depth of recursion.<ref name=":0" />

One of POV-Ray's main attractions is its large collection of third-party-made assets and tools. A large number of tools, textures, models, scenes, and tutorials can be found on the web. It is also a useful reference for those wanting to learn how [[ray tracing (graphics)|ray tracing]] and related 3D geometry and computer graphics algorithms work.

===Current version===
The current official version of POV-Ray is 3.7. This version introduces:

* support for [[symmetric multiprocessing]] (SMP), to allow the renderer to take advantage of [[Multiprocessing|multiple processors]]
* support for [[high-dynamic-range imaging]] (HDRI), including the [[OpenEXR]] and [[Radiance (software)|radiance]] file formats
* improved [[Bounding volume|bounding]] using [[Binary space partitioning|BSP]] trees

Some of the main introduced features of the previous release (3.6) are:

* extending [[UV mapping]] to more primitives
* adding 16- and 32-bit integer data to a density file
* improving [[64-bit computing|64-bit]] [[computer compatibility|compatibility]]

In July 2006, [[Intel Corporation]] started using the [[beta version]] of 3.7 to demonstrate their new [[dual-core]] [[Conroe (microprocessor)|Conroe processor]] due to the efficiency of the SMP (symmetric multiprocessing) implementation.

===Primitives===
[[File:Venn 0000 0001 0001 0110.png|thumb|Rendering of the [[Venn diagram]] of four spheres created with [[constructive solid geometry]], or CSG. The source is [[commons:File:Venn 0000 0001 0001 0110.png#POV-Ray source|on the description page]] of the image.]]
[[Image:PNG transparency demonstration 1.png|thumb|Some colored [[dice]] rendered in POV-Ray. [[Constructive solid geometry|CSG]], [[refraction]] and [[focal blur]] are demonstrated.]]
POV-Ray, in addition to standard [[3d geometry|3D geometric]] shapes like [[torus|tori]], [[sphere]]s, and [[heightfield]]s, supports mathematically defined ''[[Primitives (computer graphics)|primitives]]'' such as the [[isosurface]] (a finite approximation of an arbitrary function), the [[polynomial]] primitive (an [[Infinity|infinite]] object defined by a [[Degree of a polynomial|15th order or lower polynomial]]), the [[julia set|julia fractal]] (a 3-dimensional slice of a [[Four-dimensional space|4-dimensional]] fractal), the [[superellipse|superquadratic ellipsoid]] (an intermediate between a sphere and a cube), and the [[parametric feature based modeler|parametric]] primitive (using equations that represent its surface, rather than its interior).

POV-Ray internally represents objects using their mathematical definitions; all POV-Ray primitive objects can be described by [[mathematical functions]]. This is different from many computer programs that include 3D models, which typically use [[triangle]] [[polygon mesh|mesh]]es to compose all the objects in a scene.

This fact provides POV-Ray with several advantages and disadvantages over other rendering and modeling systems; POV-Ray primitives are more accurate than their polygonal counterparts: objects that can be described in terms of spheres, planar surfaces, cylinders, tori, and the like, are perfectly smooth and mathematically accurate in POV-Ray renderings, whereas polygonal ''artifacts'' may be visible in mesh-based modeling software. POV-Ray primitives are also simpler to define than most of their polygonal counterparts, e.g., in POV-Ray, a [[sphere]] is described simply by its center and radius; in a mesh-based environment, a sphere must be described by a multitude of small connected polygons (usually [[UV sphere|quads]] or [[Icosphere|triangles]]).

On the other hand, script-based primitive modeling is not always a practical method to create certain objects, such as realistic characters or complex man-made artifacts like cars. Those objects can be created first in mesh-based modeling applications such as [[Wings 3D]] and [[Blender (software)|Blender]], and then they can be converted to POV-Ray's own mesh format.

===Examples of the scene description language===
The following is an example of the scene description language used by POV-Ray to describe a scene to render. It demonstrates the use of a background colour, camera, lights, a simple box shape having a surface normal and finish, and the transforming effects of rotation.

[[Image:I example povray scene rendering.png|thumb|right|POV-Ray image output based on the script]]

<syntaxhighlight lang="pov">
 #version 3.6;
// Includes a separate file defining a number of common colours
 #include "colors.inc"
 global_settings { assumed_gamma 1.0 }

// Sets a background colour for the image (dark grey)
 background   { color rgb <0.25, 0.25, 0.25> }

// Places a camera
// direction: Sets, among other things, the field of view of the camera
// right: Sets the aspect ratio of the image
// look_at: Tells the camera where to look
 camera       { location  <0.0, 0.5, -4.0>
                direction 1.5*z
                right     x*image_width/image_height
                look_at   <0.0, 0.0, 0.0> }

// Places a light source
// color: Sets the color of the light source (white)
// translate: Moves the light source to a desired location
 light_source { <0, 0, 0>
                color rgb <1, 1, 1>
                translate <-5, 5, -5> }
// Places another light source
// color: Sets the color of the light source (dark grey)
// translate: Moves the light source to a desired location
 light_source { <0, 0, 0>
                color rgb <0.25, 0.25, 0.25>
                translate <6, -6, -6> }

// Sets a box
// pigment: Sets a color for the box ("Red" as defined in "colors.inc")
// finish: Sets how the surface of the box reflects light
// normal: Sets a bumpiness for the box using the "agate" in-built model
// rotate: Rotates the box
 box          { <-0.5, -0.5, -0.5>,
                <0.5, 0.5, 0.5>
                texture { pigment { color Red }
                          finish  { specular 0.6 }
                          normal  { agate 0.25 scale 1/2 }
                        }
                rotate <45,46,47> }
</syntaxhighlight>

The following script fragment shows the use of variable declaration, assignment, comparison and the while loop construct:

[[Image:I example povray scene rendering2.png|thumb|right|POV-Ray image output based on the script]]

<syntaxhighlight lang="pov">
 #declare the_angle = 0;

 #while (the_angle < 360)
 	box {   <-0.5, -0.5, -0.5>
 		<0.5, 0.5, 0.5>
                texture { pigment { color Red }
                          finish  { specular 0.6 }
                          normal  { agate 0.25 scale 1/2 } }
 		rotate the_angle }
 	#declare the_angle = the_angle + 45;
 #end
</syntaxhighlight>