Rendering or image synthesis is the process of generating a photorealistic or non-photorealistic image from a 2D or 3D model by means of a computer program.[citation needed] The resulting image is referred to as the render. Multiple models can be defined in a scene file containing objects in a strictly defined language or data structure. The scene file contains geometry, viewpoint, texture, lighting, and shading information describing the virtual scene. The data contained in the scene file is then passed to a rendering program to be processed and output to a digital image or raster graphics image file. The term “rendering” is analogous to the concept of an artist’s impression of a scene. The term “rendering” is also used to describe the process of calculating effects in a video editing program to produce the final video output.

In rendering of 3D models, triangles and polygons in space might be primitives. In the case of 3D graphics, scenes can be pre-rendered or generated in realtime. Pre-rendering is a slow, computationally intensive process that is typically used for movie creation, where scenes can be generated ahead of time, while real-time rendering is often done for 3D video games and other applications that must dynamically create scenes. Though it receives less attention, an understanding of human visual perception is valuable to rendering. This is mainly because image displays and human perception have restricted ranges. A renderer can simulate a wide range of light brightness and color, but current displays – movie screen, computer monitor, etc. – cannot handle so much, and something must be discarded or compressed.

The optical basis of the simulation is that some diffused light from a given point on a given surface is reflected in a large spectrum of directions and illuminates the area around it. In English, many past and present participles of verbs can be used as adjectives. This is a slow process, but earnest hearts and united minds will render it a sure one. But time and history will render an unambiguous verdict on this matter, as Rubio shall soon see.

In distribution ray tracing, at each point of intersection, multiple rays may be spawned. In path tracing, however, only a single ray or none is fired at each intersection, utilizing the statistical nature of Monte Carlo experiments. Many rendering algorithms have been researched, and software used for rendering may employ a number of different techniques to obtain a final image.

  1. The rendering equation does not account for all lighting phenomena, but instead acts as a general lighting model for computer-generated imagery.
  2. These examples are programmatically compiled from various online sources to illustrate current usage of the word ‘render.’ Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
  3. A more sophisticated method is to modify the color value by an illumination factor, but without calculating the relationship to a simulated light source.
  4. Pre-rendering is a slow, computationally intensive process that is typically used for movie creation, where scenes can be generated ahead of time, while real-time rendering is often done for 3D video games and other applications that must dynamically create scenes.

An important distinction is between image order algorithms, which iterate over pixels of the image plane, and object order algorithms, which iterate over objects in the scene. For simple scenes, object order is usually more efficient, as there are fewer objects than pixels. Because of this, radiosity is a prime component of leading real-time rendering methods, and has been used from beginning-to-end to create a large number of well-known recent feature-length animated 3D-cartoon films. Radiosity is a method which attempts to simulate the way in which directly illuminated surfaces act as indirect light sources that illuminate other surfaces. This produces more realistic shading and seems to better capture the ‘ambience’ of an indoor scene.

OnLeaks has an excellent track record with making accurate early renders, especially for Pixel devices. The venerable leaker has produced renders for the Pixel 6 and Pixel 6 Pro with new details and specs. In his role at Microsoft, Frédéric Dubut exemplified these qualities and greatly contributed to the industry’s understanding of how Bing crawls, indexes, renders and ranks. Rendering for movies often takes place on a network of tightly connected computers known as a render farm. Rendering research is concerned with both the adaptation of scientific models and their efficient application. For real-time, it is appropriate to simplify one or more common approximations, and tune to the exact parameters of the scenery in question, which is also tuned to the agreed parameters to get the most ‘bang for the buck’.


Due to the large number of calculations, a work in progress is usually only rendered in detail appropriate to the portion of the work being developed at a given time, so in the initial stages of modeling, wireframe and ray casting may be used, even where the target output is ray tracing with radiosity. It is also common to render only parts of the scene at high detail, and to remove objects that are not important to what is currently being developed. Ray casting involves calculating the “view direction” (from camera position), and incrementally following along that “ray cast” through “solid 3d objects” in the scene, while accumulating the resulting value from each point in 3D space. This is related and similar to “ray tracing” except that the raycast is usually not “bounced” off surfaces (where the “ray tracing” indicates that it is tracing out the lights path including bounces).

Words Nearby render

Where an object is intersected, the color value at the point may be evaluated using several methods. In the simplest, the color value of the object at the point of intersection becomes the value of that pixel. A more sophisticated method is to modify the color value by an illumination factor, but without calculating the relationship to a simulated light source. To reduce artifacts, a number of rays in slightly different directions may be averaged. Though the technical details of rendering methods vary, the general challenges to overcome in producing a 2D image on a screen from a 3D representation stored in a scene file are handled by the graphics pipeline in a rendering device such as a GPU. A GPU is a purpose-built device that assists a CPU in performing complex rendering calculations.

This is called rasterization, and is the rendering method used by all current graphics cards. One problem that any rendering system must deal with, no matter which approach it takes, is the sampling problem. Essentially, the rendering process tries to depict a continuous function from image space to colors by using a finite number of pixels. As a consequence of the Nyquist–Shannon sampling theorem (or Kotelnikov theorem), any spatial waveform that can be displayed must consist of at least two pixels, which is proportional to image resolution.

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The reliable leaker, Steve Hemmerstoffer, aka “OnLeaks,” has created renders of the Galaxy Tab S8 Ultra design, and it basically looks like someone cut off the top half of a Macbook Pro, complete with that weird notch. The implementation of a realistic renderer always has some basic element of physical simulation or emulation – some computation which resembles or abstracts render definition a real physical process. Rendering is one of the major sub-topics of 3D computer graphics, and in practice it is always connected to the others. It is the last major step in the graphics pipeline, giving models and animation their final appearance. With the increasing sophistication of computer graphics since the 1970s, it has become a more distinct subject.

The older form of rasterization is characterized by rendering an entire face (primitive) as a single color. Alternatively, rasterization can be done in a more complicated manner by first rendering the vertices of a face and then rendering the pixels of that face as a blending of the vertex colors. This newer method of rasterization utilizes the graphics card’s more taxing shading functions and still achieves better performance because the simpler textures stored in memory use less space. Sometimes designers will use one rasterization method on some faces and the other method on others based on the angle at which that face meets other joined faces, thus increasing speed and not hurting the overall effect.

Ray tracing

In advanced radiosity simulation, recursive, finite-element algorithms ‘bounce’ light back and forth between surfaces in the model, until some recursion limit is reached. The colouring of one surface in this way influences the colouring of a neighbouring surface, and vice versa. The resulting values of illumination throughout the model (sometimes including for empty spaces) are stored and used as additional inputs when performing calculations in a ray-casting or ray-tracing model. Other highly sought features these days may include interactive photorealistic rendering (IPR) and hardware rendering/shading.

Radiosity calculations are viewpoint independent which increases the computations involved, but makes them useful for all viewpoints. If there is little rearrangement of radiosity objects in the scene, the same radiosity data may be reused for a number of frames, making radiosity an effective way to improve on the flatness of ray casting, without seriously impacting the overall rendering time-per-frame. A high-level representation of an image necessarily contains elements in a different domain from pixels. In a schematic drawing, for instance, line segments and curves might be primitives.

Human perception also has limits, and so does not need to be given large-range images to create realism. This can help solve the problem of fitting images into displays, and, furthermore, suggest what short-cuts could be used in the rendering simulation, since certain subtleties will not be noticeable. First, large areas of the image may be empty of primitives; rasterization will ignore these areas, but pixel-by-pixel rendering must pass through them. Second, rasterization can improve cache coherency and reduce redundant work by taking advantage of the fact that the pixels occupied by a single primitive tend to be contiguous in the image. For these reasons, rasterization is usually the approach of choice when interactive rendering is required; however, the pixel-by-pixel approach can often produce higher-quality images and is more versatile because it does not depend on as many assumptions about the image as rasterization. When the pre-image (a wireframe sketch usually) is complete, rendering is used, which adds in bitmap textures or procedural textures, lights, bump mapping and relative position to other objects.