Displaying 3D Polygon Animations

Rendering

Rendering is the process of generating an image from a model or models, by means of computer programs. A scene file contains objects in a strictly defined language or data structure; it would contain geometry, viewpoint, texture,lighting, and shading information as a description of 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” may be by analogy with an “artist’s rendering” of a scene. Though the technical details of rendering methods vary, the general challenges to overcome in producing a 2D image from a 3D representation stored in a scene file are outlined as the graphics pipeline along a rendering device, such as a GPU.

3D rendering is initially the process of automatically converting 3D wire frame models into 2D images with 3D photorealistic effects on a computer.

Types of rendering:

Real-time Rendering:

Rendering for interactive media, such as games and simulations, is calculated and displayed in real time, at rates of approximately 20 to 120 frames per second. In real-time rendering, the primary goal is to achieve an as high as possible degree of photorealism at an acceptable minimum rendering speed.

Non Real-time

Animations for non-interactive media, such as feature films and video, are rendered much more slowly. Non-real time rendering enables the leveraging of limited processing power in order to obtain higher image quality. Rendering times for individual frames may vary from a few seconds to several days for complex scenes.

Ray tracing:

This technique is used by creating a path of light through pixels in an image, this is done by using a pane and creating effects. For example if i were to design a short animation of a dog walking under a tree and then through the shade into the sunlight I would have to create a shadow effect to make the sunlight realistic, whilst also keeping the light from hitting the whole of the dogs body. The image below is a perfect example of how ‘Ray Tracing’ works.

Mental ray:

Mental ray is a production-quality rendering application developed by Mental images. It supports ray tracing (a technique for generating an image by tracing the path of light through pixels in an image plane and simulating the effects of its encounters with virtual objects) to generate images. The primary feature of mental ray is the achievement of high performance through parallelism on both multiprocessor machines and across render farms. Mental ray was designed to be integrated into a third-party application using an API or be used as a standalone program using the .mi scene file format for batch-mode rendering. Up to this moment there are many programs integrating this renderer such as Autodesk Maya, 3Ds Max, AutoCAD, Cinema 4D and Revit.

Iray:

 Iray is the world’s first interactive, physically correct rendering solution that generates photorealistic imagery by simulating the physical behavior of light. Iray progressively refines the image until maximum fine detail is reached, providing a single process which smoothly combines interactive pre-visualization and final frame rendering.