The calculation process of each of the images of the sequence, rendering, can be performed with various more or less costly techniques calculation time. These techniques will produce images with different degrees of finish and / or realism, calculating shadows, highlights, transparencies, colors, textures …
Rendering is the process of generating an image from a model (or models in what collectively could be called a scene file), by means of computer programs. Also, the results of such a model can be called a rendering. (W)
In general the calculation of an image can range from a few seconds to several hours, depending on the complexity of the elements of the scene and generating technique. If we think a second of animation can require between 25 (PAL) and 30 (NTSC) imagery, we see that the output of any stage may therefore take considerable time just in the phase image generation.
Therefore they often use different levels of refinement of the images, starting with simple models that enable wireline analyze the sequence from the point of view of the frame or movement of objects.
In the figure above is a mixed technique between wireframe representation ( lines or wire) and a model of facets (surfaces) shadows thrown for obtaining and analyzing other aspects such as the incidence of light.
Another aspect to be analyzed in the process is the use of color for each object, and the effects of transparency of translucent materials. In the next picture though these issues are addressed are eliminated shadows thrown.
If we add atmospheric lighting effects and color to the objects we approach the final result.
The textures of objects, as that of the ball rolling down the ramp, and spreading the light produced by the rest of the elements creates glare which must be added the reflections in different elements. Specular forms provide a high degree of credibility to the whole.
The video shown below shows a sequence with three degrees of refinement, summarizing the discussion in this brief introduction.
We must therefore set the work plan for conducting a sequence, way that allows us to refine the finish without assuming a high computational cost.