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•Multiple light sources,

•Splines as primitives,

•Estimates of non-point light sources,

•New primitives,

12.9 RADIOSITY

• An emerging technique for rendering ---XXXXXXXXXX

12.10 ADVANCED GRAPHICS TECHNIQUES

12.10.1 Animation

•To simulate motion we collect a set of still frames of a rendered object being translated and rotated. These are played back to simulate the motion.

•The paths of motion may be defined using splines, equations, functions, etc.

•Some tricks used for doing animation are,

-Only drawing the part of the screen that is changing

-Blurring images for fast moving objects reduced the flicker.

-Alternating two pictures (double buffering). While one picture is being drawn, the previous picture is displayed.

•Buffer swapping gives smooth looking graphics by:

i)Swapping the screen with a memory block,

ii)Erasing the previous image (within a bounding box),

iii)Redrawing the image,

iv)Repeat the loop.

•When using interactive animations a program structure is required that separated user inputs from rendering.