ELSA GLADIAC 511, Руководство пользователя

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Graphics know-how
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| ELSA GLADIAC 5II |
EN
쑗
The MIP mapping method stores a large number of enlargement
stages for the texture. The depth information of a primitive is then
used to determine which enlargement stages of the texture will be
used in drawing. Information concerning the transparency of the
texture is carried in the alpha channel. Finally, a distinction is made
in MIP mapping between bilinear and trilinear filtering. Bilinear
filtering interpolates between two pixels of two textures, trilinear
filtering interpolates between four pixels for each of two textures.
쑗
Bump mapping introduces a new dimension. Relief or raised textures
can only be generated with the other methods in two dimensions
using light and shadow effects.
The staircase effect is corrected by anti-aliasing. This is either done by
interpolating mixed pixels, in which a new color value is computed from
two adjacent color values.
쎲
The frame buffer
The finished image will not be written to the frame buffer until this
complex sequence of steps is completed. The frame buffer is made up of
front and back buffer. The back buffer acts as a buffer page, in which the
next image to be displayed is built up. The front buffer is the memory
area where the image that appears on the monitor is located. This
prevents the process of image drawing being visible. The duplicate
storage method is also known as double buffering.
Buffer swapping: Display on the monitor
Two possibilities exist for transferring a completed image from the back to
the front buffer, and thus to the display. The obvious method is to copy the
contents to the front buffer one byte at a time, a process known as “blitting”.
Page flipping is significantly faster: in this case the content of the buffer is
not rewritten—the addresses of the front and back buffers are simply
exchanged. As a result, only tiny data volumes are transferred.
The buffer swapping will only ever be performed once the image drawing
process in the back buffer is completed. This procedure should be repeated
at least 20 times a second to give a smooth representation of 3D scenarios.
In this context, we speak of frames per second (fps). This is a very important
value especially for 3D applications. A cinema film runs at 24fps.