Tseng Qtec VGA 1024, Руководство по установке

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A programmer might use this function when multiple zoom
windows may be used in an application, but the last zoom
window must be preserved. The programmer can query the
current zoom window, change window, and then restore the zoom
window to the original settings.
Lattice C Example
#include<dos.h>
<3— zoom__win d o w (window)
int win d o w [];
{
union REGS in,out;
in.x.ax = 5;
in.x.bx = getdatas();/* Data segment of window[] */
in.x.cx = (int)window;
int86(zoom__int,&in,&out);
>
Set Z
qqir
Window
Function Code
AX = 6
Arguments
BX = Segment address of window coordinate array
CX = Offset address of window coordinate array
Description
This function will set the zoom window. The zoom window is
the area of the display where zooming begins. The programmer
must pass the segment and offset values of an array which
contains the coordinates of the new zoom window. The format
of the array should be as follows:
offset [0] x start of zoom window
offset [1] y start of zoom window
offset [2] x end of zoom window
offset [3] y end of zoom window
Note the restrictions on x coordinate values described in the
equation below.
0 <= (x__zoom__ end - x__zoom__ start/
(x__zoom__ factor + 1) % (x__zoom__factor + 1)
In English this means that the width of the zoom window must
be a multiple of the pixel replication factor.
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