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@@ -146,11 +146,11 @@ errVioNoSuchMode = errVioBase + 3; { No such video mode }
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The following constants can be read to get some information about the
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current screen:
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\begin{verbatim}
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-ScreenWidth : Word = 0;
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-ScreenHeight : Word = 0;
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+ScreenWidth : Word = 0; { Width of the screen, in characters }
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+ScreenHeight : Word = 0; { Height of the screen, in characters }
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LowAscii : Boolean = true;
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NoExtendedFrame : Boolean = false;
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-FVMaxWidth = 132;
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+FVMaxWidth = 132;
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\end{verbatim}
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The error-handling code uses the following constants:
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\begin{verbatim}
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@@ -174,9 +174,12 @@ supports colors, or \var{False} if not.
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Color : Boolean;
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end;
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\end{verbatim}
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-\var{TVideoCell} describes one character on the screen. The high byte
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+\var{TVideoCell} describes one character on the screen. One of the bytes
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contains the color attribute with which the character is drawn on the screen,
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-and the low byte contains the ASCII code of the character to be drawn.
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+and the other byte contains the ASCII code of the character to be drawn. The
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+exact position of the different bytes in the record is operating system specific.
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+On most little-endian systems, the high byte represents the color attribute,
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+while the low-byte represents the ASCII code of the character to be drawn.
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\begin{verbatim}
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TVideoCell = Word;
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PVideoCell = ^TVideoCell;
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@@ -234,12 +237,10 @@ CursorX, CursorY : Word;
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\var{ScreenColor} indicates whether the current screen supports colors.
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\var{CursorX,CursorY} contain the current cursor position.
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-The following variables form the heart of the \file{Video} unit: The
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+The following variable forms the heart of the \file{Video} unit: The
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\var{VideoBuf} array represents the physical screen. Writing to this
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array and calling \seep{UpdateScreen} will write the actual characters
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-to the screen. \var{VideoBufSize} contains the actual screen size, and is
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-equal to the product of the number of columns times the number of lines
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-on the screen (\var{ScreenWidth*ScreenHeight}).
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+to the screen.
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\begin{verbatim}
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VideoBuf : PVideoBuf;
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OldVideoBuf : PVideoBuf;
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carl