S Y M B O S   D E V E L O P E R   D O C U M E N T A T I O N
Author: Prodatron / SymbiosiS
Date:   27.09.2016
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S C R E E N   M A N A G E R

The screen manager contains all routines for the direct access of the video
hardware.
There is currently only one function, that can be used by applications as well.


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SCREEN MANAGER FUNCTIONS

The screen manager functions have to be called with RST #20 (BNKSCL).
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Address:        #815D (TXTLEN)
Name:           Screen_TextLength
How to call:    rst #20:dw #815d
Input:          HL   = Text address
                A    = Text ram bank (1-15)
                IY   = maximal number of chars (text length)
Output:         DE   = Text width in pixels
                A    = Text height in pixels
Destroyed:      F,BC,HL,IX
Description:    Returns the width and height of a textline in pixels, if it
                would be printed to the screen. You can define the text length
                (number of chars) in IY. If the text is terminated by 0 or 13
                you should use -1 for the maximal text length. Please note,
                that this function always uses the system font for calculating
                the width and height.
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