16 color cga mode 2/2

 BBS: Inland Empire Archive
Date: 04-10-93 (02:18)             Number: 158
From: MATT PRITCHARD @ 930/21      Refer#: NONE
  To: ALL                           Recvd: NO  
Subj: 16 color cga mode     2/2      Conf: (1) 80xxx

>>> Continued from previous message
        b! = dy / dx
    ELSE
        b! = 0
    END IF
    m! = y1 - x1 * b!
    FOR y = y1 TO y2
        IF b! <> 0 THEN
            x = INT((y - m!) / b!) + .5
        ELSE
            x = x1
        END IF
        DrawDot x, y, DrawColor
    NEXT y
END IF

END SUB

SUB ExitMode

    DEF SEG
    SCREEN 0, 0, 0
    WIDTH 80

END SUB


DEFINT A-Z
SUB GetInput

Quit = 0: BackG = 0: CurrentMode = 1

WHILE Quit = 0
DO: a$ = INKEY$: LOOP UNTIL a$ <> ""

SELECT CASE a$
    CASE "=", "+"
        IF BackG < 255 THEN BackG = BackG + 1 ELSE SOUND 1000, .1
        ClearScreen CurrentMode, BackG, 1
    CASE "-"
        IF BackG > 0 THEN BackG = BackG - 1 ELSE SOUND 1000, .1
        ClearScreen CurrentMode, BackG, 1
    CASE "L", "l"
        x1 = INT(79 * RND)
        y1 = INT(99 * RND)
        x2 = INT(79 * RND)
        y2 = INT(99 * RND)
        DrawColor = (255 * RND)
        DrawLine x1, y1, x2, y2, DrawColor
    CASE "M", "m"
        IF CurrentMode <> 0 THEN CurrentMode = 0 ELSE CurrentMode = 1
        ClearScreen CurrentMode, 0, 0
    CASE "Q", "q"
        Quit = 1
END SELECT

a$ = ""     'clear a$ variable for more input

WEND
END SUB

SUB Pause
    WHILE INKEY$ = "": WEND
END SUB

SUB ScreenMode160 (Mode%)

 WIDTH 80                             ' 80 COLUMN MODE
 SCREEN 0, 1, 0, 0                    ' COLOR MODE
 OUT &H3D8, 9                         ' DISABLES BLINK BIT
 DEF SEG = &HB800                     ' COLOR DISPLAY AREA
 FOR I = 0 TO 80 * 100 * 2 STEP 2     ' FILL "SCREEN"
    POKE I, 222                       ' HALF AND HALF CHAR
    POKE I + 1, 0                     ' BLACK ON BLACK
 NEXT I
 OUT &H3D4, 4                         ' R4  SELECTED
 OUT &H3D5, 124                       ' R4  VERTICAL TOTAL
 OUT &H3D4, 6                         ' R6  SELECTED
 OUT &H3D5, 100                       ' R6  VERTICAL DISPLAYED
 OUT &H3D4, 7                         ' R7  SELECTED
 OUT &H3D5, 112                       ' R7  VERTICAL SYNC
 OUT &H3D4, 9                         ' R9  SELECTED
 OUT &H3D5, 1                         ' R9  SCAN LINES (2)

 IF Mode% <> 0 THEN ClearScreen 1, 0, 0

END SUB


SUB ClearScreen (Mode%, DrawColor%, NoClear%)

'check for out of bounds

IF DrawColor < 0 OR DrawColor > 255 THEN SOUND 1000, .1: EXIT SUB

'check for box or fuzz mode

IF Mode% <> 0 THEN

 'clear screen:      &HB1 = 177, DrawColor = 'Background Color'

 FOR CHAR = 0 TO 15998 STEP 2: POKE CHAR, &HB1: NEXT

 IF NoClear% <> 0 THEN

    FOR ATTR = 1 TO 16000 STEP 2: POKE ATTR, DrawColor: NEXT

 END IF

ELSE

 'black screen:

 FOR I = 0 TO 80 * 100 * 2 STEP 2     ' fill the "screen"
    POKE I, &HDE                      ' decimal for &HDE=222

 IF NoClear% <> 0 THEN

    POKE I + 1, DrawColor             ' color black on black

 END IF

 NEXT I

END IF

END SUB

------------------------
That's it
-Matt Pritchard
===
 * SLMR 2.1a * Yesterday I got so old

--- InterPCB 1.50
 # Origin: CENTRAL BBS -Texas' BEST BBS! 214-393-7090 HST  3+GIGs (8:930/21)
 * Origin: Gateway System to/from RBBS-NET (RBBS-PC 1:10/8)