Club Amiga de Montreal - CAM/CAM_CD_1.iso/files/040.lha/Viacom/viacom.c

C/C++ Source or Header | 1987-06-25 | 4.3 KB | 202 lines

/*  :ts=8 bk=0
 *
 * viacom.c:    Another display hack based on common real-life experience
 *        with Viacom cable service.  Viacom is a registered tradmark
 *        of Viacom Cablevision (probably).
 *
 * Leo L. Schwab            8706.4        (415)-456-6565
 *
 * (-:  Some people accuse me of being sick.  :-)
 * (-:   This should convince any doubters.   :-)
 */

#include <exec/types.h>
#include <intuition/intuition.h>
#include <hardware/blit.h>

#define MINTERM        ((int) (NABC | ANBC  |  NABNC | ANBNC))
#define    PLUSX        100
#define PLUSY        50


extern void    *OpenLibrary(), *OpenScreen(), *OpenWindow(), *GetMsg(),
        *AllocRaster(), *CreatePort(), *FindPort();
extern long    VBeamPos();
extern int    rnd();

struct NewWindow windef = {
    0, 15, 200, 10,
    -1, -1,
    CLOSEWINDOW,
    WINDOWCLOSE | WINDOWDEPTH | WINDOWDRAG | ACTIVATE,
    NULL, NULL,
    (UBYTE *) "Patching in...",
    NULL, NULL,
    0, 0, 0, 0,
    WBENCHSCREEN
};

struct Screen    *scr;
struct Window    *win;
struct BitMap    noisemap, phonymap;
struct RastPort    nrp;
struct MsgPort    *flagport;
long        nwide, nhigh;
int        wide, high;
void        *IntuitionBase, *GfxBase;

char        *PORTNAME = "Viacom Public Port";


main ()
{
    register struct Screen *wbs;
    register struct BitMap *wbbm;
    register int i;
    int deep, xoff, yoff;
    int ox[8], oy[8];
    void *msg;

    openstuff ();
    rnd ((short) -VBeamPos());

    /*  Glean important information from system structures  */
    wbs = win -> WScreen;
    wide = wbs -> Width;
    high = wbs -> Height;
    wbbm = wbs -> ViewPort.RasInfo -> BitMap;
    deep = wbbm -> Depth;

    /*  Make the bitplane with the noise in it.  */
    nwide = wide + PLUSX;
    nhigh = high + PLUSY;
    InitBitMap (&noisemap, 1L, nwide, nhigh);
    if (!(noisemap.Planes[0] = AllocRaster (nwide, nhigh)))
        die ("Noise bitmap allocation failed.");

    InitRastPort (&nrp);
    nrp.BitMap = &noisemap;

    mknoise (nwide, nhigh);

    /*  Replace the workbench you see with my phony one.  */
    makephony (wide, high, deep);
    wbs -> ViewPort.RasInfo -> BitMap = &phonymap;
    MakeScreen (wbs);
    RethinkDisplay ();
    SetWindowTitles (win, "\273> Viacom <\253", "Viacom Cablevision");

    while (1) {
        if (msg = GetMsg (win -> UserPort)) {
            ReplyMsg (msg);
            break;
        }

        OwnBlitter ();
        for (i=0; i<deep; i++) {
            while (abs ((xoff = rnd (PLUSX)) - ox[i]) < 10)
                ;
            while (abs ((yoff = rnd (PLUSY)) - oy[i]) < 10)
                ;

            oddblit (wbbm -> Planes[i], phonymap.Planes[i],
                 wide, high,
                 noisemap.Planes[0],
                 (int) nwide, (int) nhigh,
                 xoff, yoff, MINTERM);

            ox[i] = xoff;  oy[i] = yoff;
        }
        DisownBlitter ();
        WaitTOF ();
    }

    /*  Return to normal  */
    wbs -> ViewPort.RasInfo -> BitMap = wbbm;
    MakeScreen (wbs);
    RethinkDisplay ();
    closestuff ();
}

mknoise (wide, high)
long wide, high;
{
    register unsigned int x, i;

    SetRast (&nrp, 0L);
    SetDrMd (&nrp, COMPLEMENT);

    for (x=0; x<wide; x++)
        for (i=0; i<20; i++)
            WritePixel
             (&nrp, (long) x, (long) rnd ((short) high));
}

abs (x)
int x;
{
    return (x < 0 ? -x : x);
}

makephony (wide, high, deep)
int wide, high, deep;
{
    InitBitMap (&phonymap, (long) deep, (long) wide, (long) high);

    while (deep--)    /*  deep decremented after test  */
        if (!(phonymap.Planes[deep] = AllocRaster
                           ((long) wide, (long) high)))
            die ("Couldn't allocate clone bitmap.");
}

openstuff ()
{
    /*
     * Running Viacom multiple times at once could really muck things
     * up, especially if you exit them in the wrong order.  So we do
     * this so that only one Viacom process is active at any given time.
     */
    if (FindPort (PORTNAME))
        die ("You are already connected to Viacom.");
    else
        flagport = CreatePort (PORTNAME, NULL);

    initblitdata ();

    if (!(IntuitionBase = OpenLibrary ("intuition.library", 0L)))
        die ("-=RJ=- is on vacation.");

    if (!(GfxBase = OpenLibrary ("graphics.library", 0L)))
        die ("Dale?  Are you there?");

    if (!(win = OpenWindow (&windef)))
        die ("Window painted shut.");
}

closestuff ()
{
    register int i;

    for (i=0; i<phonymap.Depth; i++)
        if (phonymap.Planes[i])
            FreeRaster
             (phonymap.Planes[i], (long) wide, (long) high);

    if (noisemap.Planes[0])
        FreeRaster (noisemap.Planes[0], nwide, nhigh);

    if (win)        CloseWindow (win);
    if (scr)        CloseScreen (scr);
    if (GfxBase)        CloseLibrary (GfxBase);
    if (IntuitionBase)    CloseLibrary (IntuitionBase);
    if (flagport)        DeletePort (flagport);
}

die (str)
char *str;
{
    puts (str);
    closestuff ();
    exit (20);
}