source: buchla-68k/ram/itcpos.c@ e15f784

/*
   =============================================================================
        itcpos.c -- text cursor positioning for the instrument display
        Version 12 -- 1989-12-19 -- D.N. Lynx Crowe
   =============================================================================
*/

#include "ram.h"

#define CW_0    0x0000
#define CW_F    0xFFFF

static uint16_t itcur[] = {

        CW_0, CW_0, CW_0, CW_0, /* 0 */
        CW_0, CW_0, CW_0, CW_0, /* 1 */
        CW_0, CW_0, CW_0, CW_0, /* 2 */
        CW_0, CW_0, CW_0, CW_0, /* 3 */
        CW_0, CW_0, CW_0, CW_0, /* 4 */
        CW_0, CW_0, CW_0, CW_0, /* 5 */
        CW_0, CW_0, CW_0, CW_0, /* 6 */
        CW_0, CW_0, CW_0, CW_0, /* 7 */
        CW_0, CW_0, CW_0, CW_0, /* 8 */
        CW_0, CW_0, CW_0, CW_0, /* 9 */
        CW_0, CW_0, CW_0, CW_0, /* 10 */
        CW_0, CW_0, CW_0, CW_0, /* 11 */
        CW_F, CW_F, CW_0, CW_0, /* 12 */
        CW_0, CW_0, CW_0, CW_0, /* 13 */
        CW_0, CW_0, CW_0, CW_0, /* 14 */
        CW_0, CW_0, CW_0, CW_0  /* 15 */
};

/*
   =============================================================================
        itcini() -- initialize instrument text cursor
   =============================================================================
*/

void itcini(int16_t color)
{
        if ((v_regs[5] & 0x0180) NE 0x0100)
                vbank(1);

        andcopy(v_cur, itcur, exp_c(color), 64);
}

/*
   =============================================================================
        itcpos() -- position the instrument text cursor at ('row', 'col')
   =============================================================================
*/

void itcpos(int16_t row, int16_t col)
{
        register int16_t yrow, xcol;
        register struct octent *op;

        if (v_regs[5] & 0x0180)         /* point at the control bank */
                vbank(0);

        yrow = row * 14;                /* get cursor display position */
        xcol = col * 8;

        op = &v_obtab[TCURS];           /* point at v_obtab entry */
        setipl(VID_DI);                 /* disable Vertical Interval interrupt */
        v_odtab[TCPRI][0] &= ~V_BLA;    /* blank the object */
        objclr(TCPRI);                  /* turn off the old location */

        op->objx = xcol;                /* update v_obtab entry */
        op->objy = yrow;
        op->obase = &v_cur[0];
        op->odtw1 = (uint16_t)(0x0400 | (0x03FF & (xcol >> 1)));

        SetPri(TCURS, TCPRI);           /* turn on the new location */

        stcrow = row;                   /* update cursor position */
        stccol = col;
}

/*
   =============================================================================
        advicur() -- advance the instrument display text cursor
   =============================================================================
*/

void advicur(void)
{
        register int16_t newcol;

        if (infield(stcrow, stccol, curfet))
                cfetp = infetp;
        else
                return;

        newcol = stccol + 1;

        if (newcol LE cfetp->frcol)
                itcpos(stcrow, newcol);
}

/*
   =============================================================================
        bspicur() -- backspace the instrument display text cursor
   =============================================================================
*/

void bspicur(void)
{
        register int16_t newcol;

        if (infield(stcrow, stccol, curfet))
                cfetp = infetp;
        else
                return;

        newcol = stccol - 1;

        if (newcol GE cfetp->flcol)
                itcpos(stcrow, newcol);
}