Files
86Box/src/video/vid_ega_render.c

489 lines
13 KiB
C

/*
* 86Box A hypervisor and IBM PC system emulator that specializes in
* running old operating systems and software designed for IBM
* PC systems and compatibles from 1981 through fairly recent
* system designs based on the PCI bus.
*
* This file is part of the 86Box distribution.
*
* EGA renderers.
*
*
*
* Author: Sarah Walker, <http://pcem-emulator.co.uk/>
* Miran Grca, <mgrca8@gmail.com>
*
* Copyright 2008-2019 Sarah Walker.
* Copyright 2016-2019 Miran Grca.
*/
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <wchar.h>
#include <86box/86box.h>
#include <86box/device.h>
#include <86box/timer.h>
#include <86box/mem.h>
#include <86box/rom.h>
#include <86box/video.h>
#include <86box/vid_ega.h>
int
ega_display_line(ega_t *ega)
{
int y_add = (enable_overscan) ? (overscan_y >> 1) : 0;
unsigned int dl = ega->displine;
if (ega->crtc[9] & 0x1f)
dl -= (ega->crtc[8] & 0x1f);
dl += y_add;
dl &= 0x7ff;
return dl;
}
void
ega_render_blank(ega_t *ega)
{
int x, xx;
if ((ega->displine + ega->y_add) < 0)
return;
for (x = 0; x < (ega->hdisp + ega->scrollcache); x++) {
switch (ega->seqregs[1] & 9) {
case 0:
for (xx = 0; xx < 9; xx++) buffer32->line[ega->displine + ega->y_add][ega->x_add + (x * 9) + xx] = 0;
break;
case 1:
for (xx = 0; xx < 8; xx++) buffer32->line[ega->displine + ega->y_add][ega->x_add + (x * 8) + xx] = 0;
break;
case 8:
for (xx = 0; xx < 18; xx++) buffer32->line[ega->displine + ega->y_add][ega->x_add + (x * 18) + xx] = 0;
break;
case 9:
for (xx = 0; xx < 16; xx++) buffer32->line[ega->displine + ega->y_add][ega->x_add + (x * 16) + xx] = 0;
break;
}
}
}
void
ega_render_overscan_left(ega_t *ega)
{
int i;
if ((ega->displine + ega->y_add) < 0)
return;
if (ega->scrblank || (ega->hdisp == 0))
return;
for (i = 0; i < ega->x_add; i++)
buffer32->line[ega->displine + ega->y_add][i] = ega->overscan_color;
}
void
ega_render_overscan_right(ega_t *ega)
{
int i, right;
if ((ega->displine + ega->y_add) < 0)
return;
if (ega->scrblank || (ega->hdisp == 0))
return;
right = (overscan_x >> 1) + ega->scrollcache;
for (i = 0; i < right; i++)
buffer32->line[ega->displine + ega->y_add][ega->x_add + ega->hdisp + i] = ega->overscan_color;
}
void
ega_render_text_40(ega_t *ega)
{
uint32_t *p;
int x, xx;
int drawcursor, xinc;
uint8_t chr, attr, dat;
uint32_t charaddr;
int fg, bg;
if ((ega->displine + ega->y_add) < 0)
return;
if (ega->firstline_draw == 2000)
ega->firstline_draw = ega->displine;
ega->lastline_draw = ega->displine;
if (fullchange) {
p = &buffer32->line[ega->displine + ega->y_add][ega->x_add];
xinc = (ega->seqregs[1] & 1) ? 16 : 18;
for (x = 0; x < (ega->hdisp + ega->scrollcache); x += xinc) {
drawcursor = ((ega->ma == ega->ca) && ega->con && ega->cursoron);
chr = ega->vram[(ega->ma << 1) & ega->vrammask];
attr = ega->vram[((ega->ma << 1) + 1) & ega->vrammask];
if (attr & 8) charaddr = ega->charsetb + (chr * 128);
else charaddr = ega->charseta + (chr * 128);
if (drawcursor) {
bg = ega->pallook[ega->egapal[attr & 15]];
fg = ega->pallook[ega->egapal[attr >> 4]];
} else {
fg = ega->pallook[ega->egapal[attr & 15]];
bg = ega->pallook[ega->egapal[attr >> 4]];
if (attr & 0x80 && ega->attrregs[0x10] & 8) {
bg = ega->pallook[ega->egapal[(attr >> 4) & 7]];
if (ega->blink & 16)
fg = bg;
}
}
dat = ega->vram[charaddr + (ega->sc << 2)];
if (ega->seqregs[1] & 1) {
for (xx = 0; xx < 16; xx += 2)
p[xx] = p[xx + 1] = (dat & (0x80 >> (xx >> 1))) ? fg : bg;
} else {
for (xx = 0; xx < 16; xx += 2)
p[xx] = p[xx + 1] = (dat & (0x80 >> (xx >> 1))) ? fg : bg;
if ((chr & ~0x1f) != 0xc0 || !(ega->attrregs[0x10] & 4))
p[16] = p[17] = bg;
else
p[16] = p[17] = (dat & 1) ? fg : bg;
}
ega->ma += 4;
p += xinc;
}
ega->ma &= ega->vrammask;
}
}
void
ega_render_text_80(ega_t *ega)
{
uint32_t *p;
int x, xx;
int drawcursor, xinc;
uint8_t chr, attr, dat;
uint32_t charaddr;
int fg, bg;
if ((ega->displine + ega->y_add) < 0)
return;
if (ega->firstline_draw == 2000)
ega->firstline_draw = ega->displine;
ega->lastline_draw = ega->displine;
if (fullchange) {
p = &buffer32->line[ega->displine + ega->y_add][ega->x_add];
xinc = (ega->seqregs[1] & 1) ? 8 : 9;
for (x = 0; x < (ega->hdisp + ega->scrollcache); x += xinc) {
drawcursor = ((ega->ma == ega->ca) && ega->con && ega->cursoron);
chr = ega->vram[(ega->ma << 1) & ega->vrammask];
attr = ega->vram[((ega->ma << 1) + 1) & ega->vrammask];
if (attr & 8) charaddr = ega->charsetb + (chr * 128);
else charaddr = ega->charseta + (chr * 128);
if (drawcursor) {
bg = ega->pallook[ega->egapal[attr & 15]];
fg = ega->pallook[ega->egapal[attr >> 4]];
} else {
fg = ega->pallook[ega->egapal[attr & 15]];
bg = ega->pallook[ega->egapal[attr >> 4]];
if (attr & 0x80 && ega->attrregs[0x10] & 8) {
bg = ega->pallook[ega->egapal[(attr >> 4) & 7]];
if (ega->blink & 16)
fg = bg;
}
}
dat = ega->vram[charaddr + (ega->sc << 2)];
if (ega->seqregs[1] & 1) {
for (xx = 0; xx < 8; xx++)
p[xx] = (dat & (0x80 >> xx)) ? fg : bg;
} else {
for (xx = 0; xx < 8; xx++)
p[xx] = (dat & (0x80 >> xx)) ? fg : bg;
if ((chr & ~0x1F) != 0xC0 || !(ega->attrregs[0x10] & 4))
p[8] = bg;
else
p[8] = (dat & 1) ? fg : bg;
}
ega->ma += 4;
p += xinc;
}
ega->ma &= ega->vrammask;
}
}
void
ega_render_2bpp_lowres(ega_t *ega)
{
int x;
uint8_t dat[2];
uint32_t addr, *p;
if ((ega->displine + ega->y_add) < 0)
return;
p = &buffer32->line[ega->displine + ega->y_add][ega->x_add];
if (ega->firstline_draw == 2000)
ega->firstline_draw = ega->displine;
ega->lastline_draw = ega->displine;
for (x = 0; x <= (ega->hdisp + ega->scrollcache); x += 16) {
addr = ega->ma;
if (!(ega->crtc[0x17] & 0x40)) {
addr = (addr << 1) & ega->vrammask;
addr &= ~7;
if ((ega->crtc[0x17] & 0x20) && (ega->ma & 0x20000))
addr |= 4;
if (!(ega->crtc[0x17] & 0x20) && (ega->ma & 0x8000))
addr |= 4;
}
if (!(ega->crtc[0x17] & 0x01))
addr = (addr & ~0x8000) | ((ega->sc & 1) ? 0x8000 : 0);
if (!(ega->crtc[0x17] & 0x02))
addr = (addr & ~0x10000) | ((ega->sc & 2) ? 0x10000 : 0);
dat[0] = ega->vram[addr];
dat[1] = ega->vram[addr | 0x1];
if (ega->seqregs[1] & 4)
ega->ma += 2;
else
ega->ma += 4;
ega->ma &= ega->vrammask;
p[0] = p[1] = ega->pallook[ega->egapal[(dat[0] >> 6) & 3]];
p[2] = p[3] = ega->pallook[ega->egapal[(dat[0] >> 4) & 3]];
p[4] = p[5] = ega->pallook[ega->egapal[(dat[0] >> 2) & 3]];
p[6] = p[7] = ega->pallook[ega->egapal[dat[0] & 3]];
p[8] = p[9] = ega->pallook[ega->egapal[(dat[1] >> 6) & 3]];
p[10] = p[11] = ega->pallook[ega->egapal[(dat[1] >> 4) & 3]];
p[12] = p[13] = ega->pallook[ega->egapal[(dat[1] >> 2) & 3]];
p[14] = p[15] = ega->pallook[ega->egapal[dat[1] & 3]];
p += 16;
}
}
void
ega_render_2bpp_highres(ega_t *ega)
{
int x;
uint8_t dat[2];
uint32_t addr, *p;
if ((ega->displine + ega->y_add) < 0)
return;
p = &buffer32->line[ega->displine + ega->y_add][ega->x_add];
if (ega->firstline_draw == 2000)
ega->firstline_draw = ega->displine;
ega->lastline_draw = ega->displine;
for (x = 0; x <= (ega->hdisp + ega->scrollcache); x += 8) {
addr = ega->ma;
if (!(ega->crtc[0x17] & 0x40)) {
addr = (addr << 1) & ega->vrammask;
addr &= ~7;
if ((ega->crtc[0x17] & 0x20) && (ega->ma & 0x20000))
addr |= 4;
if (!(ega->crtc[0x17] & 0x20) && (ega->ma & 0x8000))
addr |= 4;
}
if (!(ega->crtc[0x17] & 0x01))
addr = (addr & ~0x8000) | ((ega->sc & 1) ? 0x8000 : 0);
if (!(ega->crtc[0x17] & 0x02))
addr = (addr & ~0x10000) | ((ega->sc & 2) ? 0x10000 : 0);
dat[0] = ega->vram[addr];
dat[1] = ega->vram[addr | 0x1];
if (ega->seqregs[1] & 4)
ega->ma += 2;
else
ega->ma += 4;
ega->ma &= ega->vrammask;
p[0] = ega->pallook[ega->egapal[(dat[0] >> 6) & 3]];
p[1] = ega->pallook[ega->egapal[(dat[0] >> 4) & 3]];
p[2] = ega->pallook[ega->egapal[(dat[0] >> 2) & 3]];
p[3] = ega->pallook[ega->egapal[dat[0] & 3]];
p[4] = ega->pallook[ega->egapal[(dat[1] >> 6) & 3]];
p[5] = ega->pallook[ega->egapal[(dat[1] >> 4) & 3]];
p[6] = ega->pallook[ega->egapal[(dat[1] >> 2) & 3]];
p[7] = ega->pallook[ega->egapal[dat[1] & 3]];
p += 8;
}
}
void
ega_render_4bpp_lowres(ega_t *ega)
{
int x, oddeven;
uint8_t dat, edat[4];
uint32_t addr, *p;
if ((ega->displine + ega->y_add) < 0)
return;
p = &buffer32->line[ega->displine + ega->y_add][ega->x_add];
if (ega->firstline_draw == 2000)
ega->firstline_draw = ega->displine;
ega->lastline_draw = ega->displine;
for (x = 0; x <= (ega->hdisp + ega->scrollcache); x += 16) {
addr = ega->ma;
oddeven = 0;
if (!(ega->crtc[0x17] & 0x40)) {
addr = (addr << 1) & ega->vrammask;
if (ega->seqregs[1] & 4)
oddeven = (addr & 4) ? 1 : 0;
addr &= ~7;
if ((ega->crtc[0x17] & 0x20) && (ega->ma & 0x20000))
addr |= 4;
if (!(ega->crtc[0x17] & 0x20) && (ega->ma & 0x8000))
addr |= 4;
}
if (!(ega->crtc[0x17] & 0x01))
addr = (addr & ~0x8000) | ((ega->sc & 1) ? 0x8000 : 0);
if (!(ega->crtc[0x17] & 0x02))
addr = (addr & ~0x10000) | ((ega->sc & 2) ? 0x10000 : 0);
if (ega->seqregs[1] & 4) {
edat[0] = ega->vram[addr | oddeven];
edat[2] = ega->vram[addr | oddeven | 0x2];
edat[1] = edat[3] = 0;
ega->ma += 2;
} else {
edat[0] = ega->vram[addr];
edat[1] = ega->vram[addr | 0x1];
edat[2] = ega->vram[addr | 0x2];
edat[3] = ega->vram[addr | 0x3];
ega->ma += 4;
}
ega->ma &= ega->vrammask;
dat = edatlookup[edat[0] >> 6][edat[1] >> 6] | (edatlookup[edat[2] >> 6][edat[3] >> 6] << 2);
p[0] = p[1] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[2] = p[3] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
dat = edatlookup[(edat[0] >> 4) & 3][(edat[1] >> 4) & 3] | (edatlookup[(edat[2] >> 4) & 3][(edat[3] >> 4) & 3] << 2);
p[4] = p[5] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[6] = p[7] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
dat = edatlookup[(edat[0] >> 2) & 3][(edat[1] >> 2) & 3] | (edatlookup[(edat[2] >> 2) & 3][(edat[3] >> 2) & 3] << 2);
p[8] = p[9] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[10] = p[11] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
dat = edatlookup[edat[0] & 3][edat[1] & 3] | (edatlookup[edat[2] & 3][edat[3] & 3] << 2);
p[12] = p[13] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[14] = p[15] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
p += 16;
}
}
void
ega_render_4bpp_highres(ega_t *ega)
{
int x, oddeven;
uint8_t dat, edat[4];
uint32_t addr, *p;
if ((ega->displine + ega->y_add) < 0)
return;
p = &buffer32->line[ega->displine + ega->y_add][ega->x_add];
if (ega->firstline_draw == 2000)
ega->firstline_draw = ega->displine;
ega->lastline_draw = ega->displine;
for (x = 0; x <= (ega->hdisp + ega->scrollcache); x += 8) {
addr = ega->ma;
oddeven = 0;
if (!(ega->crtc[0x17] & 0x40)) {
addr = (addr << 1) & ega->vrammask;
if (ega->seqregs[1] & 4)
oddeven = (addr & 4) ? 1 : 0;
addr &= ~7;
if ((ega->crtc[0x17] & 0x20) && (ega->ma & 0x20000))
addr |= 4;
if (!(ega->crtc[0x17] & 0x20) && (ega->ma & 0x8000))
addr |= 4;
}
if (!(ega->crtc[0x17] & 0x01))
addr = (addr & ~0x8000) | ((ega->sc & 1) ? 0x8000 : 0);
if (!(ega->crtc[0x17] & 0x02))
addr = (addr & ~0x10000) | ((ega->sc & 2) ? 0x10000 : 0);
if (ega->seqregs[1] & 4) {
edat[0] = ega->vram[addr | oddeven];
edat[2] = ega->vram[addr | oddeven | 0x2];
edat[1] = edat[3] = 0;
ega->ma += 2;
} else {
*(uint32_t *)(&edat[0]) = *(uint32_t *)(&ega->vram[addr]);
ega->ma += 4;
}
ega->ma &= ega->vrammask;
dat = edatlookup[edat[0] >> 6][edat[1] >> 6] | (edatlookup[edat[2] >> 6][edat[3] >> 6] << 2);
p[0] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[1] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
dat = edatlookup[(edat[0] >> 4) & 3][(edat[1] >> 4) & 3] | (edatlookup[(edat[2] >> 4) & 3][(edat[3] >> 4) & 3] << 2);
p[2] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[3] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
dat = edatlookup[(edat[0] >> 2) & 3][(edat[1] >> 2) & 3] | (edatlookup[(edat[2] >> 2) & 3][(edat[3] >> 2) & 3] << 2);
p[4] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[5] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
dat = edatlookup[edat[0] & 3][edat[1] & 3] | (edatlookup[edat[2] & 3][edat[3] & 3] << 2);
p[6] = ega->pallook[ega->egapal[(dat >> 4) & ega->plane_mask]];
p[7] = ega->pallook[ega->egapal[dat & ega->plane_mask]];
p += 8;
}
}