/***************************************************************************
Nintendo 8080 video emulation
***************************************************************************/
#include "emu.h"
#include "includes/n8080.h"
WRITE8_HANDLER( n8080_video_control_w )
{
n8080_state *state = space->machine().driver_data<n8080_state>();
state->m_sheriff_color_mode = (data >> 3) & 3;
state->m_sheriff_color_data = (data >> 0) & 7;
flip_screen_set_no_update(space->machine(), data & 0x20);
}
PALETTE_INIT( n8080 )
{
int i;
for (i = 0; i < 8; i++)
palette_set_color_rgb(machine, i, pal1bit(i >> 0), pal1bit(i >> 1), pal1bit(i >> 2));
}
PALETTE_INIT( helifire )
{
int i;
PALETTE_INIT_CALL(n8080);
for (i = 0; i < 0x100; i++)
{
int level = 0xff * exp(-3 * i / 255.); /* capacitor discharge */
palette_set_color(machine, 0x000 + 8 + i, MAKE_RGB(0x00, 0x00, level)); /* shades of blue */
palette_set_color(machine, 0x100 + 8 + i, MAKE_RGB(0x00, 0xC0, level)); /* shades of blue w/ green star */
palette_set_color(machine, 0x200 + 8 + i, MAKE_RGB(level, 0x00, 0x00)); /* shades of red */
palette_set_color(machine, 0x300 + 8 + i, MAKE_RGB(level, 0xC0, 0x00)); /* shades of red w/ green star */
}
}
void spacefev_start_red_cannon( running_machine &machine )
{
n8080_state *state = machine.driver_data<n8080_state>();
state->m_spacefev_red_cannon = 1;
state->m_cannon_timer->adjust(attotime::from_usec(550 * 68 * 10));
}
static TIMER_CALLBACK( spacefev_stop_red_cannon )
{
n8080_state *state = machine.driver_data<n8080_state>();
state->m_spacefev_red_cannon = 0;
state->m_cannon_timer->adjust(attotime::never);
}
static void helifire_next_line( running_machine &machine )
{
n8080_state *state = machine.driver_data<n8080_state>();
state->m_helifire_mv++;
if (state->m_helifire_sc % 4 == 2)
{
state->m_helifire_mv %= 256;
}
else
{
if (flip_screen_get(machine))
state->m_helifire_mv %= 255;
else
state->m_helifire_mv %= 257;
}
if (state->m_helifire_mv == 128)
{
state->m_helifire_sc++;
}
}
VIDEO_START( spacefev )
{
n8080_state *state = machine.driver_data<n8080_state>();
state->m_cannon_timer = machine.scheduler().timer_alloc(FUNC(spacefev_stop_red_cannon));
flip_screen_set_no_update(machine, 0);
state->save_item(NAME(state->m_spacefev_red_screen));
state->save_item(NAME(state->m_spacefev_red_cannon));
}
VIDEO_START( sheriff )
{
n8080_state *state = machine.driver_data<n8080_state>();
flip_screen_set_no_update(machine, 0);
state->save_item(NAME(state->m_sheriff_color_mode));
state->save_item(NAME(state->m_sheriff_color_data));
}
VIDEO_START( helifire )
{
n8080_state *state = machine.driver_data<n8080_state>();
UINT8 data = 0;
int i;
state->save_item(NAME(state->m_helifire_mv));
state->save_item(NAME(state->m_helifire_sc));
state->save_item(NAME(state->m_helifire_flash));
state->save_item(NAME(state->m_helifire_LSFR));
for (i = 0; i < 63; i++)
{
int bit =
(data >> 6) ^
(data >> 7) ^ 1;
data = (data << 1) | (bit & 1);
state->m_helifire_LSFR[i] = data;
}
flip_screen_set_no_update(machine, 0);
}
SCREEN_UPDATE( spacefev )
{
n8080_state *state = screen->machine().driver_data<n8080_state>();
UINT8 mask = flip_screen_get(screen->machine()) ? 0xff : 0x00;
int x;
int y;
const UINT8* pRAM = state->m_videoram;
const UINT8* pPROM = screen->machine().region("proms")->base();
for (y = 0; y < 256; y++)
{
UINT16* pLine = BITMAP_ADDR16(bitmap, y ^ mask, 0);
for (x = 0; x < 256; x += 8)
{
int n;
UINT8 color = 0;
if (state->m_spacefev_red_screen)
color = 1;
else
{
UINT8 val = pPROM[x >> 3];
if ((x >> 3) == 0x06)
{
color = state->m_spacefev_red_cannon ? 1 : 7;
}
if ((x >> 3) == 0x1b)
{
static const UINT8 ufo_color[] =
{
1, /* red */
2, /* green */
7, /* white */
3, /* yellow */
5, /* magenta */
6, /* cyan */
};
int cycle = screen->frame_number() / 32;
color = ufo_color[cycle % 6];
}
for (n = color + 1; n < 8; n++)
{
if (~val & (1 << n))
{
color = n;
}
}
}
for (n = 0; n < 8; n++)
{
pLine[(x + n) ^ mask] = (pRAM[x >> 3] & (1 << n)) ? color : 0;
}
}
pRAM += 32;
}
return 0;
}
SCREEN_UPDATE( sheriff )
{
n8080_state *state = screen->machine().driver_data<n8080_state>();
UINT8 mask = flip_screen_get(screen->machine()) ? 0xff : 0x00;
const UINT8* pPROM = screen->machine().region("proms")->base();
int x;
int y;
const UINT8* pRAM = state->m_videoram;
for (y = 0; y < 256; y++)
{
UINT16* pLine = BITMAP_ADDR16(bitmap, y ^ mask, 0);
for (x = 0; x < 256; x += 8)
{
int n;
UINT8 color = pPROM[32 * (y >> 3) + (x >> 3)];
if (state->m_sheriff_color_mode == 1 && !(color & 8))
color = state->m_sheriff_color_data ^ 7;
if (state->m_sheriff_color_mode == 2)
color = state->m_sheriff_color_data ^ 7;
if (state->m_sheriff_color_mode == 3)
color = 7;
for (n = 0; n < 8; n++)
{
pLine[(x + n) ^ mask] = ((pRAM[x >> 3] >> n) & 1) ? (color & 7) : 0;
}
}
pRAM += 32;
}
return 0;
}
SCREEN_UPDATE( helifire )
{
n8080_state *state = screen->machine().driver_data<n8080_state>();
int SUN_BRIGHTNESS = input_port_read(screen->machine(), "POT0");
int SEA_BRIGHTNESS = input_port_read(screen->machine(), "POT1");
static const int wave[8] = { 0, 1, 2, 2, 2, 1, 0, 0 };
unsigned saved_mv = state->m_helifire_mv;
unsigned saved_sc = state->m_helifire_sc;
int x;
int y;
for (y = 0; y < 256; y++)
{
UINT16* pLine = BITMAP_ADDR16(bitmap, y, 0);
int level = 120 + wave[state->m_helifire_mv & 7];
/* draw sky */
for (x = level; x < 256; x++)
{
pLine[x] = 0x200 + 8 + SUN_BRIGHTNESS + x - level;
}
/* draw stars */
if (state->m_helifire_mv % 8 == 4) /* upper half */
{
int step = (320 * (state->m_helifire_mv - 0)) % sizeof state->m_helifire_LSFR;
int data =
((state->m_helifire_LSFR[step] & 1) << 6) |
((state->m_helifire_LSFR[step] & 2) << 4) |
((state->m_helifire_LSFR[step] & 4) << 2) |
((state->m_helifire_LSFR[step] & 8) << 0);
pLine[0x80 + data] |= 0x100;
}
if (state->m_helifire_mv % 8 == 5) /* lower half */
{
int step = (320 * (state->m_helifire_mv - 1)) % sizeof state->m_helifire_LSFR;
int data =
((state->m_helifire_LSFR[step] & 1) << 6) |
((state->m_helifire_LSFR[step] & 2) << 4) |
((state->m_helifire_LSFR[step] & 4) << 2) |
((state->m_helifire_LSFR[step] & 8) << 0);
pLine[0x00 + data] |= 0x100;
}
/* draw sea */
for (x = 0; x < level; x++)
{
pLine[x] = 8 + SEA_BRIGHTNESS + x;
}
/* draw foreground */
for (x = 0; x < 256; x += 8)
{
int offset = 32 * y + (x >> 3);
int n;
for (n = 0; n < 8; n++)
{
if (flip_screen_get(screen->machine()))
{
if ((state->m_videoram[offset ^ 0x1fff] << n) & 0x80)
{
pLine[x + n] = state->m_colorram[offset ^ 0x1fff] & 7;
}
}
else
{
if ((state->m_videoram[offset] >> n) & 1)
{
pLine[x + n] = state->m_colorram[offset] & 7;
}
}
}
}
/* next line */
helifire_next_line(screen->machine());
}
state->m_helifire_mv = saved_mv;
state->m_helifire_sc = saved_sc;
return 0;
}
SCREEN_EOF( helifire )
{
n8080_state *state = machine.driver_data<n8080_state>();
int n = (machine.primary_screen->frame_number() >> 1) % sizeof state->m_helifire_LSFR;
int i;
for (i = 0; i < 8; i++)
{
int R = (i & 1);
int G = (i & 2);
int B = (i & 4);
if (state->m_helifire_flash)
{
if (state->m_helifire_LSFR[n] & 0x20)
{
G |= B;
}
if (machine.primary_screen->frame_number() & 0x04)
{
R |= G;
}
}
palette_set_color_rgb(machine,i,
R ? 255 : 0,
G ? 255 : 0,
B ? 255 : 0);
}
for (i = 0; i < 256; i++)
{
helifire_next_line(machine);
}
}