/***************************************************************************
Atari Gauntlet hardware
****************************************************************************/
#include "emu.h"
#include "machine/atarigen.h"
#include "video/atarimo.h"
#include "includes/gauntlet.h"
/*************************************
*
* Tilemap callbacks
*
*************************************/
static TILE_GET_INFO( get_alpha_tile_info )
{
gauntlet_state *state = machine.driver_data<gauntlet_state>();
UINT16 data = state->m_alpha[tile_index];
int code = data & 0x3ff;
int color = ((data >> 10) & 0x0f) | ((data >> 9) & 0x20);
int opaque = data & 0x8000;
SET_TILE_INFO(1, code, color, opaque ? TILE_FORCE_LAYER0 : 0);
}
static TILE_GET_INFO( get_playfield_tile_info )
{
gauntlet_state *state = machine.driver_data<gauntlet_state>();
UINT16 data = state->m_playfield[tile_index];
int code = ((state->m_playfield_tile_bank * 0x1000) + (data & 0xfff)) ^ 0x800;
int color = 0x10 + (state->m_playfield_color_bank * 8) + ((data >> 12) & 7);
SET_TILE_INFO(0, code, color, (data >> 15) & 1);
}
/*************************************
*
* Video system start
*
*************************************/
VIDEO_START( gauntlet )
{
static const atarimo_desc modesc =
{
0, /* index to which gfx system */
1, /* number of motion object banks */
1, /* are the entries linked? */
1, /* are the entries split? */
0, /* render in reverse order? */
0, /* render in swapped X/Y order? */
0, /* does the neighbor bit affect the next object? */
8, /* pixels per SLIP entry (0 for no-slip) */
1, /* pixel offset for SLIPs */
0, /* maximum number of links to visit/scanline (0=all) */
0x100, /* base palette entry */
0x100, /* maximum number of colors */
0, /* transparent pen index */
{{ 0,0,0,0x03ff }}, /* mask for the link */
{{ 0 }}, /* mask for the graphics bank */
{{ 0x7fff,0,0,0 }}, /* mask for the code index */
{{ 0 }}, /* mask for the upper code index */
{{ 0,0x000f,0,0 }}, /* mask for the color */
{{ 0,0xff80,0,0 }}, /* mask for the X position */
{{ 0,0,0xff80,0 }}, /* mask for the Y position */
{{ 0,0,0x0038,0 }}, /* mask for the width, in tiles*/
{{ 0,0,0x0007,0 }}, /* mask for the height, in tiles */
{{ 0,0,0x0040,0 }}, /* mask for the horizontal flip */
{{ 0 }}, /* mask for the vertical flip */
{{ 0 }}, /* mask for the priority */
{{ 0 }}, /* mask for the neighbor */
{{ 0 }}, /* mask for absolute coordinates */
{{ 0 }}, /* mask for the special value */
0, /* resulting value to indicate "special" */
0 /* callback routine for special entries */
};
gauntlet_state *state = machine.driver_data<gauntlet_state>();
UINT16 *codelookup;
int i, size;
/* initialize the playfield */
state->m_playfield_tilemap = tilemap_create(machine, get_playfield_tile_info, tilemap_scan_cols, 8,8, 64,64);
/* initialize the motion objects */
atarimo_init(machine, 0, &modesc);
/* initialize the alphanumerics */
state->m_alpha_tilemap = tilemap_create(machine, get_alpha_tile_info, tilemap_scan_rows, 8,8, 64,32);
tilemap_set_transparent_pen(state->m_alpha_tilemap, 0);
/* modify the motion object code lookup table to account for the code XOR */
codelookup = atarimo_get_code_lookup(0, &size);
for (i = 0; i < size; i++)
codelookup[i] ^= 0x800;
/* set up the base color for the playfield */
state->m_playfield_color_bank = state->m_vindctr2_screen_refresh ? 0 : 1;
/* save states */
state->save_item(NAME(state->m_playfield_tile_bank));
state->save_item(NAME(state->m_playfield_color_bank));
}
/*************************************
*
* Horizontal scroll register
*
*************************************/
WRITE16_HANDLER( gauntlet_xscroll_w )
{
gauntlet_state *state = space->machine().driver_data<gauntlet_state>();
UINT16 oldxscroll = *state->m_xscroll;
COMBINE_DATA(state->m_xscroll);
/* if something changed, force a partial update */
if (*state->m_xscroll != oldxscroll)
{
space->machine().primary_screen->update_partial(space->machine().primary_screen->vpos());
/* adjust the scrolls */
tilemap_set_scrollx(state->m_playfield_tilemap, 0, *state->m_xscroll);
atarimo_set_xscroll(0, *state->m_xscroll & 0x1ff);
}
}
/*************************************
*
* Vertical scroll/PF bank register
*
*************************************/
WRITE16_HANDLER( gauntlet_yscroll_w )
{
gauntlet_state *state = space->machine().driver_data<gauntlet_state>();
UINT16 oldyscroll = *state->m_yscroll;
COMBINE_DATA(state->m_yscroll);
/* if something changed, force a partial update */
if (*state->m_yscroll != oldyscroll)
{
space->machine().primary_screen->update_partial(space->machine().primary_screen->vpos());
/* if the bank changed, mark all tiles dirty */
if (state->m_playfield_tile_bank != (*state->m_yscroll & 3))
{
state->m_playfield_tile_bank = *state->m_yscroll & 3;
tilemap_mark_all_tiles_dirty(state->m_playfield_tilemap);
}
/* adjust the scrolls */
tilemap_set_scrolly(state->m_playfield_tilemap, 0, *state->m_yscroll >> 7);
atarimo_set_yscroll(0, (*state->m_yscroll >> 7) & 0x1ff);
}
}
/*************************************
*
* Main refresh
*
*************************************/
SCREEN_UPDATE( gauntlet )
{
gauntlet_state *state = screen->machine().driver_data<gauntlet_state>();
atarimo_rect_list rectlist;
bitmap_t *mobitmap;
int x, y, r;
/* draw the playfield */
tilemap_draw(bitmap, cliprect, state->m_playfield_tilemap, 0, 0);
/* draw and merge the MO */
mobitmap = atarimo_render(0, cliprect, &rectlist);
for (r = 0; r < rectlist.numrects; r++, rectlist.rect++)
for (y = rectlist.rect->min_y; y <= rectlist.rect->max_y; y++)
{
UINT16 *mo = (UINT16 *)mobitmap->base + mobitmap->rowpixels * y;
UINT16 *pf = (UINT16 *)bitmap->base + bitmap->rowpixels * y;
for (x = rectlist.rect->min_x; x <= rectlist.rect->max_x; x++)
if (mo[x])
{
/* verified via schematics:
MO pen 1 clears PF color bit 0x80
*/
if ((mo[x] & 0x0f) == 1)
{
/* Vindicators Part II has extra logic here for the bases */
if (!state->m_vindctr2_screen_refresh || (mo[x] & 0xf0) != 0)
pf[x] ^= 0x80;
}
else
pf[x] = mo[x];
/* erase behind ourselves */
mo[x] = 0;
}
}
/* add the alpha on top */
tilemap_draw(bitmap, cliprect, state->m_alpha_tilemap, 0, 0);
return 0;
}