/***********************************************
+-------------------------------------+
| |
| CAL OMEGA - SYSTEMS 903/904/905/906 |
| |
| Driver by Roberto Fresca. |
| |
+-------------------------------------+
* Video Hardware *
************************************************/
#include "emu.h"
#include "includes/calomega.h"
WRITE8_HANDLER( calomega_videoram_w )
{
calomega_state *state = space->machine().driver_data<calomega_state>();
state->m_videoram[offset] = data;
tilemap_mark_tile_dirty(state->m_bg_tilemap, offset);
}
WRITE8_HANDLER( calomega_colorram_w )
{
calomega_state *state = space->machine().driver_data<calomega_state>();
state->m_colorram[offset] = data;
tilemap_mark_tile_dirty(state->m_bg_tilemap, offset);
}
static TILE_GET_INFO( get_bg_tile_info )
{
calomega_state *state = machine.driver_data<calomega_state>();
/* - bits -
7654 3210
--xx xx-- tiles color.
---- --x- tiles bank.
xx-- ---x seems unused. */
int attr = state->m_colorram[tile_index];
int code = state->m_videoram[tile_index];
int bank = (attr & 0x02) >> 1; /* bit 1 switch the gfx banks */
int color = (attr & 0x3c); /* bits 2-3-4-5 for color */
if (attr == 0x3a) /* Is the palette wrong? */
color = 0x3b; /* 0x3b is the best match */
if (attr == 0x36) /* Is the palette wrong? */
color = 0x3a; /* 0x3a is the best match */
if (attr == 0x32) /* Is the palette wrong? */
color = 0x39; /* 0x39 is the best match */
SET_TILE_INFO(bank, code, color, 0);
}
VIDEO_START( calomega )
{
calomega_state *state = machine.driver_data<calomega_state>();
state->m_bg_tilemap = tilemap_create(machine, get_bg_tile_info, tilemap_scan_rows, 8, 8, 32, 31);
}
SCREEN_UPDATE( calomega )
{
calomega_state *state = screen->machine().driver_data<calomega_state>();
tilemap_draw(bitmap, cliprect, state->m_bg_tilemap, 0, 0);
return 0;
}
PALETTE_INIT( calomega )
{
/* prom bits
7654 3210
---- ---x red component.
---- --x- green component.
---- -x-- blue component.
xxxx x--- unused.
*/
int i;
/* 00000BGR */
if (color_prom == 0) return;
for (i = 0;i < machine.total_colors();i++)
{
int bit0, bit1, bit2, r, g, b;
/* red component */
bit0 = (color_prom[i] >> 0) & 0x01;
r = bit0 * 0xff;
/* green component */
bit1 = (color_prom[i] >> 1) & 0x01;
g = bit1 * 0xff;
/* blue component */
bit2 = (color_prom[i] >> 2) & 0x01;
b = bit2 * 0xff;
palette_set_color(machine, i, MAKE_RGB(r, g, b));
}
}