/***************************************************************************
-= Metal Clash =-
Sprites:
16x16 tiles with 8 pens and 2 color codes,
each sprite can be 1 or 2 tiles tall
Background:
size is 512x256 (scrolling, peculiar memory layout),
16x16 tiles with 8 pens and no color code,
1 byte per tile (tiles are banked)
Foreground:
size is 256x256 (no scrolling),
8x8 tiles with 4 pens and 4 color codes,
2 bytes per tile, low and high per tile priority
***************************************************************************/
#include "emu.h"
#include "includes/metlclsh.h"
WRITE8_HANDLER( metlclsh_rambank_w )
{
metlclsh_state *state = space->machine().driver_data<metlclsh_state>();
if (data & 1)
{
state->m_write_mask = 0;
memory_set_bankptr(space->machine(), "bank1", state->m_bgram);
}
else
{
state->m_write_mask = 1 << (data >> 1);
memory_set_bankptr(space->machine(), "bank1", state->m_otherram);
}
}
WRITE8_HANDLER( metlclsh_gfxbank_w )
{
metlclsh_state *state = space->machine().driver_data<metlclsh_state>();
if (!(data & 4) && (state->m_gfxbank != data))
{
tilemap_mark_all_tiles_dirty(state->m_bg_tilemap);
state->m_gfxbank = data & 3;
}
}
/***************************************************************************
Background tilemap
memory offset of each tile of the tilemap:
00 08 .. 78 100 108 .. 178
. . . . . .
. . . . . .
07 0f .. 7f 107 10f .. 17f
80 88 .. f8 180 188 .. 1f8
. . . . . .
. . . . . .
87 8f .. ff 187 18f .. 1ff
***************************************************************************/
static TILEMAP_MAPPER( metlclsh_bgtilemap_scan )
{
return (row & 7) + ((row & ~7) << 4) + ((col & 0xf) << 3) + ((col & ~0xf) << 4);
}
static TILE_GET_INFO( get_bg_tile_info )
{
metlclsh_state *state = machine.driver_data<metlclsh_state>();
SET_TILE_INFO(1, state->m_bgram[tile_index] + (state->m_gfxbank << 7), 0, 0);
}
WRITE8_HANDLER( metlclsh_bgram_w )
{
metlclsh_state *state = space->machine().driver_data<metlclsh_state>();
/* This ram is banked: it's either the tilemap (e401 = 1)
or bit n of another area (e401 = n << 1)? (that I don't understand) */
if (state->m_write_mask)
{
/* unknown area - the following is almost surely wrong */
// 405b (e401 = e c a 8 6 4 2 0) writes d400++
// 4085 (e401 = e c a 8 6 4 2 0) writes d400++
// 4085 (e401 = e a 6 2) writes d000++
// 405b (e401 = e a 6 2) writes d000++
// state->m_otherram[offset] |= (data & state->m_write_mask);
state->m_otherram[offset] = (state->m_otherram[offset] & ~state->m_write_mask) | (data & state->m_write_mask);
}
else
{
/* tilemap */
state->m_bgram[offset] = data;
tilemap_mark_tile_dirty(state->m_bg_tilemap,offset & 0x1ff);
}
}
/***************************************************************************
Foreground tilemap
Offset: Bits: Value:
0x000 Code
0x400 7--- ---- Priority (0/1 -> over/below sprites and background)
-65- ---- Color
---- --10 Code
***************************************************************************/
static TILE_GET_INFO( get_fg_tile_info )
{
metlclsh_state *state = machine.driver_data<metlclsh_state>();
UINT8 code = state->m_fgram[tile_index + 0x000];
UINT8 attr = state->m_fgram[tile_index + 0x400];
SET_TILE_INFO(2, code + ((attr & 0x03) << 8), (attr >> 5) & 3, 0);
tileinfo->category = ((attr & 0x80) ? 1 : 2);
}
WRITE8_HANDLER( metlclsh_fgram_w )
{
metlclsh_state *state = space->machine().driver_data<metlclsh_state>();
state->m_fgram[offset] = data;
tilemap_mark_tile_dirty(state->m_fg_tilemap, offset & 0x3ff);
}
/***************************************************************************
Video Hardware Init
***************************************************************************/
VIDEO_START( metlclsh )
{
metlclsh_state *state = machine.driver_data<metlclsh_state>();
state->m_otherram = auto_alloc_array(machine, UINT8, 0x800); // banked ram
state->m_bg_tilemap = tilemap_create(machine, get_bg_tile_info, metlclsh_bgtilemap_scan, 16, 16, 32, 16);
state->m_fg_tilemap = tilemap_create(machine, get_fg_tile_info, tilemap_scan_rows, 8, 8, 32, 32);
tilemap_set_transparent_pen(state->m_bg_tilemap, 0);
tilemap_set_transparent_pen(state->m_fg_tilemap, 0);
state->save_pointer(NAME(state->m_otherram), 0x800);
}
/***************************************************************************
Sprites Drawing
Offset: Bits: Value:
0 7--- ---- 0
-65- ---- Code (high bits)
---4 ---- Double height (2 tiles)
---- 3--- Color
---- -2-- Flip X
---- --1- Flip Y
---- ---0 Enable
1 Code (low bits)
2 Y (bottom -> top)
3 X (right -> left)
***************************************************************************/
static void draw_sprites( running_machine &machine, bitmap_t *bitmap, const rectangle *cliprect )
{
metlclsh_state *state = machine.driver_data<metlclsh_state>();
UINT8 *spriteram = state->m_spriteram;
gfx_element *gfx = machine.gfx[0];
int offs;
for (offs = 0; offs < state->m_spriteram_size; offs += 4)
{
int attr, code, color, sx, sy, flipx, flipy, wrapy, sizey;
attr = spriteram[offs];
if (!(attr & 0x01))
continue; // enable
flipy = (attr & 0x02);
flipx = (attr & 0x04);
color = (attr & 0x08) >> 3;
sizey = (attr & 0x10); // double height
code = ((attr & 0x60) << 3) + spriteram[offs + 1];
sx = 240 - spriteram[offs + 3];
if (sx < -7)
sx += 256;
sy = 240 - spriteram[offs + 2];
if (flip_screen_get(machine))
{
sx = 240 - sx; flipx = !flipx;
sy = 240 - sy; flipy = !flipy; if (sizey) sy += 16;
if (sy > 240) sy -= 256;
}
/* Draw twice, at sy and sy + 256 (wrap around) */
for (wrapy = 0; wrapy <= 256; wrapy += 256)
{
if (sizey)
{
drawgfx_transpen(bitmap,cliprect,gfx, code & ~1, color, flipx,flipy,
sx, sy + (flipy ? 0 : -16) + wrapy,0);
drawgfx_transpen(bitmap,cliprect,gfx, code | 1, color, flipx,flipy,
sx,sy + (flipy ? -16 : 0) + wrapy,0);
}
else
{
drawgfx_transpen(bitmap,cliprect,gfx, code, color, flipx,flipy,
sx,sy + wrapy,0);
}
}
}
}
/***************************************************************************
Screen Drawing
Video register e402 (metlclsh seems to only use the values 0,8,9,b):
7654 ---- 0
---- 3--- Background enable
---- -2-- 0
---- --1- Background scroll x high bit
---- ---0 ? (not bg flipx!)
***************************************************************************/
SCREEN_UPDATE( metlclsh )
{
metlclsh_state *state = screen->machine().driver_data<metlclsh_state>();
bitmap_fill(bitmap, cliprect, 0x10);
tilemap_draw(bitmap, cliprect, state->m_fg_tilemap, 1, 0); // low priority tiles of foreground
if (state->m_scrollx[0] & 0x08) // background (if enabled)
{
/* The background seems to be always flipped along x */
tilemap_set_flip(state->m_bg_tilemap, (flip_screen_get(screen->machine()) ? (TILEMAP_FLIPX | TILEMAP_FLIPY) : 0) ^ TILEMAP_FLIPX);
tilemap_set_scrollx(state->m_bg_tilemap, 0, state->m_scrollx[1] + ((state->m_scrollx[0] & 0x02) << 7) );
tilemap_draw(bitmap, cliprect, state->m_bg_tilemap, 0, 0);
}
draw_sprites(screen->machine(), bitmap, cliprect); // sprites
tilemap_draw(bitmap, cliprect, state->m_fg_tilemap, 2, 0); // high priority tiles of foreground
// popmessage("%02X", state->m_scrollx[0]);
return 0;
}