#include "driver.h"
static tilemap *bg_tilemap, *fg_tilemap;
UINT8* mermaid_videoram2;
UINT8* mermaid_bg_scrollram;
UINT8* mermaid_fg_scrollram;
static int rougien_gfxbank1, rougien_gfxbank2;
static rectangle spritevisiblearea =
{
0*8, 26*8-1,
2*8, 30*8-1
};
static rectangle flip_spritevisiblearea =
{
6*8, 31*8-1,
2*8, 30*8-1
};
PALETTE_INIT( mermaid )
{
#define TOTAL_COLORS(gfxn) (machine->gfx[gfxn]->total_colors * machine->gfx[gfxn]->color_granularity)
#define COLOR(gfxn,offs) (colortable[machine->drv->gfxdecodeinfo[gfxn].color_codes_start + offs])
// first, the char actor/sprite palette
int i;
for (i = 0; i < TOTAL_COLORS(0); i++)
{
int r = 0x21 * BIT(*color_prom, 0) + 0x47 * BIT(*color_prom, 1) + 0x97 * BIT(*color_prom, 2);
int g = 0x21 * BIT(*color_prom, 3) + 0x47 * BIT(*color_prom, 4) + 0x97 * BIT(*color_prom, 5);
int b = 0x47 * BIT(*color_prom, 6) + 0x97 * BIT(*color_prom, 7);
palette_set_color(machine, i, MAKE_RGB(r, g, b));
color_prom++;
}
// blue background
palette_set_color(machine, TOTAL_COLORS(0), MAKE_RGB(0, 0, 0xff));
// set up background palette
COLOR(2,0) = 32;
COLOR(2,1) = 33;
COLOR(2,2) = 64;
COLOR(2,3) = 33;
}
WRITE8_HANDLER( mermaid_videoram2_w )
{
mermaid_videoram2[offset] = data;
tilemap_mark_tile_dirty(bg_tilemap, offset);
}
WRITE8_HANDLER( mermaid_videoram_w )
{
videoram[offset] = data;
tilemap_mark_tile_dirty(fg_tilemap, offset);
}
WRITE8_HANDLER( mermaid_colorram_w )
{
colorram[offset] = data;
tilemap_mark_tile_dirty(fg_tilemap, offset);
}
WRITE8_HANDLER( mermaid_flip_screen_x_w )
{
flip_screen_x_set(data & 0x01);
}
WRITE8_HANDLER( mermaid_flip_screen_y_w )
{
flip_screen_y_set(data & 0x01);
}
WRITE8_HANDLER( mermaid_bg_scroll_w )
{
mermaid_bg_scrollram[offset] = data;
tilemap_set_scrolly(bg_tilemap, offset, data);
}
WRITE8_HANDLER( mermaid_fg_scroll_w )
{
mermaid_fg_scrollram[offset] = data;
tilemap_set_scrolly(fg_tilemap, offset, data);
}
WRITE8_HANDLER( rougien_gfxbankswitch1_w )
{
rougien_gfxbank1 = data & 0x01;
}
WRITE8_HANDLER( rougien_gfxbankswitch2_w )
{
rougien_gfxbank2 = data & 0x01;
}
READ8_HANDLER( mermaid_collision_r )
{
/*
collision register active LO
Bit 0
Bit 1 - Sprite - Foreground
Bit 2 - Sprite - Stream
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
*/
return 0; // not implemented
}
static TILE_GET_INFO( get_bg_tile_info )
{
int code = mermaid_videoram2[tile_index];
int sx = tile_index % 32;
int color = (sx >= 26) ? 0 : 1;
SET_TILE_INFO(2, code, color, 0);
}
static TILE_GET_INFO( get_fg_tile_info )
{
int attr = colorram[tile_index];
int code = videoram[tile_index] + ((attr & 0x30) << 4);
int color = attr & 0x0f;
int flags = TILE_FLIPYX((attr & 0xc0) >> 6);
code |= rougien_gfxbank1 * 0x2800;
code |= rougien_gfxbank2 * 0x2400;
SET_TILE_INFO(0, code, color, flags);
}
VIDEO_START( mermaid )
{
bg_tilemap = tilemap_create(get_bg_tile_info, tilemap_scan_rows,
TILEMAP_TYPE_PEN, 8, 8, 32, 32);
fg_tilemap = tilemap_create(get_fg_tile_info, tilemap_scan_rows,
TILEMAP_TYPE_PEN, 8, 8, 32, 32);
tilemap_set_scroll_cols(bg_tilemap, 32);
tilemap_set_scroll_cols(fg_tilemap, 32);
tilemap_set_transparent_pen(fg_tilemap, 0);
}
static void draw_sprites(running_machine *machine, mame_bitmap *bitmap, const rectangle *cliprect)
{
int offs;
for (offs = spriteram_size - 4; offs >= 0; offs -= 4)
{
int attr = spriteram[offs + 2];
int bank = (attr & 0x30) >> 4;
int code = (spriteram[offs] & 0x3f) | (bank << 6);
int color = attr & 0x0f;
int flipx = spriteram[offs] & 0x40;
int flipy = spriteram[offs] & 0x80;
int sx = spriteram[offs + 3] + 1;
int sy = 240 - spriteram[offs + 1];
code |= rougien_gfxbank1 * 0x2800;
code |= rougien_gfxbank2 * 0x2400;
if (flip_screen_x)
{
flipx = !flipx;
sx = 240 - sx;
}
if (flip_screen_y)
{
flipy = !flipy;
sy = 240 - sy;
}
drawgfx(bitmap, machine->gfx[1], code, color, flipx, flipy, sx, sy,
(flip_screen_x ? &flip_spritevisiblearea : &spritevisiblearea),
TRANSPARENCY_PEN, 0);
}
}
VIDEO_UPDATE( mermaid )
{
tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0);
tilemap_draw(bitmap, cliprect, fg_tilemap, 0, 0);
draw_sprites(machine, bitmap, cliprect);
return 0;
}