// license:BSD-3-Clause
// copyright-holders:Carlos A. Lozano
/***************************************************************************
video.c
Functions to emulate the video hardware of the machine.
***************************************************************************/
#include "emu.h"
#include "includes/cop01.h"
void cop01_state::cop01_palette(palette_device &palette) const
{
const uint8_t *color_prom = memregion("proms")->base();
// create a lookup table for the palette
for (int i = 0; i < 0x100; i++)
{
int const r = pal4bit(color_prom[i + 0x000]);
int const g = pal4bit(color_prom[i + 0x100]);
int const b = pal4bit(color_prom[i + 0x200]);
palette.set_indirect_color(i, rgb_t(r, g, b));
}
// color_prom now points to the beginning of the lookup table
color_prom += 0x300;
// characters use colors 0x00-0x0f (or 0x00-0x7f, but the eight rows are identical)
for (int i = 0; i < 0x10; i++)
palette.set_pen_indirect(i, i);
// background tiles use colors 0xc0-0xff
// I don't know how much of the lookup table PROM is hooked up,
// I'm only using the first 32 bytes because the rest is empty.
for (int i = 0; i < 0x80; i++)
{
uint8_t const ctabentry = 0xc0 | (i & 0x30) | (color_prom[((i & 0x40) >> 2) | (i & 0x0f)] & 0x0f);
palette.set_pen_indirect(i + 0x10, ctabentry);
}
// sprites use colors 0x80-0x8f (or 0x80-0xbf, but the four rows are identical)
for (int i = 0; i < 0x100; i++)
{
uint8_t ctabentry = 0x80 | (color_prom[i + 0x100] & 0x0f);
palette.set_pen_indirect(i + 0x90, ctabentry);
}
}
/***************************************************************************
Callbacks for the TileMap code
***************************************************************************/
TILE_GET_INFO_MEMBER(cop01_state::get_bg_tile_info)
{
int tile = m_bgvideoram[tile_index];
int attr = m_bgvideoram[tile_index + 0x800];
int pri = (attr & 0x80) >> 7;
/* kludge: priority is not actually pen based, but color based. Since the
* game uses a lookup table, the two are not the same thing.
* Palette entries with bits 2&3 set have priority over sprites.
* tilemap.c can't handle that yet, so I'm cheating, because I know that
* color codes using the second row of the lookup table don't use palette
* entries 12-15.
* The only place where this has any effect is the beach at the bottom of
* the screen right at the beginning of mightguy. cop01 doesn't seem to
* use priority at all.
*/
if (attr & 0x10)
pri = 0;
SET_TILE_INFO_MEMBER(1, tile + ((attr & 0x03) << 8), (attr & 0x1c) >> 2, 0);
tileinfo.group = pri;
}
TILE_GET_INFO_MEMBER(cop01_state::get_fg_tile_info)
{
int tile = m_fgvideoram[tile_index];
SET_TILE_INFO_MEMBER(0, tile, 0, 0);
}
/***************************************************************************
Start the video hardware emulation.
***************************************************************************/
void cop01_state::video_start()
{
m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(cop01_state::get_bg_tile_info)), TILEMAP_SCAN_ROWS, 8, 8, 64, 32);
m_fg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(cop01_state::get_fg_tile_info)), TILEMAP_SCAN_ROWS, 8, 8, 32, 32);
m_fg_tilemap->set_transparent_pen(15);
/* priority doesn't exactly work this way, see above */
m_bg_tilemap->set_transmask(0, 0xffff, 0x0000); /* split type 0 is totally transparent in front half */
m_bg_tilemap->set_transmask(1, 0x0fff, 0xf000); /* split type 1 has pens 0-11 transparent in front half */
}
/***************************************************************************
Memory handlers
***************************************************************************/
WRITE8_MEMBER(cop01_state::cop01_background_w)
{
m_bgvideoram[offset] = data;
m_bg_tilemap->mark_tile_dirty(offset & 0x7ff);
}
WRITE8_MEMBER(cop01_state::cop01_foreground_w)
{
m_fgvideoram[offset] = data;
m_fg_tilemap->mark_tile_dirty(offset);
}
WRITE8_MEMBER(cop01_state::cop01_vreg_w)
{
/* 0x40: --xx---- sprite bank, coin counters, flip screen
* -----x-- flip screen
* ------xx coin counters
* 0x41: xxxxxxxx xscroll
* 0x42: ---xx--- ? matches the bg tile color most of the time, but not
* during level transitions. Maybe sprite palette bank?
* (the four banks in the PROM are identical)
* ------x- unused (xscroll overflow)
* -------x msb xscroll
* 0x43: xxxxxxxx yscroll
*/
m_vreg[offset] = data;
if (offset == 0)
{
machine().bookkeeping().coin_counter_w(0, data & 1);
machine().bookkeeping().coin_counter_w(1, data & 2);
flip_screen_set(data & 4);
}
}
/***************************************************************************
Display refresh
***************************************************************************/
void cop01_state::draw_sprites( bitmap_ind16 &bitmap, const rectangle &cliprect )
{
int offs, code, attr, sx, sy, flipx, flipy, color;
for (offs = 0; offs < m_spriteram.bytes(); offs += 4)
{
code = m_spriteram[offs + 1];
attr = m_spriteram[offs + 2];
/* xxxx---- color
* ----xx-- flipy,flipx
* -------x msbx
*/
color = attr>>4;
flipx = attr & 0x04;
flipy = attr & 0x08;
sx = (m_spriteram[offs + 3] - 0x80) + 256 * (attr & 0x01);
sy = 240 - m_spriteram[offs];
if (flip_screen())
{
sx = 240 - sx;
sy = 240 - sy;
flipx = !flipx;
flipy = !flipy;
}
if (code & 0x80)
code += (m_vreg[0] & 0x30) << 3;
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code,
color,
flipx,flipy,
sx,sy,0 );
}
}
uint32_t cop01_state::screen_update_cop01(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
m_bg_tilemap->set_scrollx(0, m_vreg[1] + 256 * (m_vreg[2] & 1));
m_bg_tilemap->set_scrolly(0, m_vreg[3]);
m_bg_tilemap->draw(screen, bitmap, cliprect, TILEMAP_DRAW_LAYER1, 0);
draw_sprites(bitmap, cliprect);
m_bg_tilemap->draw(screen, bitmap, cliprect, TILEMAP_DRAW_LAYER0, 0);
m_fg_tilemap->draw(screen, bitmap, cliprect, 0, 0 );
return 0;
}