// license:BSD-3-Clause
// copyright-holders:Nicola Salmoria
/***************************************************************************
bagman.c
Functions to emulate the video hardware of the machine.
***************************************************************************/
#include "emu.h"
#include "video/resnet.h"
#include "includes/bagman.h"
WRITE8_MEMBER(bagman_state::videoram_w)
{
m_videoram[offset] = data;
m_bg_tilemap->mark_tile_dirty(offset);
}
WRITE8_MEMBER(bagman_state::colorram_w)
{
m_colorram[offset] = data;
m_bg_tilemap->mark_tile_dirty(offset);
}
/***************************************************************************
Convert the color PROMs into a more useable format.
Bagman has two 32 bytes palette PROMs, connected to the RGB output this
way:
bit 7 -- 220 ohm resistor -- \
-- 470 ohm resistor -- | -- 470 ohm pulldown resistor -- BLUE
-- 220 ohm resistor -- \
-- 470 ohm resistor -- | -- 470 ohm pulldown resistor -- GREEN
-- 1 kohm resistor -- /
-- 220 ohm resistor -- \
-- 470 ohm resistor -- | -- 470 ohm pulldown resistor -- RED
bit 0 -- 1 kohm resistor -- /
***************************************************************************/
PALETTE_INIT_MEMBER(bagman_state,bagman)
{
const uint8_t *color_prom = memregion("proms")->base();
int i;
static const int resistances_rg[3] = { 1000, 470, 220 };
static const int resistances_b [2] = { 470, 220 };
double weights_r[3], weights_g[3], weights_b[2];
compute_resistor_weights(0, 255, -1.0,
3, resistances_rg, weights_r, 470, 0,
3, resistances_rg, weights_g, 470, 0,
2, resistances_b, weights_b, 470, 0);
for (i = 0; i < palette.entries(); i++)
{
int bit0, bit1, bit2, r, g, b;
/* red component */
bit0 = (color_prom[i] >> 0) & 0x01;
bit1 = (color_prom[i] >> 1) & 0x01;
bit2 = (color_prom[i] >> 2) & 0x01;
r = combine_3_weights(weights_r, bit0, bit1, bit2);
/* green component */
bit0 = (color_prom[i] >> 3) & 0x01;
bit1 = (color_prom[i] >> 4) & 0x01;
bit2 = (color_prom[i] >> 5) & 0x01;
g = combine_3_weights(weights_g, bit0, bit1, bit2);
/* blue component */
bit0 = (color_prom[i] >> 6) & 0x01;
bit1 = (color_prom[i] >> 7) & 0x01;
b = combine_2_weights(weights_b, bit0, bit1);
palette.set_pen_color(i,rgb_t(r,g,b));
}
}
WRITE_LINE_MEMBER(bagman_state::flipscreen_x_w)
{
flip_screen_x_set(state);
}
WRITE_LINE_MEMBER(bagman_state::flipscreen_y_w)
{
flip_screen_y_set(state);
}
WRITE_LINE_MEMBER(bagman_state::video_enable_w)
{
m_video_enable = state;
}
TILE_GET_INFO_MEMBER(bagman_state::get_bg_tile_info)
{
int gfxbank = (m_gfxdecode->gfx(2) && (m_colorram[tile_index] & 0x10)) ? 2 : 0;
int code = m_videoram[tile_index] + 8 * (m_colorram[tile_index] & 0x20);
int color = m_colorram[tile_index] & 0x0f;
SET_TILE_INFO_MEMBER(gfxbank, code, color, 0);
}
void bagman_state::video_start()
{
m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(FUNC(bagman_state::get_bg_tile_info),this), TILEMAP_SCAN_ROWS,
8, 8, 32, 32);
}
void bagman_state::draw_sprites(bitmap_ind16 &bitmap, const rectangle &cliprect)
{
for (int offs = m_spriteram.bytes() - 4;offs >= 0;offs -= 4)
{
int sx,sy,flipx,flipy;
sx = m_spriteram[offs + 3];
sy = 256 - m_spriteram[offs + 2] - 16;
flipx = m_spriteram[offs] & 0x40;
flipy = m_spriteram[offs] & 0x80;
if (flip_screen())
{
sx = 256 - sx - 15;
sy = 255 - sy - 15;
flipx = !flipx;
flipy = !flipy;
}
if (m_spriteram[offs + 2] && m_spriteram[offs + 3])
m_gfxdecode->gfx(1)->transpen(bitmap,
cliprect,
(m_spriteram[offs] & 0x3f) + 2 * (m_spriteram[offs + 1] & 0x20),
m_spriteram[offs + 1] & 0x1f,
flipx,flipy,
sx,sy,0);
}
}
uint32_t bagman_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
bitmap.fill(0, cliprect);
if (!m_video_enable)
return 0;
m_bg_tilemap->draw(screen, bitmap, cliprect, 0, 0);
draw_sprites(bitmap, cliprect);
return 0;
}