// license:BSD-3-Clause
// copyright-holders:Mirko Buffoni
/***************************************************************************
ironhors.c
Functions to emulate the video hardware of the machine.
***************************************************************************/
#include "emu.h"
#include "video/resnet.h"
#include "includes/ironhors.h"
/***************************************************************************
Convert the color PROMs into a more useable format.
***************************************************************************/
void ironhors_state::ironhors_palette(palette_device &palette) const
{
const uint8_t *color_prom = memregion("proms")->base();
static constexpr int resistances[4] = { 2000, 1000, 470, 220 };
// compute the color output resistor weights
double rweights[4], gweights[4], bweights[4];
compute_resistor_weights(0, 255, -1.0,
4, resistances, rweights, 1000, 0,
4, resistances, gweights, 1000, 0,
4, resistances, bweights, 1000, 0);
// create a lookup table for the palette
for (int i = 0; i < 0x100; i++)
{
int bit0, bit1, bit2, bit3;
// red component
bit0 = BIT(color_prom[i | 0x000], 0);
bit1 = BIT(color_prom[i | 0x000], 1);
bit2 = BIT(color_prom[i | 0x000], 2);
bit3 = BIT(color_prom[i | 0x000], 3);
int const r = combine_weights(rweights, bit0, bit1, bit2, bit3);
// green component
bit0 = BIT(color_prom[i | 0x100], 0);
bit1 = BIT(color_prom[i | 0x100], 1);
bit2 = BIT(color_prom[i | 0x100], 2);
bit3 = BIT(color_prom[i | 0x100], 3);
int const g = combine_weights(gweights, bit0, bit1, bit2, bit3);
// blue component
bit0 = BIT(color_prom[i | 0x200], 0);
bit1 = BIT(color_prom[i | 0x200], 1);
bit2 = BIT(color_prom[i | 0x200], 2);
bit3 = BIT(color_prom[i | 0x200], 3);
int const b = combine_weights(bweights, bit0, bit1, bit2, bit3);
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 0x10-0x1f of each 0x20 color bank, while sprites use colors 0-0x0f
for (int i = 0; i < 0x200; i++)
{
for (int j = 0; j < 8; j++)
{
uint8_t const ctabentry = (j << 5) | ((~i & 0x100) >> 4) | (color_prom[i] & 0x0f);
palette.set_pen_indirect(((i & 0x100) << 3) | (j << 8) | (i & 0xff), ctabentry);
}
}
}
WRITE8_MEMBER(ironhors_state::videoram_w)
{
m_videoram[offset] = data;
m_bg_tilemap->mark_tile_dirty(offset);
}
WRITE8_MEMBER(ironhors_state::colorram_w)
{
m_colorram[offset] = data;
m_bg_tilemap->mark_tile_dirty(offset);
}
WRITE8_MEMBER(ironhors_state::charbank_w)
{
if (m_charbank != (data & 0x03))
{
m_charbank = data & 0x03;
machine().tilemap().mark_all_dirty();
}
m_spriterambank = data & 0x08;
/* other bits unknown */
}
WRITE8_MEMBER(ironhors_state::palettebank_w)
{
if (m_palettebank != (data & 0x07))
{
m_palettebank = data & 0x07;
machine().tilemap().mark_all_dirty();
}
machine().bookkeeping().coin_counter_w(0, data & 0x10);
machine().bookkeeping().coin_counter_w(1, data & 0x20);
/* bit 6 unknown - set after game over */
if (data & 0x88)
popmessage("palettebank_w %02x",data);
}
WRITE8_MEMBER(ironhors_state::flipscreen_w)
{
if (flip_screen() != (~data & 0x08))
{
flip_screen_set(~data & 0x08);
machine().tilemap().mark_all_dirty();
}
/* other bits are used too, but unknown */
}
TILE_GET_INFO_MEMBER(ironhors_state::get_bg_tile_info)
{
int code = m_videoram[tile_index] + ((m_colorram[tile_index] & 0x40) << 2) +
((m_colorram[tile_index] & 0x20) << 4) + (m_charbank << 10);
int color = (m_colorram[tile_index] & 0x0f) + 16 * m_palettebank;
int flags = ((m_colorram[tile_index] & 0x10) ? TILE_FLIPX : 0) |
((m_colorram[tile_index] & 0x20) ? TILE_FLIPY : 0);
SET_TILE_INFO_MEMBER(0, code, color, flags);
}
void ironhors_state::video_start()
{
m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(ironhors_state::get_bg_tile_info)), TILEMAP_SCAN_ROWS, 8, 8, 32, 32);
m_bg_tilemap->set_scroll_rows(32);
}
void ironhors_state::draw_sprites( bitmap_ind16 &bitmap, const rectangle &cliprect )
{
int offs;
uint8_t *sr;
if (m_spriterambank != 0)
sr = m_spriteram;
else
sr = m_spriteram2;
for (offs = 0; offs < m_spriteram.bytes(); offs += 5)
{
int sx = sr[offs + 3];
int sy = sr[offs + 2];
int flipx = sr[offs + 4] & 0x20;
int flipy = sr[offs + 4] & 0x40;
int code = (sr[offs] << 2) + ((sr[offs + 1] & 0x03) << 10) + ((sr[offs + 1] & 0x0c) >> 2);
int color = ((sr[offs + 1] & 0xf0) >> 4) + 16 * m_palettebank;
// int mod = flip_screen() ? -8 : 8;
if (flip_screen())
{
sx = 240 - sx;
sy = 240 - sy;
flipx = !flipx;
flipy = !flipy;
}
switch (sr[offs + 4] & 0x0c)
{
case 0x00: /* 16x16 */
m_gfxdecode->gfx(1)->transpen(bitmap,cliprect,
code/4,
color,
flipx,flipy,
sx,sy,0);
break;
case 0x04: /* 16x8 */
{
if (flip_screen()) sy += 8; // this fixes the train wheels' position
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code & ~1,
color,
flipx,flipy,
flipx?sx+8:sx,sy,0);
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code | 1,
color,
flipx,flipy,
flipx?sx:sx+8,sy,0);
}
break;
case 0x08: /* 8x16 */
{
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code & ~2,
color,
flipx,flipy,
sx,flipy?sy+8:sy,0);
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code | 2,
color,
flipx,flipy,
sx,flipy?sy:sy+8,0);
}
break;
case 0x0c: /* 8x8 */
{
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code,
color,
flipx,flipy,
sx,sy,0);
}
break;
}
}
}
uint32_t ironhors_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
int row;
for (row = 0; row < 32; row++)
m_bg_tilemap->set_scrollx(row, m_scroll[row]);
m_bg_tilemap->draw(screen, bitmap, cliprect, 0, 0);
draw_sprites(bitmap, cliprect);
return 0;
}
TILE_GET_INFO_MEMBER(ironhors_state::farwest_get_bg_tile_info)
{
int code = m_videoram[tile_index] + ((m_colorram[tile_index] & 0x40) << 2) +
((m_colorram[tile_index] & 0x20) << 4) + (m_charbank << 10);
int color = (m_colorram[tile_index] & 0x0f) + 16 * m_palettebank;
int flags = 0;//((m_colorram[tile_index] & 0x10) ? TILE_FLIPX : 0) | ((m_colorram[tile_index] & 0x20) ? TILE_FLIPY : 0);
SET_TILE_INFO_MEMBER(0, code, color, flags);
}
VIDEO_START_MEMBER(ironhors_state,farwest)
{
m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(ironhors_state::farwest_get_bg_tile_info)), TILEMAP_SCAN_ROWS, 8, 8, 32, 32);
m_bg_tilemap->set_scroll_rows(32);
}
void ironhors_state::farwest_draw_sprites( bitmap_ind16 &bitmap, const rectangle &cliprect )
{
int offs;
uint8_t *sr = m_spriteram2;
uint8_t *sr2 = m_spriteram;
for (offs = 0; offs < m_spriteram.bytes(); offs += 4)
{
int sx = sr[offs + 2];
int sy = sr[offs + 1];
int flipx = sr[offs + 3] & 0x20;
int flipy = sr[offs + 3] & 0x40;
int code = (sr[offs] << 2) + ((sr2[offs] & 0x03) << 10) + ((sr2[offs] & 0x0c) >> 2);
int color = ((sr2[offs] & 0xf0) >> 4) + 16 * m_palettebank;
// int mod = flip_screen() ? -8 : 8;
// if (flip_screen())
{
// sx = 240 - sx;
sy = 240 - sy;
// flipx = !flipx;
// flipy = !flipy;
}
switch (sr[offs + 3] & 0x0c)
{
case 0x00: /* 16x16 */
m_gfxdecode->gfx(1)->transpen(bitmap,cliprect,
code/4,
color,
flipx,flipy,
sx,sy,0);
break;
case 0x04: /* 16x8 */
{
if (flip_screen()) sy += 8; // this fixes the train wheels' position
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code & ~1,
color,
flipx,flipy,
flipx?sx+8:sx,sy,0);
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code | 1,
color,
flipx,flipy,
flipx?sx:sx+8,sy,0);
}
break;
case 0x08: /* 8x16 */
{
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code & ~2,
color,
flipx,flipy,
sx,flipy?sy+8:sy,0);
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code | 2,
color,
flipx,flipy,
sx,flipy?sy:sy+8,0);
}
break;
case 0x0c: /* 8x8 */
{
m_gfxdecode->gfx(2)->transpen(bitmap,cliprect,
code,
color,
flipx,flipy,
sx,sy,0);
}
break;
}
}
}
uint32_t ironhors_state::screen_update_farwest(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
int row;
for (row = 0; row < 32; row++)
m_bg_tilemap->set_scrollx(row, m_scroll[row]);
m_bg_tilemap->draw(screen, bitmap, cliprect, 0, 0);
farwest_draw_sprites(bitmap, cliprect);
return 0;
}