// license:BSD-3-Clause // copyright-holders:Mirko Buffoni /*************************************************************************** video.c Functions to emulate the video hardware of the machine. ***************************************************************************/ #include "emu.h" #include "includes/citycon.h" /*************************************************************************** Callbacks for the TileMap code ***************************************************************************/ TILEMAP_MAPPER_MEMBER(citycon_state::citycon_scan) { /* logical (col,row) -> memory offset */ return (col & 0x1f) + ((row & 0x1f) << 5) + ((col & 0x60) << 5); } TILE_GET_INFO_MEMBER(citycon_state::get_fg_tile_info) { SET_TILE_INFO_MEMBER(0, m_videoram[tile_index], (tile_index & 0x03e0) >> 5, /* color depends on scanline only */ 0); } TILE_GET_INFO_MEMBER(citycon_state::get_bg_tile_info) { uint8_t *rom = memregion("gfx4")->base(); int code = rom[0x1000 * m_bg_image + tile_index]; SET_TILE_INFO_MEMBER(3 + m_bg_image, code, rom[0xc000 + 0x100 * m_bg_image + code], 0); } /*************************************************************************** Start the video hardware emulation. ***************************************************************************/ void citycon_state::video_start() { m_fg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(citycon_state::get_fg_tile_info)), tilemap_mapper_delegate(*this, FUNC(citycon_state::citycon_scan)), 8, 8, 128, 32); m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(citycon_state::get_bg_tile_info)), tilemap_mapper_delegate(*this, FUNC(citycon_state::citycon_scan)), 8, 8, 128, 32); m_fg_tilemap->set_transparent_pen(0); m_fg_tilemap->set_scroll_rows(32); } /*************************************************************************** Memory handlers ***************************************************************************/ WRITE8_MEMBER(citycon_state::citycon_videoram_w) { m_videoram[offset] = data; m_fg_tilemap->mark_tile_dirty(offset); } WRITE8_MEMBER(citycon_state::citycon_linecolor_w) { m_linecolor[offset] = data; } WRITE8_MEMBER(citycon_state::citycon_background_w) { /* bits 4-7 control the background image */ if (m_bg_image != (data >> 4)) { m_bg_image = (data >> 4); m_bg_tilemap->mark_all_dirty(); } /* bit 0 flips screen */ /* it is also used to multiplex player 1 and player 2 controls */ flip_screen_set(data & 0x01); /* bits 1-3 are unknown */ // if ((data & 0x0e) != 0) logerror("background register = %02x\n", data); } void citycon_state::draw_sprites( bitmap_ind16 &bitmap, const rectangle &cliprect ) { int offs; for (offs = m_spriteram.bytes() - 4; offs >= 0; offs -= 4) { int sx, sy, flipx; sx = m_spriteram[offs + 3]; sy = 239 - m_spriteram[offs]; flipx = ~m_spriteram[offs + 2] & 0x10; if (flip_screen()) { sx = 240 - sx; sy = 238 - sy; flipx = !flipx; } m_gfxdecode->gfx(m_spriteram[offs + 1] & 0x80 ? 2 : 1)->transpen(bitmap,cliprect, m_spriteram[offs + 1] & 0x7f, m_spriteram[offs + 2] & 0x0f, flipx,flip_screen(), sx, sy, 0); } } inline void citycon_state::changecolor_RRRRGGGGBBBBxxxx( int color, int indx ) { int data = m_palette->basemem().read8(2 * indx | 1) | (m_palette->basemem().read8(2 * indx) << 8); m_palette->set_pen_color(color, pal4bit(data >> 12), pal4bit(data >> 8), pal4bit(data >> 4)); } uint32_t citycon_state::screen_update_citycon(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect) { int offs, scroll; /* Update the virtual palette to support text color code changing on every scanline. */ for (offs = 0; offs < 256; offs++) { int indx = m_linecolor[offs]; int i; for (i = 0; i < 4; i++) changecolor_RRRRGGGGBBBBxxxx(640 + 4 * offs + i, 512 + 4 * indx + i); } scroll = m_scroll[0] * 256 + m_scroll[1]; m_bg_tilemap->set_scrollx(0, scroll >> 1); for (offs = 6; offs < 32; offs++) m_fg_tilemap->set_scrollx(offs, scroll); m_bg_tilemap->draw(screen, bitmap, cliprect, 0, 0); m_fg_tilemap->draw(screen, bitmap, cliprect, 0, 0); draw_sprites(bitmap, cliprect); return 0; }