// license:BSD-3-Clause
// copyright-holders:Manuel Abadia
/***************************************************************************
Target Hits Video Hardware
Functions to emulate the video hardware of the machine
***************************************************************************/
#include "emu.h"
#include "includes/targeth.h"
/***************************************************************************
Callbacks for the TileMap code
***************************************************************************/
/*
Tile format
-----------
Screen 0 & 1: (64*32, 16x16 tiles)
Word | Bit(s) | Description
-----+-FEDCBA98-76543210-+--------------------------
0 | --xxxxxx xxxxxxxx | code
0 | xx------ -------- | not used?
1 | -------- ---xxxxx | color (uses 1st half of the palette)
1 | -------- --x----- | flip y
1 | -------- -x------ | flip x
1 | xxxxxxxx x------- | not used?
*/
template<int Layer>
TILE_GET_INFO_MEMBER(targeth_state::get_tile_info)
{
int data = m_videoram[(Layer * 0x2000/2) + (tile_index << 1)];
int data2 = m_videoram[(Layer * 0x2000/2) + (tile_index << 1) + 1];
int code = data & 0x3fff;
SET_TILE_INFO_MEMBER(0, code, data2 & 0x1f, TILE_FLIPXY((data2 >> 5) & 0x03));
}
/***************************************************************************
Memory Handlers
***************************************************************************/
WRITE16_MEMBER(targeth_state::vram_w)
{
m_videoram[offset] = data;
m_pant[(offset & 0x1fff) >> 12]->mark_tile_dirty(((offset << 1) & 0x1fff) >> 2);
}
/***************************************************************************
Start/Stop the video hardware emulation.
***************************************************************************/
void targeth_state::video_start()
{
m_pant[0] = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(targeth_state::get_tile_info<0>)), TILEMAP_SCAN_ROWS, 16,16, 64,32);
m_pant[1] = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(*this, FUNC(targeth_state::get_tile_info<1>)), TILEMAP_SCAN_ROWS, 16,16, 64,32);
m_pant[0]->set_transparent_pen(0);
}
/***************************************************************************
Sprites
***************************************************************************/
/*
Sprite Format
-------------
Word | Bit(s) | Description
-----+-FEDCBA98-76543210-+--------------------------
0 | -------- xxxxxxxx | y position
0 | --xxxxxx -------- | not used?
0 | -x------ -------- | flipx
0 | x------- -------- | flipy
1 | xxxxxxxx xxxxxxxx | not used?
2 | ------xx xxxxxxxx | x position
2 | -xxxxx-- -------- | sprite color (uses 2nd half of the palette)
3 | --xxxxxx xxxxxxxx | sprite code
3 | xx------ -------- | not used?
*/
void targeth_state::draw_sprites(bitmap_ind16 &bitmap, const rectangle &cliprect)
{
gfx_element *gfx = m_gfxdecode->gfx(0);
for (int i = 3; i < (0x1000 - 6)/2; i += 4){
int sx = m_spriteram[i+2] & 0x03ff;
int sy = (240 - (m_spriteram[i] & 0x00ff)) & 0x00ff;
int number = m_spriteram[i+3] & 0x3fff;
int color = (m_spriteram[i+2] & 0x7c00) >> 10;
int attr = (m_spriteram[i] & 0xfe00) >> 9;
int xflip = attr & 0x20;
int yflip = attr & 0x40;
gfx->transpen(bitmap,cliprect,number,
0x20 + color,xflip,yflip,
sx - 0x0f,sy,0);
}
}
/***************************************************************************
Display Refresh
***************************************************************************/
uint32_t targeth_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
/* set scroll registers */
m_pant[0]->set_scrolly(0, m_vregs[0]);
m_pant[0]->set_scrollx(0, m_vregs[1] + 0x04);
m_pant[1]->set_scrolly(0, m_vregs[2]);
m_pant[1]->set_scrollx(0, m_vregs[3]);
m_pant[1]->draw(screen, bitmap, cliprect, 0,0);
m_pant[0]->draw(screen, bitmap, cliprect, 0,0);
draw_sprites(bitmap,cliprect);
return 0;
}