// license:BSD-3-Clause
// copyright-holders:Aaron Giles
/***************************************************************************
Atari GX2 hardware
*****************************************************************************
MO data has 12 bits total: MVID0-11
MVID9-11 form the priority
MVID0-9 form the color bits
PF data has 13 bits total: PF.VID0-12
PF.VID10-12 form the priority
PF.VID0-9 form the color bits
Upper bits come from the low 5 bits of the HSCROLL value in alpha RAM
Playfield bank comes from low 2 bits of the VSCROLL value in alpha RAM
For GX2, there are 4 bits of bank1
****************************************************************************/
#include "emu.h"
#include "video/atarirle.h"
#include "includes/atarigx2.h"
/*************************************
*
* Tilemap callbacks
*
*************************************/
TILE_GET_INFO_MEMBER(atarigx2_state::get_alpha_tile_info)
{
uint16_t data = m_alpha_tilemap->basemem_read(tile_index);
int code = data & 0xfff;
int color = (data >> 12) & 0x0f;
int opaque = data & 0x8000;
SET_TILE_INFO_MEMBER(1, code, color, opaque ? TILE_FORCE_LAYER0 : 0);
}
TILE_GET_INFO_MEMBER(atarigx2_state::get_playfield_tile_info)
{
uint16_t data = m_playfield_tilemap->basemem_read(tile_index);
int code = (m_playfield_tile_bank << 12) | (data & 0xfff);
int color = (m_playfield_base >> 5) + ((m_playfield_color_bank << 3) & 0x18) + ((data >> 12) & 7);
SET_TILE_INFO_MEMBER(0, code, color, (data >> 15) & 1);
tileinfo.category = (m_playfield_color_bank >> 2) & 7;
}
TILEMAP_MAPPER_MEMBER(atarigx2_state::atarigx2_playfield_scan)
{
int bank = 1 - (col / (num_cols / 2));
return bank * (num_rows * num_cols / 2) + row * (num_cols / 2) + (col % (num_cols / 2));
}
/*************************************
*
* Video system start
*
*************************************/
void atarigx2_state::video_start()
{
/* blend the playfields and free the temporary one */
blend_gfx(0, 2, 0x0f, 0x30);
/* save states */
save_item(NAME(m_current_control));
save_item(NAME(m_playfield_tile_bank));
save_item(NAME(m_playfield_color_bank));
save_item(NAME(m_playfield_xscroll));
save_item(NAME(m_playfield_yscroll));
}
/*************************************
*
* Periodic scanline updater
*
*************************************/
WRITE16_MEMBER( atarigx2_state::atarigx2_mo_control_w )
{
logerror("MOCONT = %d (scan = %d)\n", data, m_screen->vpos());
/* set the control value */
COMBINE_DATA(&m_current_control);
}
void atarigx2_state::scanline_update(screen_device &screen, int scanline)
{
int i;
if (scanline == 0) logerror("-------\n");
/* keep in range */
int offset = (scanline / 8) * 64 + 48;
if (offset >= 0x800)
return;
/* update the playfield scrolls */
for (i = 0; i < 8; i++)
{
uint16_t word = m_alpha_tilemap->basemem_read(offset++);
if (word & 0x8000)
{
int newscroll = (word >> 5) & 0x3ff;
int newbank = (word >> 0) & 0x1f;
if (newscroll != m_playfield_xscroll)
{
if (scanline + i > 0)
screen.update_partial(scanline + i - 1);
m_playfield_tilemap->set_scrollx(0, newscroll);
m_playfield_xscroll = newscroll;
}
if (newbank != m_playfield_color_bank)
{
if (scanline + i > 0)
screen.update_partial(scanline + i - 1);
m_playfield_tilemap->mark_all_dirty();
m_playfield_color_bank = newbank;
}
}
word = m_alpha_tilemap->basemem_read(offset++);
if (word & 0x8000)
{
int newscroll = ((word >> 6) - (scanline + i)) & 0x1ff;
int newbank = word & 15;
if (newscroll != m_playfield_yscroll)
{
if (scanline + i > 0)
screen.update_partial(scanline + i - 1);
m_playfield_tilemap->set_scrolly(0, newscroll);
m_playfield_yscroll = newscroll;
}
if (newbank != m_playfield_tile_bank)
{
if (scanline + i > 0)
screen.update_partial(scanline + i - 1);
m_playfield_tilemap->mark_all_dirty();
m_playfield_tile_bank = newbank;
}
}
}
}
/*************************************
*
* Main refresh
*
*************************************/
uint32_t atarigx2_state::screen_update_atarigx2(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
bitmap_ind8 &priority_bitmap = screen.priority();
/* draw the playfield */
priority_bitmap.fill(0, cliprect);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 0, 0);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 1, 1);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 2, 2);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 3, 3);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 4, 4);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 5, 5);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 6, 6);
m_playfield_tilemap->draw(screen, bitmap, cliprect, 7, 7);
/* copy the motion objects on top */
{
bitmap_ind16 &mo_bitmap = m_rle->vram(0);
int left = cliprect.min_x;
int top = cliprect.min_y;
int right = cliprect.max_x + 1;
int bottom = cliprect.max_y + 1;
int x, y;
/* now blend with the playfield */
for (y = top; y < bottom; y++)
{
uint16_t *pf = &bitmap.pix16(y);
uint16_t *mo = &mo_bitmap.pix16(y);
uint8_t *pri = &priority_bitmap.pix8(y);
for (x = left; x < right; x++)
if (mo[x] && (mo[x] >> ATARIRLE_PRIORITY_SHIFT) >= pri[x])
pf[x] = mo[x] & ATARIRLE_DATA_MASK;
}
}
/* add the alpha on top */
m_alpha_tilemap->draw(screen, bitmap, cliprect, 0, 0);
return 0;
}