// license:BSD-3-Clause
// copyright-holders:Aaron Giles
/***************************************************************************
Atari "Round" hardware
****************************************************************************/
#include "emu.h"
#include "machine/atarigen.h"
#include "includes/relief.h"
/*************************************
*
* Tilemap callbacks
*
*************************************/
TILE_GET_INFO_MEMBER(relief_state::get_playfield_tile_info)
{
uint16_t data1 = m_vad->playfield().basemem_read(tile_index);
uint16_t data2 = m_vad->playfield().extmem_read(tile_index) & 0xff;
int code = data1 & 0x7fff;
int color = 0x20 + (data2 & 0x0f);
SET_TILE_INFO_MEMBER(0, code, color, (data1 >> 15) & 1);
}
TILE_GET_INFO_MEMBER(relief_state::get_playfield2_tile_info)
{
uint16_t data1 = m_vad->playfield2().basemem_read(tile_index);
uint16_t data2 = m_vad->playfield2().extmem_read(tile_index) >> 8;
int code = data1 & 0x7fff;
int color = data2 & 0x0f;
SET_TILE_INFO_MEMBER(0, code, color, (data1 >> 15) & 1);
}
/*************************************
*
* Video system start
*
*************************************/
const atari_motion_objects_config relief_state::s_mob_config =
{
1, /* index to which gfx system */
1, /* number of motion object banks */
1, /* are the entries linked? */
0, /* are the entries split? */
0, /* render in reverse order? */
0, /* render in swapped X/Y order? */
0, /* does the neighbor bit affect the next object? */
8, /* pixels per SLIP entry (0 for no-slip) */
0, /* pixel offset for SLIPs */
0, /* maximum number of links to visit/scanline (0=all) */
0x100, /* base palette entry */
0x100, /* maximum number of colors */
0, /* transparent pen index */
{{ 0x00ff,0,0,0 }}, /* mask for the link */
{{ 0,0x7fff,0,0 }}, /* mask for the code index */
{{ 0,0,0x000f,0 }}, /* mask for the color */
{{ 0,0,0xff80,0 }}, /* mask for the X position */
{{ 0,0,0,0xff80 }}, /* mask for the Y position */
{{ 0,0,0,0x0070 }}, /* mask for the width, in tiles*/
{{ 0,0,0,0x0007 }}, /* mask for the height, in tiles */
{{ 0,0x8000,0,0 }}, /* mask for the horizontal flip */
{{ 0 }}, /* mask for the vertical flip */
{{ 0 }}, /* mask for the priority */
{{ 0 }}, /* mask for the neighbor */
{{ 0 }}, /* mask for absolute coordinates */
{{ 0 }}, /* mask for the special value */
0 /* resulting value to indicate "special" */
};
void relief_state::video_start()
{
/* MOs are 5bpp but with a 4-bit color granularity */
m_gfxdecode->gfx(1)->set_granularity(16);
}
/*************************************
*
* Main refresh
*
*************************************/
uint32_t relief_state::screen_update_relief(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
// start drawing
m_vad->mob().draw_async(cliprect);
/* draw the playfield */
bitmap_ind8 &priority_bitmap = screen.priority();
priority_bitmap.fill(0, cliprect);
m_vad->playfield().draw(screen, bitmap, cliprect, 0, 0);
m_vad->playfield2().draw(screen, bitmap, cliprect, 0, 1);
// draw and merge the MO
bitmap_ind16 &mobitmap = m_vad->mob().bitmap();
for (const sparse_dirty_rect *rect = m_vad->mob().first_dirty_rect(cliprect); rect != nullptr; rect = rect->next())
for (int y = rect->min_y; y <= rect->max_y; y++)
{
uint16_t *mo = &mobitmap.pix16(y);
uint16_t *pf = &bitmap.pix16(y);
uint8_t *pri = &priority_bitmap.pix8(y);
for (int x = rect->min_x; x <= rect->max_x; x++)
if (mo[x] != 0xffff)
{
/* verified from the GALs on the real PCB; equations follow
*
* --- PF/M is 1 if playfield has priority, or 0 if MOs have priority
* PF/M = PFXS
*
* --- CS0 is set to 1 if the MO is transparent
* CS0=!MPX0*!MPX1*!MPX2*!MPX3
*
* --- CS1 is 1 to select playfield pixels or 0 to select MO pixels
* !CS1=MPX5*MPX6*MPX7*!CS0
* +!MPX4*MPX5*MPX6*MPX7
* +PFXS*!CS0
* +!MPX4*PFXS
*
* --- CRA10 is the 0x200 bit of the color RAM index; set for the top playfield only
* CRA10:=CS1*PFXS
*
* --- CRA9 is the 0x100 bit of the color RAM index; set for MOs only
* !CA9:=CS1
*
* --- CRA8-1 are the low 8 bits of the color RAM index; set as expected
*/
int cs0 = 0;
int cs1 = 1;
/* compute the CS0 signal */
cs0 = ((mo[x] & 0x0f) == 0);
/* compute the CS1 signal */
if ((!cs0 && (mo[x] & 0xe0) == 0xe0) ||
((mo[x] & 0xf0) == 0xe0) ||
(!pri[x] && !cs0) ||
(!pri[x] && !(mo[x] & 0x10)))
cs1 = 0;
/* MO is displayed if cs1 == 0 */
if (!cs1)
pf[x] = mo[x];
}
}
return 0;
}