summaryrefslogblamecommitdiffstatshomepage
path: root/src/mame/video/1943.cpp
blob: 1138368d52f828e1490f5e70eab231b2f8eb916b (plain) (tree)
1
2
                       
                                




























                                                                            
                
                          














                                                                            
 
                                     
 
                                                               

              
                                   
         

                                           

                                   



                                                           

                                                                          
                                     



                                                           

                                                                          
                                    



                                                           

                                                                          
                                                              







                                                                        
                                                                  
                                                       




                                                   
                                                                                     
                                                                                                        
                                                       




                                                        
                                                                                     
                                                                                                        
                                                       


                                       

                                                                   

                                       
                                                                                     
                                                                                                               
                                                       
         

 
                                            
 

                                              

 
                                            
 

                                              

 
                                        
 
                                            

                                                               

                                                 
                                                        



                                                       
                                     

                                      
                                

 
                                        

                                
                               

                                
                               

                                   
                               

 
                                                          
 
                                                              






                                                    
                                                    

 
                                                         
 
                                                     






                                                        
                               
                                                    

 
                                                         
 

                                                                 

                                
                                                

 
                               
 


                                                                                                                                                                                  
 
                                                                   
                                             
 



                                   

 
                                                                                               


                 
                                                                    
         

                                                                    
                                        

                                                                      
 
                                  








                                                                          
                                                                                                                                     



                                                           
                                                                                                                                     



                 
                                                                                                                
 


                                                                             
 
                     
                                                                    
            
                                                              
 
                     
                                                  
 
                     
                                                                   
 
                     
                                                  
 
                      
                                                                   
 

                 
// license:BSD-3-Clause
// copyright-holders:Paul Leaman
/***************************************************************************

1943 Video Hardware

This board handles tile/tile and tile/sprite priority with a PROM. Its
working is hardcoded in the driver.

The PROM have address inputs wired as follows:

A0 bg (SCR) opaque
A1 bit 2 of sprite (OBJ) attribute (guess)
A2 bit 3 of sprite (OBJ) attribute (guess)
A3 sprite (OBJ) opaque
A4 fg (CHAR) opaque
A5 wired to mass
A6 wired to mass
A7 wired to mass

2 bits of the output selects the active layer, it can be:
(output & 0x03)
0 bg2 (SCR2)
1 bg (SCR)
2 sprite (OBJ)
3 fg (CHAR)

other 2 bits (output & 0x0c) unknown

***************************************************************************/

#include "emu.h"
#include "includes/1943.h"

/***************************************************************************

  Convert the color PROMs into a more useable format.

  1943 has three 256x4 palette PROMs (one per gun) and a lot ;-) of 256x4
  lookup table PROMs.
  The palette PROMs are connected to the RGB output this way:

  bit 3 -- 220 ohm resistor  -- RED/GREEN/BLUE
        -- 470 ohm resistor  -- RED/GREEN/BLUE
        -- 1  kohm resistor  -- RED/GREEN/BLUE
  bit 0 -- 2.2kohm resistor  -- RED/GREEN/BLUE

***************************************************************************/

PALETTE_INIT_MEMBER(_1943_state,1943)
{
	const uint8_t *color_prom = memregion("proms")->base();
	int i;

	for (i = 0; i < 0x100; i++)
	{
		int bit0, bit1, bit2, bit3;
		int r, g, b;

		/* red component */
		bit0 = (color_prom[i + 0x000] >> 0) & 0x01;
		bit1 = (color_prom[i + 0x000] >> 1) & 0x01;
		bit2 = (color_prom[i + 0x000] >> 2) & 0x01;
		bit3 = (color_prom[i + 0x000] >> 3) & 0x01;
		r = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		/* green component */
		bit0 = (color_prom[i + 0x100] >> 0) & 0x01;
		bit1 = (color_prom[i + 0x100] >> 1) & 0x01;
		bit2 = (color_prom[i + 0x100] >> 2) & 0x01;
		bit3 = (color_prom[i + 0x100] >> 3) & 0x01;
		g = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * bit3;

		/* blue component */
		bit0 = (color_prom[i + 0x200] >> 0) & 0x01;
		bit1 = (color_prom[i + 0x200] >> 1) & 0x01;
		bit2 = (color_prom[i + 0x200] >> 2) & 0x01;
		bit3 = (color_prom[i + 0x200] >> 3) & 0x01;
		b = 0x0e * bit0 + 0x1f * bit1 + 0x43 * bit2 + 0x8f * 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 0x40-0x4f */
	for (i = 0x00; i < 0x80; i++)
	{
		uint8_t ctabentry = (color_prom[i] & 0x0f) | 0x40;
		palette.set_pen_indirect(i, ctabentry);
	}

	/* foreground tiles use colors 0x00-0x3f */
	for (i = 0x80; i < 0x180; i++)
	{
		uint8_t ctabentry = ((color_prom[0x200 + (i - 0x080)] & 0x03) << 4) |
							((color_prom[0x100 + (i - 0x080)] & 0x0f) << 0);
		palette.set_pen_indirect(i, ctabentry);
	}

	/* background tiles also use colors 0x00-0x3f */
	for (i = 0x180; i < 0x280; i++)
	{
		uint8_t ctabentry = ((color_prom[0x400 + (i - 0x180)] & 0x03) << 4) |
							((color_prom[0x300 + (i - 0x180)] & 0x0f) << 0);
		palette.set_pen_indirect(i, ctabentry);
	}

	/* sprites use colors 0x80-0xff
	   bit 3 of BMPROM.07 selects priority over the background,
	   but we handle it differently for speed reasons */
	for (i = 0x280; i < 0x380; i++)
	{
		uint8_t ctabentry = ((color_prom[0x600 + (i - 0x280)] & 0x07) << 4) |
							((color_prom[0x500 + (i - 0x280)] & 0x0f) << 0) | 0x80;
		palette.set_pen_indirect(i, ctabentry);
	}
}

WRITE8_MEMBER(_1943_state::c1943_videoram_w)
{
	m_videoram[offset] = data;
	m_fg_tilemap->mark_tile_dirty(offset);
}

WRITE8_MEMBER(_1943_state::c1943_colorram_w)
{
	m_colorram[offset] = data;
	m_fg_tilemap->mark_tile_dirty(offset);
}

WRITE8_MEMBER(_1943_state::c1943_c804_w)
{
	/* bits 0 and 1 are coin counters */
	machine().bookkeeping().coin_counter_w(0, data & 0x01);
	machine().bookkeeping().coin_counter_w(1, data & 0x02);

	/* bits 2, 3 and 4 select the ROM bank */
	membank("bank1")->set_entry((data & 0x1c) >> 2);

	/* bit 5 resets the sound CPU - we ignore it */

	/* bit 6 flips screen */
	flip_screen_set(data & 0x40);

	/* bit 7 enables characters */
	m_char_on = data & 0x80;
}

WRITE8_MEMBER(_1943_state::c1943_d806_w)
{
	/* bit 4 enables bg 1 */
	m_bg1_on = data & 0x10;

	/* bit 5 enables bg 2 */
	m_bg2_on = data & 0x20;

	/* bit 6 enables sprites */
	m_obj_on = data & 0x40;
}

TILE_GET_INFO_MEMBER(_1943_state::c1943_get_bg2_tile_info)
{
	uint8_t *tilerom = memregion("gfx5")->base() + 0x8000;

	int offs = tile_index * 2;
	int attr = tilerom[offs + 1];
	int code = tilerom[offs];
	int color = (attr & 0x3c) >> 2;
	int flags = TILE_FLIPYX((attr & 0xc0) >> 6);

	SET_TILE_INFO_MEMBER(2, code, color, flags);
}

TILE_GET_INFO_MEMBER(_1943_state::c1943_get_bg_tile_info)
{
	uint8_t *tilerom = memregion("gfx5")->base();

	int offs = tile_index * 2;
	int attr = tilerom[offs + 1];
	int code = tilerom[offs] + ((attr & 0x01) << 8);
	int color = (attr & 0x3c) >> 2;
	int flags = TILE_FLIPYX((attr & 0xc0) >> 6);

	tileinfo.group = color;
	SET_TILE_INFO_MEMBER(1, code, color, flags);
}

TILE_GET_INFO_MEMBER(_1943_state::c1943_get_fg_tile_info)
{
	int attr = m_colorram[tile_index];
	int code = m_videoram[tile_index] + ((attr & 0xe0) << 3);
	int color = attr & 0x1f;

	SET_TILE_INFO_MEMBER(0, code, color, 0);
}

void _1943_state::video_start()
{
	m_bg2_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(FUNC(_1943_state::c1943_get_bg2_tile_info),this), TILEMAP_SCAN_COLS, 32, 32, 2048, 8);
	m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(FUNC(_1943_state::c1943_get_bg_tile_info),this), TILEMAP_SCAN_COLS, 32, 32, 2048, 8);
	m_fg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(FUNC(_1943_state::c1943_get_fg_tile_info),this), TILEMAP_SCAN_ROWS, 8, 8, 32, 32);

	m_bg_tilemap->configure_groups(*m_gfxdecode->gfx(1), 0x0f);
	m_fg_tilemap->set_transparent_pen(0);

	save_item(NAME(m_char_on));
	save_item(NAME(m_obj_on));
	save_item(NAME(m_bg1_on));
	save_item(NAME(m_bg2_on));
}

void _1943_state::draw_sprites( bitmap_ind16 &bitmap, const rectangle &cliprect, int priority )
{
	int offs;

	for (offs = m_spriteram.bytes() - 32; offs >= 0; offs -= 32)
	{
		int attr = m_spriteram[offs + 1];
		int code = m_spriteram[offs] + ((attr & 0xe0) << 3);
		int color = attr & 0x0f;
		int sx = m_spriteram[offs + 3] - ((attr & 0x10) << 4);
		int sy = m_spriteram[offs + 2];

		if (flip_screen())
		{
			sx = 240 - sx;
			sy = 240 - sy;
		}

		// the priority is actually selected by bit 3 of BMPROM.07
		if (priority)
		{
			if (color != 0x0a && color != 0x0b)
				m_gfxdecode->gfx(3)->transpen(bitmap,cliprect, code, color, flip_screen(), flip_screen(), sx, sy, 0);
		}
		else
		{
			if (color == 0x0a || color == 0x0b)
				m_gfxdecode->gfx(3)->transpen(bitmap,cliprect, code, color, flip_screen(), flip_screen(), sx, sy, 0);
		}
	}
}

uint32_t _1943_state::screen_update_1943(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
	m_bg2_tilemap->set_scrollx(0, m_bgscrollx[0] + 256 * m_bgscrollx[1]);
	m_bg_tilemap->set_scrollx(0, m_scrollx[0] + 256 * m_scrollx[1]);
	m_bg_tilemap->set_scrolly(0, m_scrolly[0]);

	if (m_bg2_on)
		m_bg2_tilemap->draw(screen, bitmap, cliprect, 0, 0);
	else
		bitmap.fill(m_palette->black_pen(), cliprect);

	if (m_obj_on)
		draw_sprites(bitmap, cliprect, 0);

	if (m_bg1_on)
		m_bg_tilemap->draw(screen, bitmap, cliprect, 0, 0);

	if (m_obj_on)
		draw_sprites(bitmap, cliprect, 1);

	if (m_char_on)
		m_fg_tilemap->draw(screen, bitmap, cliprect, 0, 0);

	return 0;
}