// license:LGPL-2.1+
// copyright-holders:Angelo Salese
/***************************************************************************
Device for Mazer Blazer/Great Guns custom Video Controller Unit
Written by Angelo Salese, based off old implementation by Jarek Burczynski
TODO:
- priority, especially noticeable in Great Guns sprites and Mazer Blazer
bonus stages;
- bit 0 of m_mode;
- first byte of parameter info;
- Glitchy UFO in Mazer Blazer when it's gonna zap one of the player lives, m_mode = 0xe and
it's supposed to be set into layer 0 somehow but this breaks Mazer Blazer title screen sparkles;
- Understand look-up tables in i/o space.
- Understand how to handle layer clearance (mostly done).
- Understand how planes are really handled (mostly done).
- Understand how transparent pens are handled aka is 0x0f always transparent or
there's some clut gimmick? Great Guns title screen makes me think of the
latter option;
- Mazer Blazer collision detection parameters are a complete guesswork
***************************************************************************/
#include "emu.h"
#include "video/mb_vcu.h"
#include "video/resnet.h"
//**************************************************************************
// GLOBAL VARIABLES
//**************************************************************************
// device type definition
DEFINE_DEVICE_TYPE(MB_VCU, mb_vcu_device, "mb_vcu", "Mazer Blazer custom VCU")
void mb_vcu_device::mb_vcu_vram(address_map &map)
{
if (!has_configured_map(0))
map(0x00000, 0x7ffff).ram(); // enough for a 256x256x4 x 2 pages of framebuffer with 4 layers (TODO: doubled for simplicity)
}
void mb_vcu_device::mb_vcu_pal_ram(address_map &map)
{
if (!has_configured_map(1))
{
map(0x0000, 0x00ff).ram();
map(0x0200, 0x02ff).ram();
map(0x0400, 0x04ff).ram();
map(0x0600, 0x06ff).rw(FUNC(mb_vcu_device::mb_vcu_paletteram_r), FUNC(mb_vcu_device::mb_vcu_paletteram_w));
}
}
READ8_MEMBER( mb_vcu_device::mb_vcu_paletteram_r )
{
return m_palram[offset];
}
WRITE8_MEMBER( mb_vcu_device::mb_vcu_paletteram_w )
{
int r,g,b, bit0, bit1, bit2;
m_palram[offset] = data;
/* red component */
bit1 = (m_palram[offset] >> 7) & 0x01;
bit0 = (m_palram[offset] >> 6) & 0x01;
r = combine_weights(m_weights_r, bit0, bit1);
/* green component */
bit2 = (m_palram[offset] >> 5) & 0x01;
bit1 = (m_palram[offset] >> 4) & 0x01;
bit0 = (m_palram[offset] >> 3) & 0x01;
g = combine_weights(m_weights_g, bit0, bit1, bit2);
/* blue component */
bit2 = (m_palram[offset] >> 2) & 0x01;
bit1 = (m_palram[offset] >> 1) & 0x01;
bit0 = (m_palram[offset] >> 0) & 0x01;
b = combine_weights(m_weights_b, bit0, bit1, bit2);
m_palette->set_pen_color(offset, rgb_t(r, g, b));
}
//-------------------------------------------------
// memory_space_config - return a description of
// any address spaces owned by this device
//-------------------------------------------------
device_memory_interface::space_config_vector mb_vcu_device::memory_space_config() const
{
return space_config_vector {
std::make_pair(0, &m_videoram_space_config),
std::make_pair(1, &m_paletteram_space_config)
};
}
//**************************************************************************
// INLINE HELPERS
//**************************************************************************
//-------------------------------------------------
// read_byte - read a byte at the given address
//-------------------------------------------------
inline uint8_t mb_vcu_device::read_byte(offs_t address)
{
return space(0).read_byte(address);
}
//-------------------------------------------------
// write_byte - write a byte at the given address
//-------------------------------------------------
inline void mb_vcu_device::write_byte(offs_t address, uint8_t data)
{
space(0).write_byte(address, data);
}
//-------------------------------------------------
// read_byte - read a byte at the given i/o
//-------------------------------------------------
inline uint8_t mb_vcu_device::read_io(offs_t address)
{
return space(1).read_byte(address);
}
//-------------------------------------------------
// write_byte - write a byte at the given i/o
//-------------------------------------------------
inline void mb_vcu_device::write_io(offs_t address, uint8_t data)
{
space(1).write_byte(address, data);
}
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
//-------------------------------------------------
// mb_vcu_device - constructor
//-------------------------------------------------
mb_vcu_device::mb_vcu_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, MB_VCU, tag, owner, clock)
, device_memory_interface(mconfig, *this)
, device_video_interface(mconfig, *this)
, m_videoram_space_config("videoram", ENDIANNESS_LITTLE, 8, 19, 0, address_map_constructor(FUNC(mb_vcu_device::mb_vcu_vram), this))
, m_paletteram_space_config("palram", ENDIANNESS_LITTLE, 8, 16, 0, address_map_constructor(FUNC(mb_vcu_device::mb_vcu_pal_ram), this))
, m_cpu(*this, finder_base::DUMMY_TAG)
, m_palette(*this, finder_base::DUMMY_TAG)
{
}
//-------------------------------------------------
// device_validity_check - perform validity checks
// on this device
//-------------------------------------------------
void mb_vcu_device::device_validity_check(validity_checker &valid) const
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void mb_vcu_device::device_start()
{
// TODO: m_screen_tag
m_ram = make_unique_clear<uint8_t[]>(0x800);
m_palram = make_unique_clear<uint8_t[]>(0x100);
{
static const int resistances_r[2] = { 4700, 2200 };
static const int resistances_gb[3] = { 10000, 4700, 2200 };
/* just to calculate coefficients for later use */
compute_resistor_weights(0, 255, -1.0,
3, resistances_gb, m_weights_g, 3600, 0,
3, resistances_gb, m_weights_b, 3600, 0,
2, resistances_r, m_weights_r, 3600, 0);
}
save_item(NAME(m_status));
save_pointer(NAME(m_ram), 0x800);
save_pointer(NAME(m_palram), 0x100);
save_item(NAME(m_param_offset_latch));
save_item(NAME(m_xpos));
save_item(NAME(m_ypos));
save_item(NAME(m_color1));
save_item(NAME(m_color2));
save_item(NAME(m_mode));
save_item(NAME(m_pix_xsize));
save_item(NAME(m_pix_ysize));
save_item(NAME(m_vregs));
save_item(NAME(m_bk_color));
save_item(NAME(m_vbank));
save_item(NAME(m_weights_r));
save_item(NAME(m_weights_g));
save_item(NAME(m_weights_b));
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void mb_vcu_device::device_reset()
{
m_status = 1;
for(int i=0;i<0x80000;i++)
{
write_byte(i,0x0f);
}
}
//**************************************************************************
// READ/WRITE HANDLERS
//**************************************************************************
// uint8_t *pcg = memregion("sub2")->base();
READ8_MEMBER( mb_vcu_device::read_ram )
{
return m_ram[offset];
}
WRITE8_MEMBER( mb_vcu_device::write_ram )
{
m_ram[offset] = data;
}
WRITE8_MEMBER( mb_vcu_device::write_vregs )
{
m_vregs[offset] = data;
}
/* latches RAM offset to send to params */
READ8_MEMBER( mb_vcu_device::load_params )
{
m_param_offset_latch = offset;
m_xpos = m_ram[m_param_offset_latch + 1] | (m_ram[m_param_offset_latch + 2]<<8);
m_ypos = m_ram[m_param_offset_latch + 3] | (m_ram[m_param_offset_latch + 4]<<8);
m_color1 = m_ram[m_param_offset_latch + 5];
m_color2 = m_ram[m_param_offset_latch + 6];
m_mode = m_ram[m_param_offset_latch + 7];
m_pix_xsize = m_ram[m_param_offset_latch + 8] + 1;
m_pix_ysize = m_ram[m_param_offset_latch + 9] + 1;
if(0)
{
printf("[0] %02x ",m_ram[m_param_offset_latch]);
printf("X: %04x ",m_xpos);
printf("Y: %04x ",m_ypos);
printf("C1:%02x ",m_color1);
printf("C2:%02x ",m_color2);
printf("M :%02x ",m_mode);
printf("XS:%02x ",m_pix_xsize);
printf("YS:%02x ",m_pix_ysize);
printf("\n");
}
return 0; // open bus?
}
READ8_MEMBER( mb_vcu_device::load_gfx )
{
int xi,yi;
int dstx,dsty;
uint8_t dot;
int bits = 0;
uint8_t pen = 0;
uint8_t cur_layer;
uint8_t opaque_pen;
// printf("%02x %02x\n",m_mode >> 2,m_mode & 3);
// cur_layer = (m_mode & 0x3);
cur_layer = (m_mode & 2) >> 1;
opaque_pen = (cur_layer == 1);
switch(m_mode >> 2)
{
case 0x00: // 4bpp
for(yi=0;yi<m_pix_ysize;yi++)
{
for(xi=0;xi<m_pix_xsize;xi++)
{
dstx = (m_xpos + xi);
dsty = (m_ypos + yi);
if(dstx >= 0 && dsty >= 0 && dstx < 256 && dsty < 256)
{
dot = m_cpu->space(AS_PROGRAM).read_byte(((offset + (bits >> 3)) & 0x1fff) + 0x4000) >> (4-(bits & 7));
dot&= 0xf;
if(dot != 0xf || opaque_pen)
write_byte(dstx|dsty<<8|cur_layer<<16|m_vbank<<18, dot);
}
bits += 4;
}
}
break;
case 0x02: // 1bpp
for(yi=0;yi<m_pix_ysize;yi++)
{
for(xi=0;xi<m_pix_xsize;xi++)
{
dstx = (m_xpos + xi);
dsty = (m_ypos + yi);
if(dstx >= 0 && dsty >= 0 && dstx < 256 && dsty < 256)
{
dot = m_cpu->space(AS_PROGRAM).read_byte(((offset + (bits >> 3)) & 0x1fff) + 0x4000) >> (7-(bits & 7));
dot&= 1;
pen = dot ? (m_color1 >> 4) : (m_color1 & 0xf);
if(pen != 0xf || opaque_pen)
write_byte(dstx|dsty<<8|cur_layer<<16|m_vbank<<18, pen);
}
bits++;
}
}
break;
case 0x03: //2bpp
for (yi = 0; yi < m_pix_ysize; yi++)
{
for (xi = 0; xi < m_pix_xsize; xi++)
{
dstx = (m_xpos + xi);
dsty = (m_ypos + yi);
if(dstx >= 0 && dsty >= 0 && dstx < 256 && dsty < 256)
{
dot = m_cpu->space(AS_PROGRAM).read_byte(((offset + (bits >> 3)) & 0x1fff) + 0x4000) >> (6-(bits & 7));
switch(dot & 3)
{
case 0:
pen = m_color1 & 0xf;
break;
case 1:
pen = m_color1 >> 4;
break;
case 2:
pen = m_color2 & 0xf;
break;
case 3:
pen = m_color2 >> 4;
break;
}
if(pen != 0xf || opaque_pen)
write_byte(dstx|dsty<<8|cur_layer<<16|m_vbank<<18, pen);
}
bits+=2;
}
}
break;
default:
popmessage("Unsupported draw mode");
break;
}
return 0; // open bus?
}
/*
Read-Modify-Write operations
---0 -111 (0x07) write to i/o
---0 -011 (0x03) clear VRAM
---1 -011 (0x13) collision detection
*/
READ8_MEMBER( mb_vcu_device::load_set_clr )
{
int xi,yi;
int dstx,dsty;
// uint8_t dot;
switch(m_mode)
{
case 0x13:
{
//int16_t srcx = m_ram[m_param_offset_latch + 1];
//int16_t srcy = m_ram[m_param_offset_latch + 3];
//uint16_t src_xsize = m_ram[m_param_offset_latch + 18] + 1;
//uint16_t src_ysize = m_ram[m_param_offset_latch + 19] + 1;
int collision_flag = 0;
for (yi = 0; yi < m_pix_ysize; yi++)
{
for (xi = 0; xi < m_pix_xsize; xi++)
{
dstx = (m_xpos + xi);
dsty = (m_ypos + yi);
if(dstx < 256 && dsty < 256)
{
uint8_t res = read_byte(dstx|dsty<<8|0<<16|(m_vbank)<<18);
//uint8_t res2 = read_byte(srcx|srcy<<8|0<<16|(m_vbank)<<18);
//printf("%02x %02x\n",res,res2);
// TODO: how it calculates the pen? Might use the commented out stuff and/or the offset somehow
if(res == 5)
{
collision_flag++;
// test++;
}
}
//srcx++;
}
//srcy++;
}
// threshold for collision, necessary to avoid bogus collision hits
// the typical test scenario is to shoot near the top left hatch for stage 1 then keep shooting,
// at some point the top right hatch will bogusly detect a collision without this.
// It's also unlikely that game tests 1x1 targets anyway, as the faster moving targets are quite too easy to hit that way.
// TODO: likely it works differently (checks area?)
if(collision_flag > 5)
m_ram[m_param_offset_latch] |= 8;
else
m_ram[m_param_offset_latch] &= ~8;
break;
}
case 0x03:
{
for (yi = 0; yi < m_pix_ysize; yi++)
{
for (xi = 0; xi < m_pix_xsize; xi++)
{
dstx = (m_xpos + xi);
dsty = (m_ypos + yi);
if(dstx < 256 && dsty < 256)
write_byte(dstx|dsty<<8|0<<16|(m_vbank)<<18, 0xf);
}
}
break;
}
case 0x07:
for(int i=0;i<m_pix_xsize;i++)
write_io(i+(m_ypos<<8),m_ram[offset + i]);
break;
}
return 0; // open bus?
}
WRITE8_MEMBER( mb_vcu_device::background_color_w )
{
int bit0,bit1,bit2;
int r,g,b;
m_bk_color = data;
/* red component */
bit1 = (m_bk_color >> 7) & 0x01;
bit0 = (m_bk_color >> 6) & 0x01;
r = combine_weights(m_weights_r, bit0, bit1);
/* green component */
bit2 = (m_bk_color >> 5) & 0x01;
bit1 = (m_bk_color >> 4) & 0x01;
bit0 = (m_bk_color >> 3) & 0x01;
g = combine_weights(m_weights_g, bit0, bit1, bit2);
/* blue component */
bit2 = (m_bk_color >> 2) & 0x01;
bit1 = (m_bk_color >> 1) & 0x01;
bit0 = (m_bk_color >> 0) & 0x01;
b = combine_weights(m_weights_b, bit0, bit1, bit2);
m_palette->set_pen_color(0x100, rgb_t(r, g, b));
}
READ8_MEMBER( mb_vcu_device::status_r )
{
/*
---- ---x busy or vblank flag
*/
return m_status;
}
WRITE8_MEMBER( mb_vcu_device::vbank_w )
{
m_vbank = (data & 0x40) >> 6;
}
WRITE8_MEMBER( mb_vcu_device::vbank_clear_w )
{
m_vbank = (data & 0x40) >> 6;
// setting vbank clears VRAM in the setted bank, applies to Great Guns only since it never ever access the RMW stuff
for(int i=0;i<0x10000;i++)
{
write_byte(i|0x00000|m_vbank<<18,0x0f);
write_byte(i|0x10000|m_vbank<<18,0x0f);
}
}
//-------------------------------------------------
// update_screen -
//-------------------------------------------------
uint32_t mb_vcu_device::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
{
int x,y;
uint8_t dot;
bitmap.fill(m_palette->pen(0x100),cliprect);
for(y=0;y<256;y++)
{
for(x=0;x<256;x++)
{
dot = read_byte((x >> 0)|(y<<8)|1<<16|(m_vbank ^ 1)<<18);
//if(dot != 0xf)
{
dot|= m_vregs[1] << 4;
bitmap.pix32(y,x) = m_palette->pen(dot);
}
}
}
for(y=0;y<256;y++)
{
for(x=0;x<256;x++)
{
dot = read_byte((x >> 0)|(y<<8)|0<<16|(m_vbank ^ 1)<<18);
if(dot != 0xf)
{
dot|= m_vregs[1] << 4;
bitmap.pix32(y,x) = m_palette->pen(dot);
}
}
}
return 0;
}
void mb_vcu_device::screen_eof(void)
{
#if 0
for(int i=0;i<0x10000;i++)
{
write_byte(i|0x00000|m_vbank<<18,0x0f);
//write_byte(i|0x10000|m_vbank<<18,0x0f);
//write_byte(i|0x30000|m_vbank<<18,0x0f);
}
#endif
}