[picodrive.git] / pico / mode4.c

/*
 * mode4/SMS renderer
 * (C) notaz, 2009-2010
 *
 * This work is licensed under the terms of MAME license.
 * See COPYING file in the top-level directory.
 */
/*
 * TODO:
 * - TMS9918 modes?
 * - gg mode?
 * - column scroll (reg 0 bit7)
 * - 224/240 line modes
 * - doubled sprites
 */
#include "pico_int.h"

static void (*FinalizeLineM4)(int line);
static int skip_next_line;
static int screen_offset;

#define PLANAR_PIXEL(x,p) \
  t = pack & (0x80808080 >> p); \
  if (t) { \
    t = ((t >> (7-p)) | (t >> (14-p)) | (t >> (21-p)) | (t >> (28-p))) & 0x0f; \
    pd[x] = pal|t; \
  }

static int TileNormM4(int sx, int addr, int pal)
{
  unsigned char *pd = Pico.est.HighCol + sx;
  unsigned int pack, t;

  pack = *(unsigned int *)(PicoMem.vram + addr); /* Get 4 bitplanes / 8 pixels */
  if (pack)
  {
    PLANAR_PIXEL(0, 0)
    PLANAR_PIXEL(1, 1)
    PLANAR_PIXEL(2, 2)
    PLANAR_PIXEL(3, 3)
    PLANAR_PIXEL(4, 4)
    PLANAR_PIXEL(5, 5)
    PLANAR_PIXEL(6, 6)
    PLANAR_PIXEL(7, 7)
    return 0;
  }

  return 1; /* Tile blank */
}

static int TileFlipM4(int sx,int addr,int pal)
{
  unsigned char *pd = Pico.est.HighCol + sx;
  unsigned int pack, t;

  pack = *(unsigned int *)(PicoMem.vram + addr); /* Get 4 bitplanes / 8 pixels */
  if (pack)
  {
    PLANAR_PIXEL(0, 7)
    PLANAR_PIXEL(1, 6)
    PLANAR_PIXEL(2, 5)
    PLANAR_PIXEL(3, 4)
    PLANAR_PIXEL(4, 3)
    PLANAR_PIXEL(5, 2)
    PLANAR_PIXEL(6, 1)
    PLANAR_PIXEL(7, 0)
    return 0;
  }

  return 1; /* Tile blank */
}

static void draw_sprites(int scanline)
{
  struct PicoVideo *pv = &Pico.video;
  unsigned int sprites_addr[8];
  unsigned int sprites_x[8];
  unsigned char *sat;
  int xoff = 8; // relative to HighCol, which is (screen - 8)
  int sprite_base, addr_mask;
  int i, s, h;

  if (pv->reg[0] & 8)
    xoff = 0;

  sat = (unsigned char *)PicoMem.vram + ((pv->reg[5] & 0x7e) << 7);
  if (pv->reg[1] & 2) {
    addr_mask = 0xfe; h = 16;
  } else {
    addr_mask = 0xff; h = 8;
  }
  sprite_base = (pv->reg[6] & 4) << (13-2-1);

  for (i = s = 0; i < 64; i++)
  {
    int y;
    y = sat[i] + 1;
    if (y == 0xd1)
      break;
    if (y + h <= scanline || scanline < y)
      continue; // not on this line
    if (s >= 8) {
      pv->status |= SR_SOVR;
      break;
    }

    sprites_x[s] = xoff + sat[0x80 + i*2];
    sprites_addr[s] = sprite_base + ((sat[0x80 + i*2 + 1] & addr_mask) << (5-1)) +
      ((scanline - y) << (2-1));
    s++;
  }

  // really half-assed but better than nothing
  if (s > 1)
    pv->status |= SR_C;

  // now draw all sprites backwards
  for (--s; s >= 0; s--)
    TileNormM4(sprites_x[s], sprites_addr[s], 0x10);
}

// tilex_ty_prio merged to reduce register pressure
static void draw_strip(const unsigned short *nametab, int dx, int cells, int tilex_ty_prio)
{
  int oldcode = -1, blank = -1; // The tile we know is blank
  int addr = 0, pal = 0;

  // Draw tiles across screen:
  for (; cells > 0; dx += 8, tilex_ty_prio++, cells--)
  {
    int code, zero;

    code = nametab[tilex_ty_prio & 0x1f];
    if (code == blank)
      continue;
    if ((code ^ tilex_ty_prio) & 0x1000) // priority differs?
      continue;

    if (code != oldcode) {
      oldcode = code;
      // Get tile address/2:
      addr = (code & 0x1ff) << 4;
      addr += tilex_ty_prio >> 16;
      if (code & 0x0400)
        addr ^= 0xe; // Y-flip

      pal = (code>>7) & 0x10;
    }

    if (code&0x0200) zero = TileFlipM4(dx, addr, pal);
    else             zero = TileNormM4(dx, addr, pal);

    if (zero)
      blank = code; // We know this tile is blank now
  }
}

static void DrawDisplayM4(int scanline)
{
  struct PicoVideo *pv = &Pico.video;
  unsigned short *nametab;
  int line, tilex, dx, ty, cells;
  int cellskip = 0; // XXX
  int maxcells = 32;

  // Find the line in the name table
  line = pv->reg[9] + scanline; // vscroll + scanline
  if (line >= 224)
    line -= 224;

  // Find name table:
  nametab = PicoMem.vram;
  nametab += (pv->reg[2] & 0x0e) << (10-1);
  nametab += (line>>3) << (6-1);

  dx = pv->reg[8]; // hscroll
  if (scanline < 16 && (pv->reg[0] & 0x40))
    dx = 0; // hscroll disabled for top 2 rows

  tilex = ((-dx >> 3) + cellskip) & 0x1f;
  ty = (line & 7) << 1; // Y-Offset into tile
  cells = maxcells - cellskip;

  dx = ((dx - 1) & 7) + 1;
  if (dx != 8)
    cells++; // have hscroll, need to draw 1 cell more
  dx += cellskip << 3;

  // low priority tiles
  if (!(pv->debug_p & PVD_KILL_B))
    draw_strip(nametab, dx, cells, tilex | 0x0000 | (ty << 16));

  // sprites
  if (!(pv->debug_p & PVD_KILL_S_LO))
    draw_sprites(scanline);

  // high priority tiles (use virtual layer switch just for fun)
  if (!(pv->debug_p & PVD_KILL_A))
    draw_strip(nametab, dx, cells, tilex | 0x1000 | (ty << 16));

  if (pv->reg[0] & 0x20)
    // first column masked
    ((int *)Pico.est.HighCol)[2] = ((int *)Pico.est.HighCol)[3] = 0xe0e0e0e0;
}

void PicoFrameStartMode4(void)
{
  int lines = 192;
  skip_next_line = 0;
  screen_offset = 24;
  Pico.est.rendstatus = PDRAW_32_COLS;

  if ((Pico.video.reg[0] & 6) == 6 && (Pico.video.reg[1] & 0x18)) {
    if (Pico.video.reg[1] & 0x08) {
      screen_offset = 0;
      lines = 240;
    }
    else {
      screen_offset = 8;
      lines = 224;
    }
  }

  if (Pico.est.rendstatus != rendstatus_old || lines != rendlines) {
    emu_video_mode_change(screen_offset, lines, 1);
    rendstatus_old = Pico.est.rendstatus;
    rendlines = lines;
  }

  Pico.est.DrawLineDest = (char *)DrawLineDestBase + screen_offset * DrawLineDestIncrement;
}

void PicoLineMode4(int line)
{
  if (skip_next_line > 0) {
    skip_next_line--;
    return;
  }

  if (PicoScanBegin != NULL)
    skip_next_line = PicoScanBegin(line + screen_offset);

  // Draw screen:
  BackFill(Pico.video.reg[7] & 0x0f, 0, &Pico.est);
  if (Pico.video.reg[1] & 0x40)
    DrawDisplayM4(line);

  if (FinalizeLineM4 != NULL)
    FinalizeLineM4(line);

  if (PicoScanEnd != NULL)
    skip_next_line = PicoScanEnd(line + screen_offset);

  Pico.est.DrawLineDest = (char *)Pico.est.DrawLineDest + DrawLineDestIncrement;
}

void PicoDoHighPal555M4(void)
{
  unsigned int *spal=(void *)PicoMem.cram;
  unsigned int *dpal=(void *)Pico.est.HighPal;
  unsigned int t;
  int i;

  Pico.m.dirtyPal = 0;

  /* cram is always stored as shorts, even though real hardware probably uses bytes */
  for (i = 0x20/2; i > 0; i--, spal++, dpal++) {
    t = *spal;
#ifdef USE_BGR555
    t = ((t & 0x00030003)<< 3) | ((t & 0x000c000c)<<7) | ((t & 0x00300030)<<10);
#else
    t = ((t & 0x00030003)<<14) | ((t & 0x000c000c)<<7) | ((t & 0x00300030)>>1);
#endif
    t |= t >> 2;
    t |= (t >> 4) & 0x08610861;
    *dpal = t;
  }
  Pico.est.HighPal[0xe0] = 0;
}

static void FinalizeLineRGB555M4(int line)
{
  if (Pico.m.dirtyPal)
    PicoDoHighPal555M4();

  // standard FinalizeLine can finish it for us,
  // with features like scaling and such
  FinalizeLine555(0, line, &Pico.est);
}

static void FinalizeLine8bitM4(int line)
{
  unsigned char *pd = Pico.est.DrawLineDest;

  if (!(PicoOpt & POPT_DIS_32C_BORDER))
    pd += 32;

  memcpy(pd, Pico.est.HighCol + 8, 256);
}

void PicoDrawSetOutputMode4(pdso_t which)
{
  switch (which)
  {
    case PDF_8BIT:   FinalizeLineM4 = FinalizeLine8bitM4; break;
    case PDF_RGB555: FinalizeLineM4 = FinalizeLineRGB555M4; break;
    default:         FinalizeLineM4 = NULL; break;
  }
}

// vim:shiftwidth=2:ts=2:expandtab
Commit	Line	Data
	1	/*
	2	* mode4/SMS renderer
	3	* (C) notaz, 2009-2010
	4	*
	5	* This work is licensed under the terms of MAME license.
	6	* See COPYING file in the top-level directory.
	7	*/
	8	/*
	9	* TODO:
	10	* - TMS9918 modes?
	11	* - gg mode?
	12	* - column scroll (reg 0 bit7)
	13	* - 224/240 line modes
	14	* - doubled sprites
	15	*/
	16	#include "pico_int.h"
	17
	18	static void (*FinalizeLineM4)(int line);
	19	static int skip_next_line;
	20	static int screen_offset;
	21
	22	#define PLANAR_PIXEL(x,p) \
	23	t = pack & (0x80808080 >> p); \
	24	if (t) { \
	25	t = ((t >> (7-p)) \| (t >> (14-p)) \| (t >> (21-p)) \| (t >> (28-p))) & 0x0f; \
	26	pd[x] = pal\|t; \
	27	}
	28
	29	static int TileNormM4(int sx, int addr, int pal)
	30	{
	31	unsigned char *pd = Pico.est.HighCol + sx;
	32	unsigned int pack, t;
	33
	34	pack = (unsigned int )(PicoMem.vram + addr); /* Get 4 bitplanes / 8 pixels */
	35	if (pack)
	36	{
	37	PLANAR_PIXEL(0, 0)
	38	PLANAR_PIXEL(1, 1)
	39	PLANAR_PIXEL(2, 2)
	40	PLANAR_PIXEL(3, 3)
	41	PLANAR_PIXEL(4, 4)
	42	PLANAR_PIXEL(5, 5)
	43	PLANAR_PIXEL(6, 6)
	44	PLANAR_PIXEL(7, 7)
	45	return 0;
	46	}
	47
	48	return 1; /* Tile blank */
	49	}
	50
	51	static int TileFlipM4(int sx,int addr,int pal)
	52	{
	53	unsigned char *pd = Pico.est.HighCol + sx;
	54	unsigned int pack, t;
	55
	56	pack = (unsigned int )(PicoMem.vram + addr); /* Get 4 bitplanes / 8 pixels */
	57	if (pack)
	58	{
	59	PLANAR_PIXEL(0, 7)
	60	PLANAR_PIXEL(1, 6)
	61	PLANAR_PIXEL(2, 5)
	62	PLANAR_PIXEL(3, 4)
	63	PLANAR_PIXEL(4, 3)
	64	PLANAR_PIXEL(5, 2)
	65	PLANAR_PIXEL(6, 1)
	66	PLANAR_PIXEL(7, 0)
	67	return 0;
	68	}
	69
	70	return 1; /* Tile blank */
	71	}
	72
	73	static void draw_sprites(int scanline)
	74	{
	75	struct PicoVideo *pv = &Pico.video;
	76	unsigned int sprites_addr[8];
	77	unsigned int sprites_x[8];
	78	unsigned char *sat;
	79	int xoff = 8; // relative to HighCol, which is (screen - 8)
	80	int sprite_base, addr_mask;
	81	int i, s, h;
	82
	83	if (pv->reg[0] & 8)
	84	xoff = 0;
	85
	86	sat = (unsigned char *)PicoMem.vram + ((pv->reg[5] & 0x7e) << 7);
	87	if (pv->reg[1] & 2) {
	88	addr_mask = 0xfe; h = 16;
	89	} else {
	90	addr_mask = 0xff; h = 8;
	91	}
	92	sprite_base = (pv->reg[6] & 4) << (13-2-1);
	93
	94	for (i = s = 0; i < 64; i++)
	95	{
	96	int y;
	97	y = sat[i] + 1;
	98	if (y == 0xd1)
	99	break;
	100	if (y + h <= scanline \|\| scanline < y)
	101	continue; // not on this line
	102	if (s >= 8) {
	103	pv->status \|= SR_SOVR;
	104	break;
	105	}
	106
	107	sprites_x[s] = xoff + sat[0x80 + i*2];
	108	sprites_addr[s] = sprite_base + ((sat[0x80 + i*2 + 1] & addr_mask) << (5-1)) +
	109	((scanline - y) << (2-1));
	110	s++;
	111	}
	112
	113	// really half-assed but better than nothing
	114	if (s > 1)
	115	pv->status \|= SR_C;
	116
	117	// now draw all sprites backwards
	118	for (--s; s >= 0; s--)
	119	TileNormM4(sprites_x[s], sprites_addr[s], 0x10);
	120	}
	121
	122	// tilex_ty_prio merged to reduce register pressure
	123	static void draw_strip(const unsigned short *nametab, int dx, int cells, int tilex_ty_prio)
	124	{
	125	int oldcode = -1, blank = -1; // The tile we know is blank
	126	int addr = 0, pal = 0;
	127
	128	// Draw tiles across screen:
	129	for (; cells > 0; dx += 8, tilex_ty_prio++, cells--)
	130	{
	131	int code, zero;
	132
	133	code = nametab[tilex_ty_prio & 0x1f];
	134	if (code == blank)
	135	continue;
	136	if ((code ^ tilex_ty_prio) & 0x1000) // priority differs?
	137	continue;
	138
	139	if (code != oldcode) {
	140	oldcode = code;
	141	// Get tile address/2:
	142	addr = (code & 0x1ff) << 4;
	143	addr += tilex_ty_prio >> 16;
	144	if (code & 0x0400)
	145	addr ^= 0xe; // Y-flip
	146
	147	pal = (code>>7) & 0x10;
	148	}
	149
	150	if (code&0x0200) zero = TileFlipM4(dx, addr, pal);
	151	else zero = TileNormM4(dx, addr, pal);
	152
	153	if (zero)
	154	blank = code; // We know this tile is blank now
	155	}
	156	}
	157
	158	static void DrawDisplayM4(int scanline)
	159	{
	160	struct PicoVideo *pv = &Pico.video;
	161	unsigned short *nametab;
	162	int line, tilex, dx, ty, cells;
	163	int cellskip = 0; // XXX
	164	int maxcells = 32;
	165
	166	// Find the line in the name table
	167	line = pv->reg[9] + scanline; // vscroll + scanline
	168	if (line >= 224)
	169	line -= 224;
	170
	171	// Find name table:
	172	nametab = PicoMem.vram;
	173	nametab += (pv->reg[2] & 0x0e) << (10-1);
	174	nametab += (line>>3) << (6-1);
	175
	176	dx = pv->reg[8]; // hscroll
	177	if (scanline < 16 && (pv->reg[0] & 0x40))
	178	dx = 0; // hscroll disabled for top 2 rows
	179
	180	tilex = ((-dx >> 3) + cellskip) & 0x1f;
	181	ty = (line & 7) << 1; // Y-Offset into tile
	182	cells = maxcells - cellskip;
	183
	184	dx = ((dx - 1) & 7) + 1;
	185	if (dx != 8)
	186	cells++; // have hscroll, need to draw 1 cell more
	187	dx += cellskip << 3;
	188
	189	// low priority tiles
	190	if (!(pv->debug_p & PVD_KILL_B))
	191	draw_strip(nametab, dx, cells, tilex \| 0x0000 \| (ty << 16));
	192
	193	// sprites
	194	if (!(pv->debug_p & PVD_KILL_S_LO))
	195	draw_sprites(scanline);
	196
	197	// high priority tiles (use virtual layer switch just for fun)
	198	if (!(pv->debug_p & PVD_KILL_A))
	199	draw_strip(nametab, dx, cells, tilex \| 0x1000 \| (ty << 16));
	200
	201	if (pv->reg[0] & 0x20)
	202	// first column masked
	203	((int )Pico.est.HighCol)[2] = ((int )Pico.est.HighCol)[3] = 0xe0e0e0e0;
	204	}
	205
	206	void PicoFrameStartMode4(void)
	207	{
	208	int lines = 192;
	209	skip_next_line = 0;
	210	screen_offset = 24;
	211	Pico.est.rendstatus = PDRAW_32_COLS;
	212
	213	if ((Pico.video.reg[0] & 6) == 6 && (Pico.video.reg[1] & 0x18)) {
	214	if (Pico.video.reg[1] & 0x08) {
	215	screen_offset = 0;
	216	lines = 240;
	217	}
	218	else {
	219	screen_offset = 8;
	220	lines = 224;
	221	}
	222	}
	223
	224	if (Pico.est.rendstatus != rendstatus_old \|\| lines != rendlines) {
	225	emu_video_mode_change(screen_offset, lines, 1);
	226	rendstatus_old = Pico.est.rendstatus;
	227	rendlines = lines;
	228	}
	229
	230	Pico.est.DrawLineDest = (char )DrawLineDestBase + screen_offset DrawLineDestIncrement;
	231	}
	232
	233	void PicoLineMode4(int line)
	234	{
	235	if (skip_next_line > 0) {
	236	skip_next_line--;
	237	return;
	238	}
	239
	240	if (PicoScanBegin != NULL)
	241	skip_next_line = PicoScanBegin(line + screen_offset);
	242
	243	// Draw screen:
	244	BackFill(Pico.video.reg[7] & 0x0f, 0, &Pico.est);
	245	if (Pico.video.reg[1] & 0x40)
	246	DrawDisplayM4(line);
	247
	248	if (FinalizeLineM4 != NULL)
	249	FinalizeLineM4(line);
	250
	251	if (PicoScanEnd != NULL)
	252	skip_next_line = PicoScanEnd(line + screen_offset);
	253
	254	Pico.est.DrawLineDest = (char *)Pico.est.DrawLineDest + DrawLineDestIncrement;
	255	}
	256
	257	void PicoDoHighPal555M4(void)
	258	{
	259	unsigned int spal=(void )PicoMem.cram;
	260	unsigned int dpal=(void )Pico.est.HighPal;
	261	unsigned int t;
	262	int i;
	263
	264	Pico.m.dirtyPal = 0;
	265
	266	/* cram is always stored as shorts, even though real hardware probably uses bytes */
	267	for (i = 0x20/2; i > 0; i--, spal++, dpal++) {
	268	t = *spal;
	269	#ifdef USE_BGR555
	270	t = ((t & 0x00030003)<< 3) \| ((t & 0x000c000c)<<7) \| ((t & 0x00300030)<<10);
	271	#else
	272	t = ((t & 0x00030003)<<14) \| ((t & 0x000c000c)<<7) \| ((t & 0x00300030)>>1);
	273	#endif
	274	t \|= t >> 2;
	275	t \|= (t >> 4) & 0x08610861;
	276	*dpal = t;
	277	}
	278	Pico.est.HighPal[0xe0] = 0;
	279	}
	280
	281	static void FinalizeLineRGB555M4(int line)
	282	{
	283	if (Pico.m.dirtyPal)
	284	PicoDoHighPal555M4();
	285
	286	// standard FinalizeLine can finish it for us,
	287	// with features like scaling and such
	288	FinalizeLine555(0, line, &Pico.est);
	289	}
	290
	291	static void FinalizeLine8bitM4(int line)
	292	{
	293	unsigned char *pd = Pico.est.DrawLineDest;
	294
	295	if (!(PicoOpt & POPT_DIS_32C_BORDER))
	296	pd += 32;
	297
	298	memcpy(pd, Pico.est.HighCol + 8, 256);
	299	}
	300
	301	void PicoDrawSetOutputMode4(pdso_t which)
	302	{
	303	switch (which)
	304	{
	305	case PDF_8BIT: FinalizeLineM4 = FinalizeLine8bitM4; break;
	306	case PDF_RGB555: FinalizeLineM4 = FinalizeLineRGB555M4; break;
	307	default: FinalizeLineM4 = NULL; break;
	308	}
	309	}
	310
	311	// vim:shiftwidth=2:ts=2:expandtab