[picodrive.git] / pico / cd / gfx.c

/***************************************************************************************
 *  Genesis Plus
 *  CD graphics processor
 *
 *  Copyright (C) 2012  Eke-Eke (Genesis Plus GX)
 *
 *  Redistribution and use of this code or any derivative works are permitted
 *  provided that the following conditions are met:
 *
 *   - Redistributions may not be sold, nor may they be used in a commercial
 *     product or activity.
 *
 *   - Redistributions that are modified from the original source must include the
 *     complete source code, including the source code for all components used by a
 *     binary built from the modified sources. However, as a special exception, the
 *     source code distributed need not include anything that is normally distributed
 *     (in either source or binary form) with the major components (compiler, kernel,
 *     and so on) of the operating system on which the executable runs, unless that
 *     component itself accompanies the executable.
 *
 *   - Redistributions must reproduce the above copyright notice, this list of
 *     conditions and the following disclaimer in the documentation and/or other
 *     materials provided with the distribution.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************************/
#include "../pico_int.h"
#include "genplus_macros.h"

typedef struct
{
  //uint32 cycles;                    /* current cycles count for graphics operation */
  //uint32 cyclesPerLine;             /* current graphics operation timings */
  uint32 dotMask;                   /* stamp map size mask */
  uint32 stampMask;                 /* stamp number mask */
  uint16 *tracePtr;                 /* trace vector pointer */
  uint16 *mapPtr;                   /* stamp map table base address */
  uint8 stampShift;                 /* stamp pixel shift value (related to stamp size) */
  uint8 mapShift;                   /* stamp map table shift value (related to stamp map size) */
  uint16 bufferOffset;              /* image buffer column offset */
  uint32 bufferStart;               /* image buffer start index */
  uint32 y_step;                    /* pico: render line step */
  uint8 lut_prio[4][0x10][0x10];    /* WORD-RAM data writes priority lookup table */
  uint8 lut_pixel[0x200];           /* Graphics operation dot offset lookup table */
  uint16 lut_cell2[0x80];           /* Graphics operation stamp offset lookup table */
  uint16 lut_cell4[0x80];           /* Graphics operation stamp offset lookup table */
} gfx_t;

static gfx_t gfx;

static void gfx_schedule(void);

/***************************************************************/
/*      Rotation / Scaling operation (2M Mode)                 */
/***************************************************************/

void gfx_init(void)
{
  int i, j;
  uint8 row, col, temp;

  memset(&gfx, 0, sizeof(gfx));

  /* Initialize priority modes lookup table */
  for (i = 0; i < 0x10; i++)
  {
    for (j = 0; j < 0x10; j++)
    {
      /* normal */
      gfx.lut_prio[0][i][j] = j;
      /* underwrite */
      gfx.lut_prio[1][i][j] = i ? i : j;
      /* overwrite */
      gfx.lut_prio[2][i][j] = j ? j : i;
      /* invalid */
      gfx.lut_prio[3][i][j] = i;
    }
  }

  /* Initialize cell lookup table             */
  /* table entry = yyxxhrr (7 bits)           */
  /* with: yy = cell row (0-3)                */
  /*       xx = cell column (0-3)             */
  /*      hrr = HFLIP & ROTATION bits         */
  for (i=0; i<0x80; i++)
  {
    /* one stamp = 2x2 cells (16x16) or 4x4 cells (32x32) */
    row = (i >> 5) & 3;
    col = (i >> 3) & 3;

    if (i & 4) { col = col ^ 3; }  /* HFLIP (always first)  */ 
    if (i & 2) { col = col ^ 3; row = row ^ 3; }  /* ROLL1 */
    if (i & 1) { temp = col; col = row ^ 3; row = temp; }  /* ROLL0  */

    /* cell offset (0-3 or 0-15) */
    gfx.lut_cell2[i] = ((row&1) + (col&1) * 2) << 6;
    gfx.lut_cell4[i] = ((row&3) + (col&3) * 4) << 6;
  }

  /* Initialize pixel lookup table      */
  /* table entry = yyyxxxhrr (9 bits)   */
  /* with:  yyy = pixel row  (0-7)      */
  /*        xxx = pixel column (0-7)    */
  /*        hrr = HFLIP & ROTATION bits */
  for (i=0; i<0x200; i++)
  {
    /* one cell = 8x8 pixels */
    row = (i >> 6) & 7;
    col = (i >> 3) & 7;

    if (i & 4) { col = col ^ 7; }   /* HFLIP (always first) */ 
    if (i & 2) { col = col ^ 7; row = row ^ 7; }  /* ROLL1 */
    if (i & 1) { temp = col; col = row ^ 7; row = temp; } /* ROLL0 */

    /* pixel offset (0-63) */
    gfx.lut_pixel[i] = col + row * 8;
  }
}

int gfx_context_save(uint8 *state)
{
  uint32 tmp32;
  int bufferptr = 0;

  //save_param(&gfx.cycles, sizeof(gfx.cycles));
  //save_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine));
  save_param(&gfx.dotMask, sizeof(gfx.dotMask));
  save_param(&gfx.stampShift, sizeof(gfx.stampShift));
  save_param(&gfx.mapShift, sizeof(gfx.mapShift));
  save_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset));
  save_param(&gfx.bufferStart, sizeof(gfx.bufferStart));

  tmp32 = (uint8 *)(gfx.tracePtr) - Pico_mcd->word_ram2M;
  save_param(&tmp32, 4);

  tmp32 = (uint8 *)(gfx.mapPtr) - Pico_mcd->word_ram2M;
  save_param(&tmp32, 4);

  save_param(&gfx.y_step, sizeof(gfx.y_step));

  return bufferptr;
}

int gfx_context_load(const uint8 *state)
{
  uint32 tmp32;
  int bufferptr = 0;

  //load_param(&gfx.cycles, sizeof(gfx.cycles));
  //load_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine));
  load_param(&gfx.dotMask, sizeof(gfx.dotMask));
  load_param(&gfx.stampShift, sizeof(gfx.stampShift));
  load_param(&gfx.mapShift, sizeof(gfx.mapShift));
  load_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset));
  load_param(&gfx.bufferStart, sizeof(gfx.bufferStart));

  load_param(&tmp32, 4);
  gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32);

  load_param(&tmp32, 4);
  gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32);

  load_param(&gfx.y_step, sizeof(gfx.y_step));

  return bufferptr;
}

static inline int gfx_pixel(uint32 xpos, uint32 ypos, uint16 *lut_cell)
{
  uint16 stamp_data;
  uint32 stamp_index;
  uint8 pixel_out = 0x00;

  /* check if pixel is outside stamp map */
  if (((xpos | ypos) & ~gfx.dotMask) == 0)
  {
    /* read stamp map table data */
    stamp_data = gfx.mapPtr[(xpos >> gfx.stampShift) | ((ypos >> gfx.stampShift) << gfx.mapShift)];

    /* stamp generator base index                                     */
    /* sss ssssssss ccyyyxxx (16x16) or sss sssssscc ccyyyxxx (32x32) */
    /* with:  s = stamp number (1 stamp = 16x16 or 32x32 pixels)      */
    /*        c = cell offset  (0-3 for 16x16, 0-15 for 32x32)        */
    /*      yyy = line offset  (0-7)                                  */
    /*      xxx = pixel offset (0-7)                                  */
    stamp_index = (stamp_data & gfx.stampMask) << 8;

    if (stamp_index)
    {
      /* extract HFLIP & ROTATION bits */
      stamp_data = (stamp_data >> 13) & 7;

      /* cell offset (0-3 or 0-15)                             */
      /* table entry = yyxxhrr (7 bits)                        */
      /* with: yy = cell row  (0-3) = (ypos >> (11 + 3)) & 3   */
      /*       xx = cell column (0-3) = (xpos >> (11 + 3)) & 3 */
      /*      hrr = HFLIP & ROTATION bits                      */
      stamp_index |= lut_cell[stamp_data | ((ypos >> 9) & 0x60) | ((xpos >> 11) & 0x18)];

      /* pixel  offset (0-63)                              */
      /* table entry = yyyxxxhrr (9 bits)                  */
      /* with: yyy = pixel row  (0-7) = (ypos >> 11) & 7   */
      /*       xxx = pixel column (0-7) = (xpos >> 11) & 7 */
      /*       hrr = HFLIP & ROTATION bits                 */
      stamp_index |= gfx.lut_pixel[stamp_data | ((ypos >> 5) & 0x1c0) | ((xpos >> 8) & 0x38)];

      /* read pixel pair (2 pixels/byte) */
      pixel_out = READ_BYTE(Pico_mcd->word_ram2M, stamp_index >> 1);

      /* extract left or right pixel */
      pixel_out >>= 4 * !(stamp_index & 1);
      pixel_out &= 0x0f;
    }
  }

  return pixel_out;
}

#define RENDER_LOOP(N, UPDP, COND1, COND2) do {				\
  if (bufferIndex & 1) {						\
    bufferIndex ^= 1;							\
    goto right##N; /* no initial left pixel */				\
  }									\
  /* process all dots */						\
  while (width--)							\
  {									\
    /* left pixel */							\
    xpos &= mask;							\
    ypos &= mask;							\
									\
    if (COND1) {							\
      pixel_out = gfx_pixel(xpos, ypos, lut_cell);			\
      UPDP;								\
    }									\
									\
    if (COND2) {							\
      /* read out paired pixel data */					\
      pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1);	\
									\
      /* priority mode write */						\
      pixel_in = (lut_prio[(pixel_in & 0xf0) >> 4][pixel_out] << 4) |	\
                 (pixel_in & 0x0f);					\
									\
      /* write data to image buffer */					\
      WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_in);	\
    }									\
									\
    /* increment pixel position */					\
    xpos += xoffset;							\
    ypos += yoffset;							\
									\
right##N:								\
    if (width-- == 0) break;						\
									\
    /* right pixel */							\
    xpos &= mask;							\
    ypos &= mask;							\
									\
    if (COND1) {							\
      pixel_out = gfx_pixel(xpos, ypos, lut_cell);			\
      UPDP;								\
    }									\
									\
    if (COND2) {							\
      /* read out paired pixel data */					\
      pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1);	\
									\
      /* priority mode write */						\
      pixel_in = (lut_prio[pixel_in & 0x0f][pixel_out]) |		\
                 (pixel_in & 0xf0);					\
									\
      /* write data to image buffer */					\
      WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_in);	\
    }									\
									\
    /* increment pixel position */					\
    xpos += xoffset;							\
    ypos += yoffset;							\
									\
    /* next pixel */							\
    bufferIndex += 2;							\
    /* check current pixel position  */					\
    if ((bufferIndex & 7) == 0)						\
    {									\
      /* next cell: increment buffer offset by one column (minus 8 pixels) */ \
      bufferIndex += gfx.bufferOffset-1;				\
    }									\
  }									\
} while (0)

static void gfx_render(uint32 bufferIndex, uint32 width)
{
  uint8 pixel_in, pixel_out;
  uint32 priority;
  uint8 (*lut_prio)[0x10];
  uint16 *lut_cell;
  uint32 mask;

  /* pixel map start position for current line (13.3 format converted to 13.11) */
  uint32 xpos = *gfx.tracePtr++ << 8;
  uint32 ypos = *gfx.tracePtr++ << 8;

  /* pixel map offset values for current line (5.11 format) */
  uint32 xoffset = (int16) *gfx.tracePtr++;
  uint32 yoffset = (int16) *gfx.tracePtr++;

  priority = (Pico_mcd->s68k_regs[2] << 8) | Pico_mcd->s68k_regs[3];
  priority = (priority >> 3) & 0x03;
  lut_prio = gfx.lut_prio[priority];

  lut_cell = (Pico_mcd->s68k_regs[0x58+1] & 0x02) ? gfx.lut_cell4 : gfx.lut_cell2;

  /* check if stamp map is repeated */
  mask = 0xffffff; /* 24-bit range */
  if (Pico_mcd->s68k_regs[0x58+1] & 0x01)
  {
    /* stamp map range */
    mask = gfx.dotMask;
  }

  pixel_out = 0;
  if (xoffset+(1U<<10) <= 1U<<11 && yoffset+(1U<<10) <= 1U<<11) {
    /* upscaling >= 2x, test for duplicate pixels to avoid recalculation */
    uint32 oldx, oldy;
    oldx = oldy = ~xpos;
    RENDER_LOOP(1, oldx = xpos;oldy = ypos, (oldx^xpos ^ oldy^ypos) >> 11, (!priority) | pixel_out);
  } else {
    RENDER_LOOP(3,                        , 1, (!priority) | pixel_out);
  }
}

void gfx_start(uint32 base)
{
  /* make sure 2M mode is enabled */
  if (!(Pico_mcd->s68k_regs[3] & 0x04))
  {
    uint32 mask = 0;
    uint32 reg;
    
    /* trace vector pointer */
    gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + ((base << 2) & 0x3fff8));

    /* stamps & stamp map size */
    switch ((Pico_mcd->s68k_regs[0x58+1] >> 1) & 0x03)
    {
      case 0:
        gfx.dotMask = 0x07ffff;   /* 256x256 dots/map  */
        gfx.stampMask = 0x7ff;    /* 16x16 dots/stamp  */
        gfx.stampShift = 11 + 4;  /* 16x16 dots/stamp  */
        gfx.mapShift = 4;         /* 16x16 stamps/map  */
        mask = 0x3fe00;           /* 512 bytes/table   */
        break;

      case 1:
        gfx.dotMask = 0x07ffff;   /* 256x256 dots/map  */
        gfx.stampMask = 0x7fc;    /* 16x16 dots/stamp  */
        gfx.stampShift = 11 + 5;  /* 32x32 dots/stamp  */
        gfx.mapShift = 3;         /* 8x8 stamps/map    */
        mask = 0x3ff80;           /* 128 bytes/table   */
        break;

      case 2:
        gfx.dotMask = 0x7fffff;   /* 4096*4096 dots/map */
        gfx.stampMask = 0x7ff;    /* 16x16 dots/stamp   */
        gfx.stampShift = 11 + 4;  /* 16x16 dots/stamp   */
        gfx.mapShift = 8;         /* 256x256 stamps/map */
        mask = 0x20000;           /* 131072 bytes/table */
        break;

      case 3:
        gfx.dotMask = 0x7fffff;   /* 4096*4096 dots/map */
        gfx.stampMask = 0x7fc;    /* 16x16 dots/stamp   */
        gfx.stampShift = 11 + 5;  /* 32x32 dots/stamp   */
        gfx.mapShift = 7;         /* 128x128 stamps/map */
        mask = 0x38000;           /* 32768 bytes/table  */
        break;
    }

    /* stamp map table base address */
    reg = (Pico_mcd->s68k_regs[0x5a] << 8) | Pico_mcd->s68k_regs[0x5b];
    gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + ((reg << 2) & mask));

    /* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */
    gfx.bufferOffset = (((Pico_mcd->s68k_regs[0x5c+1] & 0x1f) + 1) << 6) - 7;

    /* image buffer start index in dot units (2 pixels/byte) */
    reg = (Pico_mcd->s68k_regs[0x5e] << 8) | Pico_mcd->s68k_regs[0x5f];
    gfx.bufferStart = (reg << 3) & 0x7ffc0;

    /* add image buffer horizontal dot offset */
    gfx.bufferStart += (Pico_mcd->s68k_regs[0x60+1] & 0x3f);

    /* reset GFX chip cycle counter */
    //gfx.cycles = cycles;

    /* update GFX chip timings (see AC3:Thunderhawk / Thunderstrike) */
    //gfx.cyclesPerLine = 4 * 5 * scd.regs[0x62>>1].w;

    /* start graphics operation */
    Pico_mcd->s68k_regs[0x58] = 0x80;
    Pico_mcd->m.state_flags &= ~PCD_ST_S68K_POLL;
    Pico_mcd->m.s68k_poll_cnt = 0;

    gfx_schedule();
  }
}

/* PicoDrive specific */
#define UPDATE_CYCLES 20000

static void gfx_schedule(void)
{
  int w, h, cycles;
  int y_step;

  w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63];
  h = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65];

  cycles = 5 * w * h;
  y_step = h;
  if (cycles > UPDATE_CYCLES)
    y_step = (UPDATE_CYCLES + 5 * w - 1) / (5 * w);

  gfx.y_step = y_step;
  pcd_event_schedule_s68k(PCD_EVENT_GFX, 5 * w * y_step);
}

void gfx_update(unsigned int cycles)
{
  int lines, lines_reg;
  int w;

  if (!(Pico_mcd->s68k_regs[0x58] & 0x80))
    return;

  w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63];
  lines = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65];
  lines_reg = lines - gfx.y_step;

  if (lines_reg <= 0) {
    Pico_mcd->s68k_regs[0x58] = 0;
    Pico_mcd->s68k_regs[0x64] =
    Pico_mcd->s68k_regs[0x65] = 0;

    Pico_mcd->m.state_flags &= ~PCD_ST_S68K_POLL;
    Pico_mcd->m.s68k_poll_cnt = 0;
    if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN1) {
      elprintf(EL_INTS|EL_CD, "s68k: gfx_cd irq 1");
      pcd_irq_s68k(1, 1);
    }
  }
  else {
    Pico_mcd->s68k_regs[0x64] = lines_reg >> 8;
    Pico_mcd->s68k_regs[0x65] = lines_reg;

    if (lines > gfx.y_step)
      lines = gfx.y_step;

    pcd_event_schedule(cycles, PCD_EVENT_GFX, 5 * w * lines);
  }

  if (PicoIn.opt & POPT_EN_MCD_GFX)
  {
    /* render lines */
    while (lines--)
    {
      /* process dots to image buffer */
      gfx_render(gfx.bufferStart, w);

      /* increment image buffer start index for next line (8 pixels/line) */
      gfx.bufferStart += 8;
    }
  }
}

// vim:shiftwidth=2:ts=2:expandtab
Commit	Line	Data
e53f0499	1	/***************************************************************************************
	2	* Genesis Plus
	3	* CD graphics processor
	4	*
	5	* Copyright (C) 2012 Eke-Eke (Genesis Plus GX)
	6	*
	7	* Redistribution and use of this code or any derivative works are permitted
	8	* provided that the following conditions are met:
	9	*
	10	* - Redistributions may not be sold, nor may they be used in a commercial
	11	* product or activity.
	12	*
	13	* - Redistributions that are modified from the original source must include the
	14	* complete source code, including the source code for all components used by a
	15	* binary built from the modified sources. However, as a special exception, the
	16	* source code distributed need not include anything that is normally distributed
	17	* (in either source or binary form) with the major components (compiler, kernel,
	18	* and so on) of the operating system on which the executable runs, unless that
	19	* component itself accompanies the executable.
	20	*
	21	* - Redistributions must reproduce the above copyright notice, this list of
	22	* conditions and the following disclaimer in the documentation and/or other
	23	* materials provided with the distribution.
	24	*
	25	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	26	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	27	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	28	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	29	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	30	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	31	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	32	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	33	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	34	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	35	* POSSIBILITY OF SUCH DAMAGE.
	36	*
	37	****************************************************************************************/
a93a80de	38	#include "../pico_int.h"
a93a80de	39	#include "genplus_macros.h"
e53f0499	40
	41	typedef struct
	42	{
a93a80de	43	//uint32 cycles; /* current cycles count for graphics operation */
a93a80de	44	//uint32 cyclesPerLine; /* current graphics operation timings */
e53f0499	45	uint32 dotMask; /* stamp map size mask */
f9b966de	46	uint32 stampMask; /* stamp number mask */
e53f0499	47	uint16 tracePtr; / trace vector pointer */
	48	uint16 mapPtr; / stamp map table base address */
	49	uint8 stampShift; /* stamp pixel shift value (related to stamp size) */
	50	uint8 mapShift; /* stamp map table shift value (related to stamp map size) */
	51	uint16 bufferOffset; /* image buffer column offset */
	52	uint32 bufferStart; /* image buffer start index */
a93a80de	53	uint32 y_step; /* pico: render line step */
f3cb39f2	54	uint8 lut_prio[4][0x10][0x10]; /* WORD-RAM data writes priority lookup table */
e53f0499	55	uint8 lut_pixel[0x200]; /* Graphics operation dot offset lookup table */
b633247f	56	uint16 lut_cell2[0x80]; /* Graphics operation stamp offset lookup table */
b633247f	57	uint16 lut_cell4[0x80]; /* Graphics operation stamp offset lookup table */
e53f0499	58	} gfx_t;
	59
	60	static gfx_t gfx;
	61
a93a80de	62	static void gfx_schedule(void);
a93a80de	63
e53f0499	64	/***************************************************************/
	65	/* Rotation / Scaling operation (2M Mode) */
	66	/***************************************************************/
	67
	68	void gfx_init(void)
	69	{
	70	int i, j;
b633247f	71	uint8 row, col, temp;
e53f0499	72
	73	memset(&gfx, 0, sizeof(gfx));
	74
	75	/* Initialize priority modes lookup table */
f3cb39f2	76	for (i = 0; i < 0x10; i++)
e53f0499	77	{
f3cb39f2	78	for (j = 0; j < 0x10; j++)
e53f0499	79	{
	80	/* normal */
	81	gfx.lut_prio[0][i][j] = j;
	82	/* underwrite */
f3cb39f2	83	gfx.lut_prio[1][i][j] = i ? i : j;
e53f0499	84	/* overwrite */
f3cb39f2	85	gfx.lut_prio[2][i][j] = j ? j : i;
e53f0499	86	/* invalid */
	87	gfx.lut_prio[3][i][j] = i;
	88	}
	89	}
	90
	91	/* Initialize cell lookup table */
7ce6a6d1	92	/* table entry = yyxxhrr (7 bits) */
e53f0499	93	/* with: yy = cell row (0-3) */
e53f0499	94	/* xx = cell column (0-3) */
e53f0499	95	/* hrr = HFLIP & ROTATION bits */
b633247f	96	for (i=0; i<0x80; i++)
e53f0499	97	{
e53f0499	98	/* one stamp = 2x2 cells (16x16) or 4x4 cells (32x32) */
b633247f	99	row = (i >> 5) & 3;
b633247f	100	col = (i >> 3) & 3;
e53f0499	101
b633247f	102	if (i & 4) { col = col ^ 3; } /* HFLIP (always first) */
	103	if (i & 2) { col = col ^ 3; row = row ^ 3; } /* ROLL1 */
	104	if (i & 1) { temp = col; col = row ^ 3; row = temp; } /* ROLL0 */
e53f0499	105
e53f0499	106	/* cell offset (0-3 or 0-15) */
b633247f	107	gfx.lut_cell2[i] = ((row&1) + (col&1) * 2) << 6;
b633247f	108	gfx.lut_cell4[i] = ((row&3) + (col&3) * 4) << 6;
e53f0499	109	}
	110
	111	/* Initialize pixel lookup table */
	112	/* table entry = yyyxxxhrr (9 bits) */
	113	/* with: yyy = pixel row (0-7) */
	114	/* xxx = pixel column (0-7) */
	115	/* hrr = HFLIP & ROTATION bits */
	116	for (i=0; i<0x200; i++)
	117	{
	118	/* one cell = 8x8 pixels */
	119	row = (i >> 6) & 7;
	120	col = (i >> 3) & 7;
	121
	122	if (i & 4) { col = col ^ 7; } /* HFLIP (always first) */
	123	if (i & 2) { col = col ^ 7; row = row ^ 7; } /* ROLL1 */
	124	if (i & 1) { temp = col; col = row ^ 7; row = temp; } /* ROLL0 */
	125
	126	/* pixel offset (0-63) */
	127	gfx.lut_pixel[i] = col + row * 8;
	128	}
	129	}
	130
e53f0499	131	int gfx_context_save(uint8 *state)
	132	{
	133	uint32 tmp32;
	134	int bufferptr = 0;
	135
a93a80de	136	//save_param(&gfx.cycles, sizeof(gfx.cycles));
a93a80de	137	//save_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine));
e53f0499	138	save_param(&gfx.dotMask, sizeof(gfx.dotMask));
	139	save_param(&gfx.stampShift, sizeof(gfx.stampShift));
	140	save_param(&gfx.mapShift, sizeof(gfx.mapShift));
	141	save_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset));
	142	save_param(&gfx.bufferStart, sizeof(gfx.bufferStart));
	143
a93a80de	144	tmp32 = (uint8 *)(gfx.tracePtr) - Pico_mcd->word_ram2M;
e53f0499	145	save_param(&tmp32, 4);
e53f0499	146
a93a80de	147	tmp32 = (uint8 *)(gfx.mapPtr) - Pico_mcd->word_ram2M;
e53f0499	148	save_param(&tmp32, 4);
e53f0499	149
a93a80de	150	save_param(&gfx.y_step, sizeof(gfx.y_step));
a93a80de	151
e53f0499	152	return bufferptr;
	153	}
	154
a93a80de	155	int gfx_context_load(const uint8 *state)
e53f0499	156	{
	157	uint32 tmp32;
	158	int bufferptr = 0;
	159
a93a80de	160	//load_param(&gfx.cycles, sizeof(gfx.cycles));
a93a80de	161	//load_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine));
e53f0499	162	load_param(&gfx.dotMask, sizeof(gfx.dotMask));
	163	load_param(&gfx.stampShift, sizeof(gfx.stampShift));
	164	load_param(&gfx.mapShift, sizeof(gfx.mapShift));
	165	load_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset));
	166	load_param(&gfx.bufferStart, sizeof(gfx.bufferStart));
	167
	168	load_param(&tmp32, 4);
a93a80de	169	gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32);
e53f0499	170
e53f0499	171	load_param(&tmp32, 4);
a93a80de	172	gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32);
	173
	174	load_param(&gfx.y_step, sizeof(gfx.y_step));
e53f0499	175
	176	return bufferptr;
	177	}
	178
b633247f	179	static inline int gfx_pixel(uint32 xpos, uint32 ypos, uint16 *lut_cell)
e53f0499	180	{
e53f0499	181	uint16 stamp_data;
e53f0499	182	uint32 stamp_index;
b633247f	183	uint8 pixel_out = 0x00;
	184
	185	/* check if pixel is outside stamp map */
	186	if (((xpos \| ypos) & ~gfx.dotMask) == 0)
	187	{
	188	/* read stamp map table data */
	189	stamp_data = gfx.mapPtr[(xpos >> gfx.stampShift) \| ((ypos >> gfx.stampShift) << gfx.mapShift)];
	190
	191	/* stamp generator base index */
	192	/* sss ssssssss ccyyyxxx (16x16) or sss sssssscc ccyyyxxx (32x32) */
	193	/* with: s = stamp number (1 stamp = 16x16 or 32x32 pixels) */
	194	/* c = cell offset (0-3 for 16x16, 0-15 for 32x32) */
	195	/* yyy = line offset (0-7) */
	196	/* xxx = pixel offset (0-7) */
f9b966de	197	stamp_index = (stamp_data & gfx.stampMask) << 8;
b633247f	198
	199	if (stamp_index)
	200	{
	201	/* extract HFLIP & ROTATION bits */
	202	stamp_data = (stamp_data >> 13) & 7;
	203
	204	/* cell offset (0-3 or 0-15) */
7ce6a6d1	205	/* table entry = yyxxhrr (7 bits) */
b633247f	206	/* with: yy = cell row (0-3) = (ypos >> (11 + 3)) & 3 */
	207	/* xx = cell column (0-3) = (xpos >> (11 + 3)) & 3 */
	208	/* hrr = HFLIP & ROTATION bits */
	209	stamp_index \|= lut_cell[stamp_data \| ((ypos >> 9) & 0x60) \| ((xpos >> 11) & 0x18)];
	210
	211	/* pixel offset (0-63) */
	212	/* table entry = yyyxxxhrr (9 bits) */
	213	/* with: yyy = pixel row (0-7) = (ypos >> 11) & 7 */
	214	/* xxx = pixel column (0-7) = (xpos >> 11) & 7 */
	215	/* hrr = HFLIP & ROTATION bits */
7ce6a6d1	216	stamp_index \|= gfx.lut_pixel[stamp_data \| ((ypos >> 5) & 0x1c0) \| ((xpos >> 8) & 0x38)];
b633247f	217
	218	/* read pixel pair (2 pixels/byte) */
	219	pixel_out = READ_BYTE(Pico_mcd->word_ram2M, stamp_index >> 1);
	220
7ce6a6d1	221	/* extract left or right pixel */
7ce6a6d1	222	pixel_out >>= 4 * !(stamp_index & 1);
b633247f	223	pixel_out &= 0x0f;
	224	}
	225	}
	226
	227	return pixel_out;
	228	}
	229
	230	#define RENDER_LOOP(N, UPDP, COND1, COND2) do { \
	231	if (bufferIndex & 1) { \
7ce6a6d1	232	bufferIndex ^= 1; \
b633247f	233	goto right##N; /* no initial left pixel */ \
	234	} \
	235	/* process all dots */ \
	236	while (width--) \
	237	{ \
	238	/* left pixel */ \
	239	xpos &= mask; \
	240	ypos &= mask; \
	241	\
	242	if (COND1) { \
	243	pixel_out = gfx_pixel(xpos, ypos, lut_cell); \
	244	UPDP; \
	245	} \
	246	\
	247	if (COND2) { \
	248	/* read out paired pixel data */ \
	249	pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1); \
	250	\
	251	/* priority mode write */ \
	252	pixel_in = (lut_prio[(pixel_in & 0xf0) >> 4][pixel_out] << 4) \| \
	253	(pixel_in & 0x0f); \
	254	\
	255	/* write data to image buffer */ \
	256	WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_in); \
	257	} \
	258	\
	259	/* increment pixel position */ \
	260	xpos += xoffset; \
	261	ypos += yoffset; \
	262	\
	263	right##N: \
	264	if (width-- == 0) break; \
	265	\
	266	/* right pixel */ \
	267	xpos &= mask; \
	268	ypos &= mask; \
	269	\
	270	if (COND1) { \
	271	pixel_out = gfx_pixel(xpos, ypos, lut_cell); \
	272	UPDP; \
	273	} \
	274	\
	275	if (COND2) { \
	276	/* read out paired pixel data */ \
	277	pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1); \
	278	\
	279	/* priority mode write */ \
	280	pixel_in = (lut_prio[pixel_in & 0x0f][pixel_out]) \| \
	281	(pixel_in & 0xf0); \
	282	\
	283	/* write data to image buffer */ \
	284	WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_in); \
	285	} \
	286	\
	287	/* increment pixel position */ \
	288	xpos += xoffset; \
	289	ypos += yoffset; \
	290	\
	291	/* next pixel */ \
	292	bufferIndex += 2; \
	293	/* check current pixel position */ \
	294	if ((bufferIndex & 7) == 0) \
	295	{ \
	296	/* next cell: increment buffer offset by one column (minus 8 pixels) */ \
297	bufferIndex += gfx.bufferOffset-1; \
298	} \
299	} \
300	} while (0)
301
302	static void gfx_render(uint32 bufferIndex, uint32 width)
303	{
304	uint8 pixel_in, pixel_out;
f3cb39f2	305	uint32 priority;
b633247f	306	uint8 (*lut_prio)[0x10];
	307	uint16 *lut_cell;
	308	uint32 mask;
e53f0499	309
	310	/* pixel map start position for current line (13.3 format converted to 13.11) */
	311	uint32 xpos = *gfx.tracePtr++ << 8;
	312	uint32 ypos = *gfx.tracePtr++ << 8;
	313
	314	/* pixel map offset values for current line (5.11 format) */
	315	uint32 xoffset = (int16) *gfx.tracePtr++;
	316	uint32 yoffset = (int16) *gfx.tracePtr++;
	317
f3cb39f2	318	priority = (Pico_mcd->s68k_regs[2] << 8) \| Pico_mcd->s68k_regs[3];
f3cb39f2	319	priority = (priority >> 3) & 0x03;
b633247f	320	lut_prio = gfx.lut_prio[priority];
f3cb39f2	321
b633247f	322	lut_cell = (Pico_mcd->s68k_regs[0x58+1] & 0x02) ? gfx.lut_cell4 : gfx.lut_cell2;
e53f0499	323
b633247f	324	/* check if stamp map is repeated */
	325	mask = 0xffffff; /* 24-bit range */
	326	if (Pico_mcd->s68k_regs[0x58+1] & 0x01)
	327	{
	328	/* stamp map range */
	329	mask = gfx.dotMask;
	330	}
e53f0499	331
b633247f	332	pixel_out = 0;
	333	if (xoffset+(1U<<10) <= 1U<<11 && yoffset+(1U<<10) <= 1U<<11) {
	334	/* upscaling >= 2x, test for duplicate pixels to avoid recalculation */
	335	uint32 oldx, oldy;
	336	oldx = oldy = ~xpos;
	337	RENDER_LOOP(1, oldx = xpos;oldy = ypos, (oldx^xpos ^ oldy^ypos) >> 11, (!priority) \| pixel_out);
	338	} else {
	339	RENDER_LOOP(3, , 1, (!priority) \| pixel_out);
e53f0499	340	}
	341	}
	342
f821bb70	343	void gfx_start(uint32 base)
e53f0499	344	{
e53f0499	345	/* make sure 2M mode is enabled */
a93a80de	346	if (!(Pico_mcd->s68k_regs[3] & 0x04))
e53f0499	347	{
9770f531	348	uint32 mask = 0;
a93a80de	349	uint32 reg;
e53f0499	350
e53f0499	351	/* trace vector pointer */
a93a80de	352	gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + ((base << 2) & 0x3fff8));
e53f0499	353
e53f0499	354	/* stamps & stamp map size */
a93a80de	355	switch ((Pico_mcd->s68k_regs[0x58+1] >> 1) & 0x03)
e53f0499	356	{
	357	case 0:
	358	gfx.dotMask = 0x07ffff; /* 256x256 dots/map */
f9b966de	359	gfx.stampMask = 0x7ff; /* 16x16 dots/stamp */
f9b966de	360	gfx.stampShift = 11 + 4; /* 16x16 dots/stamp */
e53f0499	361	gfx.mapShift = 4; /* 16x16 stamps/map */
	362	mask = 0x3fe00; /* 512 bytes/table */
	363	break;
	364
	365	case 1:
	366	gfx.dotMask = 0x07ffff; /* 256x256 dots/map */
f9b966de	367	gfx.stampMask = 0x7fc; /* 16x16 dots/stamp */
f9b966de	368	gfx.stampShift = 11 + 5; /* 32x32 dots/stamp */
e53f0499	369	gfx.mapShift = 3; /* 8x8 stamps/map */
	370	mask = 0x3ff80; /* 128 bytes/table */
	371	break;
	372
	373	case 2:
	374	gfx.dotMask = 0x7fffff; /* 40964096 dots/map /
f9b966de	375	gfx.stampMask = 0x7ff; /* 16x16 dots/stamp */
f9b966de	376	gfx.stampShift = 11 + 4; /* 16x16 dots/stamp */
e53f0499	377	gfx.mapShift = 8; /* 256x256 stamps/map */
	378	mask = 0x20000; /* 131072 bytes/table */
	379	break;
	380
	381	case 3:
	382	gfx.dotMask = 0x7fffff; /* 40964096 dots/map /
f9b966de	383	gfx.stampMask = 0x7fc; /* 16x16 dots/stamp */
f9b966de	384	gfx.stampShift = 11 + 5; /* 32x32 dots/stamp */
e53f0499	385	gfx.mapShift = 7; /* 128x128 stamps/map */
	386	mask = 0x38000; /* 32768 bytes/table */
	387	break;
	388	}
	389
	390	/* stamp map table base address */
a93a80de	391	reg = (Pico_mcd->s68k_regs[0x5a] << 8) \| Pico_mcd->s68k_regs[0x5b];
a93a80de	392	gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + ((reg << 2) & mask));
e53f0499	393
e53f0499	394	/* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */
a93a80de	395	gfx.bufferOffset = (((Pico_mcd->s68k_regs[0x5c+1] & 0x1f) + 1) << 6) - 7;
e53f0499	396
e53f0499	397	/* image buffer start index in dot units (2 pixels/byte) */
a93a80de	398	reg = (Pico_mcd->s68k_regs[0x5e] << 8) \| Pico_mcd->s68k_regs[0x5f];
a93a80de	399	gfx.bufferStart = (reg << 3) & 0x7ffc0;
e53f0499	400
e53f0499	401	/* add image buffer horizontal dot offset */
a93a80de	402	gfx.bufferStart += (Pico_mcd->s68k_regs[0x60+1] & 0x3f);
e53f0499	403
e53f0499	404	/* reset GFX chip cycle counter */
a93a80de	405	//gfx.cycles = cycles;
e53f0499	406
e53f0499	407	/* update GFX chip timings (see AC3:Thunderhawk / Thunderstrike) */
a93a80de	408	//gfx.cyclesPerLine = 4 * 5 * scd.regs[0x62>>1].w;
e53f0499	409
e53f0499	410	/* start graphics operation */
a93a80de	411	Pico_mcd->s68k_regs[0x58] = 0x80;
4985bad0	412	Pico_mcd->m.state_flags &= ~PCD_ST_S68K_POLL;
4985bad0	413	Pico_mcd->m.s68k_poll_cnt = 0;
a93a80de	414
a93a80de	415	gfx_schedule();
e53f0499	416	}
	417	}
	418
a93a80de	419	/* PicoDrive specific */
	420	#define UPDATE_CYCLES 20000
	421
	422	static void gfx_schedule(void)
e53f0499	423	{
a93a80de	424	int w, h, cycles;
a93a80de	425	int y_step;
e53f0499	426
a93a80de	427	w = (Pico_mcd->s68k_regs[0x62] << 8) \| Pico_mcd->s68k_regs[0x63];
a93a80de	428	h = (Pico_mcd->s68k_regs[0x64] << 8) \| Pico_mcd->s68k_regs[0x65];
e53f0499	429
a93a80de	430	cycles = 5 * w * h;
7ce6a6d1	431	y_step = h;
a93a80de	432	if (cycles > UPDATE_CYCLES)
a93a80de	433	y_step = (UPDATE_CYCLES + 5 * w - 1) / (5 * w);
e53f0499	434
a93a80de	435	gfx.y_step = y_step;
	436	pcd_event_schedule_s68k(PCD_EVENT_GFX, 5 * w * y_step);
	437	}
e53f0499	438
a93a80de	439	void gfx_update(unsigned int cycles)
	440	{
	441	int lines, lines_reg;
	442	int w;
e53f0499	443
a93a80de	444	if (!(Pico_mcd->s68k_regs[0x58] & 0x80))
a93a80de	445	return;
e53f0499	446
a93a80de	447	w = (Pico_mcd->s68k_regs[0x62] << 8) \| Pico_mcd->s68k_regs[0x63];
	448	lines = (Pico_mcd->s68k_regs[0x64] << 8) \| Pico_mcd->s68k_regs[0x65];
	449	lines_reg = lines - gfx.y_step;
	450
	451	if (lines_reg <= 0) {
	452	Pico_mcd->s68k_regs[0x58] = 0;
	453	Pico_mcd->s68k_regs[0x64] =
	454	Pico_mcd->s68k_regs[0x65] = 0;
	455
4985bad0	456	Pico_mcd->m.state_flags &= ~PCD_ST_S68K_POLL;
4985bad0	457	Pico_mcd->m.s68k_poll_cnt = 0;
a93a80de	458	if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN1) {
a93a80de	459	elprintf(EL_INTS\|EL_CD, "s68k: gfx_cd irq 1");
eb36d9c7	460	pcd_irq_s68k(1, 1);
e53f0499	461	}
a93a80de	462	}
	463	else {
	464	Pico_mcd->s68k_regs[0x64] = lines_reg >> 8;
	465	Pico_mcd->s68k_regs[0x65] = lines_reg;
	466
	467	if (lines > gfx.y_step)
	468	lines = gfx.y_step;
	469
	470	pcd_event_schedule(cycles, PCD_EVENT_GFX, 5 * w * lines);
	471	}
e53f0499	472
93f9619e	473	if (PicoIn.opt & POPT_EN_MCD_GFX)
a93a80de	474	{
e53f0499	475	/* render lines */
	476	while (lines--)
	477	{
	478	/* process dots to image buffer */
a93a80de	479	gfx_render(gfx.bufferStart, w);
e53f0499	480
	481	/* increment image buffer start index for next line (8 pixels/line) */
	482	gfx.bufferStart += 8;
	483	}
	484	}
	485	}
a93a80de	486
a93a80de	487	// vim:shiftwidth=2:ts=2:expandtab