text: /*
   * PicoDrive
   * (C) notaz, 2009,2010
   *
   * This work is licensed under the terms of MAME license.
   * See COPYING file in the top-level directory.
   */
  #include "../pico_int.h"
  
  int (*PicoScan32xBegin)(unsigned int num);
  int (*PicoScan32xEnd)(unsigned int num);
  int Pico32xDrawMode;
  
  static void convert_pal555(int invert_prio)
  {
    unsigned int *ps = (void *)Pico32xMem->pal;
    unsigned int *pd = (void *)Pico32xMem->pal_native;
    unsigned int m1 = 0x001f001f;
    unsigned int m2 = 0x03e003e0;
    unsigned int m3 = 0xfc00fc00;
    unsigned int inv = 0;
    int i;
  
    if (invert_prio)
      inv = 0x00200020;
  
    // place prio to LS green bit
    for (i = 0x100/2; i > 0; i--, ps++, pd++) {
      unsigned int t = *ps;
      *pd = (((t & m1) << 11) | ((t & m2) << 1) | ((t & m3) >> 10)) ^ inv;
    }
  
    Pico32x.dirty_pal = 0;
  }
  
  // direct color mode
  #define do_line_dc(pd, p32x, pmd, inv, pmd_draw_code)             \
  {                                                                 \
    const unsigned int m1 = 0x001f;                                 \
    const unsigned int m2 = 0x03e0;                                 \
    const unsigned int m3 = 0x7c00;                                 \
    int i;                                                          \
                                                                    \
    for (i = 320; i > 0; i--, pd++, p32x++, pmd++) {                \
      unsigned short t = *p32x;                                     \
      if ((*pmd & 0x3f) != mdbg && !((t ^ inv) & 0x8000)) {         \
        pmd_draw_code;                                              \
        continue;                                                   \
      }                                                             \
                                                                    \
      *pd = ((t & m1) << 11) | ((t & m2) << 1) | ((t & m3) >> 10);  \
    }                                                               \
  }
  
  // packed pixel mode
  #define do_line_pp(pd, p32x, pmd, pmd_draw_code)                  \
  {                                                                 \
    unsigned short t;                                               \
    int i;                                                          \
    for (i = 320; i > 0; i--, pd++, p32x++, pmd++) {                \
      t = pal[*(unsigned char *)((long)p32x ^ 1)];                  \
      if ((t & 0x20) || (*pmd & 0x3f) == mdbg)                      \
        *pd = t;                                                    \
      else                                                          \
        pmd_draw_code;                                              \
    }                                                               \
  } 
  
  // run length mode
  #define do_line_rl(pd, p32x, pmd, pmd_draw_code)                  \
  {                                                                 \
    unsigned short len, t;                                          \
    int i;                                                          \
    for (i = 320; i > 0; p32x++) {                                  \
      t = pal[*p32x & 0xff];                                        \
      for (len = (*p32x >> 8) + 1; len > 0 && i > 0; len--, i--, pd++, pmd++) { \
        if ((*pmd & 0x3f) == mdbg || (t & 0x20))                    \
          *pd = t;                                                  \
        else                                                        \
          pmd_draw_code;                                            \
      }                                                             \
    }                                                               \
  }
  
  // this is almost never used (Wiz and menu bg gen only)
  void FinalizeLine32xRGB555(int sh, int line)
  {
    unsigned short *pd = DrawLineDest;
    unsigned short *pal = Pico32xMem->pal_native;
    unsigned char  *pmd = HighCol + 8;
    unsigned short *dram, *p32x;
    unsigned char   mdbg;
  
    FinalizeLine555(sh, line);
  
    if ((Pico32x.vdp_regs[0] & P32XV_Mx) == 0 || // 32x blanking
        // XXX: how is 32col mode hadled by real hardware?
        !(Pico.video.reg[12] & 1) || // 32col mode
        !(PicoDrawMask & PDRAW_32X_ON))
    {
      return;
    }
  
    dram = (void *)Pico32xMem->dram[Pico32x.vdp_regs[0x0a/2] & P32XV_FS];
    p32x = dram + dram[line];
    mdbg = Pico.video.reg[7] & 0x3f;
  
    if ((Pico32x.vdp_regs[0] & P32XV_Mx) == 2) { // Direct Color Mode
      int inv_bit = (Pico32x.vdp_regs[0] & P32XV_PRI) ? 0x8000 : 0;
      do_line_dc(pd, p32x, pmd, inv_bit,);
      return;
    }
  
    if (Pico32x.dirty_pal)
      convert_pal555(Pico32x.vdp_regs[0] & P32XV_PRI);
  
    if ((Pico32x.vdp_regs[0] & P32XV_Mx) == 1) { // Packed Pixel Mode
      unsigned char *p32xb = (void *)p32x;
      if (Pico32x.vdp_regs[2 / 2] & P32XV_SFT)
        p32xb++;
      do_line_pp(pd, p32xb, pmd,);
    }
    else { // Run Length Mode
      do_line_rl(pd, p32x, pmd,);
    }
  }
  
  #define MD_LAYER_CODE \
    *dst = palmd[*pmd]
  
  #define PICOSCAN_PRE \
    PicoScan32xBegin(l + (lines_sft_offs & 0xff)); \
    dst = DrawLineDest; \
  
  #define PICOSCAN_POST \
    PicoScan32xEnd(l + (lines_sft_offs & 0xff)); \
  
  #define make_do_loop(name, pre_code, post_code, md_code)        \
  /* Direct Color Mode */                                         \
  static void do_loop_dc##name(unsigned short *dst,               \
      unsigned short *dram, int lines_sft_offs, int mdbg)         \
  {                                                               \
    int inv_bit = (Pico32x.vdp_regs[0] & P32XV_PRI) ? 0x8000 : 0; \
    unsigned char  *pmd = PicoDraw2FB +                           \
                            328 * (lines_sft_offs & 0xff) + 8;    \
    unsigned short *palmd = HighPal;                              \
    unsigned short *p32x;                                         \
    int lines = lines_sft_offs >> 16;                             \
    int l;                                                        \
    (void)palmd;                                                  \
    for (l = 0; l < lines; l++, pmd += 8) {                       \
      pre_code;                                                   \
      p32x = dram + dram[l];                                      \
      do_line_dc(dst, p32x, pmd, inv_bit, md_code);               \
      post_code;                                                  \
    }                                                             \
  }                                                               \
                                                                  \
  /* Packed Pixel Mode */                                         \
  static void do_loop_pp##name(unsigned short *dst,               \
      unsigned short *dram, int lines_sft_offs, int mdbg)         \
  {                                                               \
    unsigned short *pal = Pico32xMem->pal_native;                 \
    unsigned char  *pmd = PicoDraw2FB +                           \
                            328 * (lines_sft_offs & 0xff) + 8;    \
    unsigned short *palmd = HighPal;                              \
    unsigned char  *p32x;                                         \
    int lines = lines_sft_offs >> 16;                             \
    int l;                                                        \
    (void)palmd;                                                  \
    for (l = 0; l < lines; l++, pmd += 8) {                       \
      pre_code;                                                   \
      p32x = (void *)(dram + dram[l]);                            \
      p32x += (lines_sft_offs >> 8) & 1;                          \
      do_line_pp(dst, p32x, pmd, md_code);                        \
      post_code;                                                  \
    }                                                             \
  }                                                               \
                                                                  \
  /* Run Length Mode */                                           \
  static void do_loop_rl##name(unsigned short *dst,               \
      unsigned short *dram, int lines_sft_offs, int mdbg)         \
  {                                                               \
    unsigned short *pal = Pico32xMem->pal_native;                 \
    unsigned char  *pmd = PicoDraw2FB +                           \
                            328 * (lines_sft_offs & 0xff) + 8;    \
    unsigned short *palmd = HighPal;                              \
    unsigned short *p32x;                                         \
    int lines = lines_sft_offs >> 16;                             \
    int l;                                                        \
    (void)palmd;                                                  \
    for (l = 0; l < lines; l++, pmd += 8) {                       \
      pre_code;                                                   \
      p32x = dram + dram[l];                                      \
      do_line_rl(dst, p32x, pmd, md_code);                        \
      post_code;                                                  \
    }                                                             \
  }
  
  #ifdef _ASM_32X_DRAW
  #undef make_do_loop
  #define make_do_loop(name, pre_code, post_code, md_code) \
  extern void do_loop_dc##name(unsigned short *dst,        \
      unsigned short *dram, int lines_offs, int mdbg);     \
  extern void do_loop_pp##name(unsigned short *dst,        \
      unsigned short *dram, int lines_offs, int mdbg);     \
  extern void do_loop_rl##name(unsigned short *dst,        \
      unsigned short *dram, int lines_offs, int mdbg);
  #endif
  
  make_do_loop(,,,)
  make_do_loop(_md, , , MD_LAYER_CODE)
  make_do_loop(_scan, PICOSCAN_PRE, PICOSCAN_POST, )
  make_do_loop(_scan_md, PICOSCAN_PRE, PICOSCAN_POST, MD_LAYER_CODE)
  
  typedef void (*do_loop_func)(unsigned short *dst, unsigned short *dram, int lines, int mdbg);
  enum { DO_LOOP, DO_LOOP_MD, DO_LOOP_SCAN, DO_LOOP_MD_SCAN };
  
  static const do_loop_func do_loop_dc_f[] = { do_loop_dc, do_loop_dc_md, do_loop_dc_scan, do_loop_dc_scan_md };
  static const do_loop_func do_loop_pp_f[] = { do_loop_pp, do_loop_pp_md, do_loop_pp_scan, do_loop_pp_scan_md };
  static const do_loop_func do_loop_rl_f[] = { do_loop_rl, do_loop_rl_md, do_loop_rl_scan, do_loop_rl_scan_md };
  
  void PicoDraw32xLayer(int offs, int lines, int md_bg)
  {
    int have_scan = PicoScan32xBegin != NULL && PicoScan32xEnd != NULL;
    const do_loop_func *do_loop;
    unsigned short *dram;
    int lines_sft_offs;
    int which_func;
  
    DrawLineDest = (char *)DrawLineDestBase + offs * DrawLineDestIncrement;
    dram = Pico32xMem->dram[Pico32x.vdp_regs[0x0a/2] & P32XV_FS];
  
    if (Pico32xDrawMode == PDM32X_BOTH) {
      if (Pico.m.dirtyPal)
        PicoDrawUpdateHighPal();
    }
  
    if ((Pico32x.vdp_regs[0] & P32XV_Mx) == 2)
    {
      // Direct Color Mode
      do_loop = do_loop_dc_f;
      goto do_it;
    }
  
    if (Pico32x.dirty_pal)
      convert_pal555(Pico32x.vdp_regs[0] & P32XV_PRI);
  
    if ((Pico32x.vdp_regs[0] & P32XV_Mx) == 1)
    {
      // Packed Pixel Mode
      do_loop = do_loop_pp_f;
    }
    else
    {
      // Run Length Mode
      do_loop = do_loop_rl_f;
    }
  
  do_it:
    if (Pico32xDrawMode == PDM32X_BOTH)
      which_func = have_scan ? DO_LOOP_MD_SCAN : DO_LOOP_MD;
    else
      which_func = have_scan ? DO_LOOP_SCAN : DO_LOOP;
    lines_sft_offs = (lines << 16) | offs;
    if (Pico32x.vdp_regs[2 / 2] & P32XV_SFT)
      lines_sft_offs |= 1 << 8;
  
    do_loop[which_func](DrawLineDest, dram, lines_sft_offs, md_bg);
  }
  
  // mostly unused, games tend to keep 32X layer on
  void PicoDraw32xLayerMdOnly(int offs, int lines)
  {
    int have_scan = PicoScan32xBegin != NULL && PicoScan32xEnd != NULL;
    unsigned short *dst = (void *)((char *)DrawLineDestBase + offs * DrawLineDestIncrement);
    unsigned char  *pmd = PicoDraw2FB + 328 * offs + 8;
    unsigned short *pal = HighPal;
    int poffs = 0, plen = 320;
    int l, p;
  
    if (!(Pico.video.reg[12] & 1)) {
      // 32col mode
      poffs = 32;
      plen = 256;
    }
  
    if (Pico.m.dirtyPal)
      PicoDrawUpdateHighPal();
  
    dst += poffs;
    for (l = 0; l < lines; l++) {
      if (have_scan) {
        PicoScan32xBegin(l + offs);
        dst = DrawLineDest + poffs;
      }
      for (p = 0; p < plen; p += 4) {
        dst[p + 0] = pal[*pmd++];
        dst[p + 1] = pal[*pmd++];
        dst[p + 2] = pal[*pmd++];
        dst[p + 3] = pal[*pmd++];
      }
      dst = (void *)((char *)dst + DrawLineDestIncrement);
      pmd += 328 - plen;
      if (have_scan)
        PicoScan32xEnd(l + offs);
    }
  }
  
  void PicoDrawSetOutFormat32x(pdso_t which, int use_32x_line_mode)
  {
  #ifdef _ASM_32X_DRAW
    extern void *Pico32xNativePal;
    Pico32xNativePal = Pico32xMem->pal_native;
  #endif
  
    if (which == PDF_RGB555 && use_32x_line_mode) {
      // we'll draw via FinalizeLine32xRGB555 (rare)
      PicoDrawSetInternalBuf(NULL, 0);
      Pico32xDrawMode = PDM32X_OFF;
      return;
    }
  
    // use the same layout as alt renderer
    PicoDrawSetInternalBuf(PicoDraw2FB, 328);
    Pico32xDrawMode = (which == PDF_RGB555) ? PDM32X_32X_ONLY : PDM32X_BOTH;
  }
  
  // vim:shiftwidth=2:ts=2:expandtab
  