/******************************************************************************/
/* Mednafen Sega Saturn Emulation Module                                      */
/******************************************************************************/
/* vdp1_poly.cpp - VDP1 Polygon Drawing Commands Emulation
**  Copyright (C) 2015-2020 Mednafen Team
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public License
** as published by the Free Software Foundation; either version 2
** of the License, or (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software Foundation, Inc.,
** 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

#include "ss.h"
#include "vdp1_common.h"

namespace MDFN_IEN_SS
{

namespace VDP1
{

static int32 (*LineFuncTab[2][3][0x20][8 + 1])(bool* need_line_resume) =
{
 #define LINEFN_BC(die, bpp8, b, c)	\
	DrawLine<true, false, die, bpp8, c == 0x8, (bool)(b & 0x10), (b & 0x10) && (b & 0x08), (bool)(b & 0x04), false/*b & 0x02*/, (bool)(b & 0x01), (bool)(c & 0x4), (bool)(c & 0x2), (bool)(c & 0x1)>

 #define LINEFN_B(die, bpp8, b)									\
	{										\
	 LINEFN_BC(die, bpp8, b, 0x0), LINEFN_BC(die, bpp8, b, 0x1), LINEFN_BC(die, bpp8, b, 0x2), LINEFN_BC(die, bpp8, b, 0x3),	\
	 LINEFN_BC(die, bpp8, b, 0x4), LINEFN_BC(die, bpp8, b, 0x5), LINEFN_BC(die, bpp8, b, 0x6), LINEFN_BC(die, bpp8, b, 0x7), 	\
	 LINEFN_BC(die, bpp8, b, 0x8), 	/* msb on */						\
	}

 #define LINEFN_BPP8(die, bpp8)									\
 {												\
  LINEFN_B(die, bpp8, 0x00), LINEFN_B(die, bpp8, 0x01), LINEFN_B(die, bpp8, 0x02), LINEFN_B(die, bpp8, 0x03),	\
  LINEFN_B(die, bpp8, 0x04), LINEFN_B(die, bpp8, 0x05), LINEFN_B(die, bpp8, 0x06), LINEFN_B(die, bpp8, 0x07),	\
  LINEFN_B(die, bpp8, 0x08), LINEFN_B(die, bpp8, 0x09), LINEFN_B(die, bpp8, 0x0A), LINEFN_B(die, bpp8, 0x0B),	\
  LINEFN_B(die, bpp8, 0x0C), LINEFN_B(die, bpp8, 0x0D), LINEFN_B(die, bpp8, 0x0E), LINEFN_B(die, bpp8, 0x0F),	\
												\
  LINEFN_B(die, bpp8, 0x10), LINEFN_B(die, bpp8, 0x11), LINEFN_B(die, bpp8, 0x12), LINEFN_B(die, bpp8, 0x13),	\
  LINEFN_B(die, bpp8, 0x14), LINEFN_B(die, bpp8, 0x15), LINEFN_B(die, bpp8, 0x16), LINEFN_B(die, bpp8, 0x17),	\
  LINEFN_B(die, bpp8, 0x18), LINEFN_B(die, bpp8, 0x19), LINEFN_B(die, bpp8, 0x1A), LINEFN_B(die, bpp8, 0x1B),	\
  LINEFN_B(die, bpp8, 0x1C), LINEFN_B(die, bpp8, 0x1D), LINEFN_B(die, bpp8, 0x1E), LINEFN_B(die, bpp8, 0x1F),	\
 }

 {
  LINEFN_BPP8(false, 0),
  LINEFN_BPP8(false, 1),
  LINEFN_BPP8(false, 2),
 },
 {
  LINEFN_BPP8(true, 0),
  LINEFN_BPP8(true, 1),
  LINEFN_BPP8(true, 2),
 }


 #undef LINEFN_BPP8
 #undef LINEFN_B
 #undef LINEFN_BC
};

template<bool gourauden>
static int32 PolygonResumeBase(const uint16* cmd_data)
{
 const uint16 mode = cmd_data[0x2];
 // Abusing the SPD bit passed to the line draw function to denote non-transparency when == 1, transparent when == 0.
 const bool SPD_Opaque = (((mode >> 3) & 0x7) < 0x6) ? ((int32)(TexFetchTab[(mode >> 3) & 0x1F](0xFFFFFFFF)) >= 0) : true;
 auto* const fnptr = LineFuncTab[(bool)(FBCR & FBCR_DIE)][(TVMR & TVMR_8BPP) ? ((TVMR & TVMR_ROTATE) ? 2 : 1) : 0][((mode >> 6) & 0x1E) | SPD_Opaque /*(mode >> 6) & 0x1F*/][(mode & 0x8000) ? 8 : (mode & 0x7)];
 //
 // Don't merge e0 and e1 into a single array, keeping them separate is a workaround for gcc bug #113255
 //
 EdgeStepper e0 = PrimData.e[0];
 EdgeStepper e1 = PrimData.e[1];
 int32 iter = PrimData.iter;
 int32 ret = 0;
 //
 //
 if(MDFN_UNLIKELY(PrimData.need_line_resume))
 {
  PrimData.need_line_resume = false;
  goto ResumeLine;
 }

 if(iter >= 0)
 {
  do
  {
   //printf("x=0x%03x y=0x%03x x_error=0x%04x y_error=0x%04x --- x_error_inc=0x%04x, x_error_adj=0x%04x --- y_error_inc=0x%04x, y_error_adj=0x%04x\n", e[0].x & 0x7FF, e[0].y & 0x7FF, (uint32)e[0].x_error >> (32 - 13), (uint32)e[0].y_error >> (32 - 13), (uint32)e[0].x_error_inc >> (32 - 13), (uint32)e[0].x_error_adj >> (32 - 13), (uint32)e[0].y_error_inc >> (32 - 13), (uint32)e[0].y_error_adj >> (32 - 13));

   e0.GetVertex<gourauden>(&LineData.p[0]);
   e1.GetVertex<gourauden>(&LineData.p[1]);

#if 0
   printf("(Edge0: x=%u y=%u, d_error=0x%04x x_error=0x%04x y_error=0x%04x) ", LineData.p[0].x, LineData.p[0].y, (e[0].d_error + e[0].d_error_inc) >> (32 - 13), (e[0].x_error + e[0].x_error_inc) >> (32 - 13), (e[0].y_error + e[0].y_error_inc) >> (32 - 13));
   printf("(Edge1: x=%u y=%u, d_error=0x%04x x_error=0x%04x y_error=0x%04x)\n", LineData.p[1].x, LineData.p[1].y, (e[1].d_error + e[1].d_error_inc) >> (32 - 13), (e[1].x_error + e[1].x_error_inc) >> (32 - 13), (e[1].y_error + e[1].y_error_inc) >> (32 - 13));
#endif
   //printf("%d,%d %d,%d\n", LineData.p[0].x, LineData.p[0].y, LineData.p[1].x, LineData.p[1].y);
   //
   if(!SetupDrawLine(&ret, true, false, mode) || !iter)
   {
    //
    //printf("%d:%d -> %d:%d\n", lp[0].x, lp[0].y, lp[1].x, lp[1].y);
    ResumeLine:;
    ret += AdjustDrawTiming(fnptr(&PrimData.need_line_resume));
    if(MDFN_UNLIKELY(PrimData.need_line_resume))
     break;
   }

   e0.Step<gourauden>();
   e1.Step<gourauden>();
  } while(MDFN_LIKELY(--iter >= 0 && ret < VDP1_SuspendResumeThreshold));
 }
 //
 //
 PrimData.e[0] = e0;
 PrimData.e[1] = e1;
 PrimData.iter = iter;

 return ret;
}

int32 RESUME_Polygon(const uint16* cmd_data)
{
 if(cmd_data[0x2] & 0x4) // gouraud
  return PolygonResumeBase<true>(cmd_data);
 else
  return PolygonResumeBase<false>(cmd_data);
}


template<bool gourauden>
static INLINE int32 CMD_PolygonG_T(const uint16* cmd_data)
{
 line_vertex p[4];
 int32 ret = 0;
 //
 //
 LineData.tex_base = 0;
 LineData.color = cmd_data[0x3];
 //
 //
 for(unsigned i = 0; i < 4; i++)
 {
  p[i].x = sign_x_to_s32(13, cmd_data[0x6 + (i << 1)]) + LocalX;
  p[i].y = sign_x_to_s32(13, cmd_data[0x7 + (i << 1)]) + LocalY;
 }

 if(gourauden)
 {
  const uint16* gtb = &VRAM[cmd_data[0xE] << 2];

  ret += 4;
  for(unsigned i = 0; i < 4; i++)
   p[i].g = gtb[i];
 }
 //
 //
 //
 int32 dmax;

 dmax = 		      abs(sign_x_to_s32(13, p[3].x - p[0].x));
 dmax = std::max<int32>(dmax, abs(sign_x_to_s32(13, p[3].y - p[0].y)));
 dmax = std::max<int32>(dmax, abs(sign_x_to_s32(13, p[2].x - p[1].x)));
 dmax = std::max<int32>(dmax, abs(sign_x_to_s32(13, p[2].y - p[1].y)));
 dmax &= 0xFFF;

 PrimData.e[0].Setup(gourauden, p[0], p[3], dmax);
 PrimData.e[1].Setup(gourauden, p[1], p[2], dmax);
 PrimData.iter = dmax;
 PrimData.need_line_resume = false;

 return ret;
}

int32 CMD_Polygon(const uint16* cmd_data)
{
 if(cmd_data[0x2] & 0x4) // gouraud
  return CMD_PolygonG_T<true>(cmd_data);
 else
  return CMD_PolygonG_T<false>(cmd_data);
}


}
}
