/*
* Glide64 - Glide video plugin for Nintendo 64 emulators.
* Copyright (c) 2002  Dave2001
*
* 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
* 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
*/

//****************************************************************
//
// Glide64 - Glide Plugin for Nintendo 64 emulators (tested mostly with Project64)
// Project started on December 29th, 2001
//
// To modify Glide64:
// * Write your name and (optional)email, commented by your work, so I know who did it, and so that you can find which parts you modified when it comes time to send it to me.
// * Do NOT send me the whole project or file that you modified.  Take out your modified code sections, and tell me where to put them.  If people sent the whole thing, I would have many different versions, but no idea how to combine them all.
//
// Official Glide64 development channel: #Glide64 on EFnet
//
// Original author: Dave2001 (Dave2999@hotmail.com)
// Other authors: Gonetz, Gugaman
//
//****************************************************************

//****************************************************************
// uCode 4 - RSP SW 2.0D EXT
//****************************************************************

static void uc4_vertex()
{
  DWORD addr = segoffset(rdp.cmd1) & 0x00FFFFFF;
  int v0, i, n;
  float x, y, z;

  rdp.v0 = v0 = 0;     // Current vertex
  rdp.vn = n = ((rdp.cmd0 >> 4) & 0xFFF) / 33 + 1; // Number of vertices to copy

  FRDP("uc4:vertex: v0: %d, n: %d\n", v0, n);

  // This is special, not handled in update(), but here
  // * Matrix Pre-multiplication idea by Gonetz (Gonetz@ngs.ru)
  if (rdp.update & UPDATE_MULT_MAT)
  {
    rdp.update ^= UPDATE_MULT_MAT;
    MulMatrices(rdp.model, rdp.proj, rdp.combined);
  }
  // *

  // This is special, not handled in update()
  if (rdp.update & UPDATE_LIGHTS)
  {
    rdp.update ^= UPDATE_LIGHTS;
    
    // Calculate light vectors
    for (DWORD l=0; l<rdp.num_lights; l++)
    {
      InverseTransformVector(&rdp.light[l].dir_x, rdp.light_vector[l], rdp.model);
      NormalizeVector (rdp.light_vector[l]);
    }
  }

  for (i=0; i < (n<<4); i+=16)
  {
    VERTEX *v = &rdp.vtx[v0 + (i>>4)];
    x   = (float)((short*)gfx.RDRAM)[(((addr+i) >> 1) + 0)^1];
    y   = (float)((short*)gfx.RDRAM)[(((addr+i) >> 1) + 1)^1];
    z   = (float)((short*)gfx.RDRAM)[(((addr+i) >> 1) + 2)^1];
    v->flags  = ((WORD*)gfx.RDRAM)[(((addr+i) >> 1) + 3)^1];
    v->ou   = (float)((short*)gfx.RDRAM)[(((addr+i) >> 1) + 4)^1] * rdp.tiles[rdp.cur_tile].s_scale;
    v->ov   = (float)((short*)gfx.RDRAM)[(((addr+i) >> 1) + 5)^1] * rdp.tiles[rdp.cur_tile].t_scale;
    v->a    = ((BYTE*)gfx.RDRAM)[(addr+i + 15)^3];

    v->x = x*rdp.combined[0][0] + y*rdp.combined[1][0] + z*rdp.combined[2][0] + rdp.combined[3][0];
    v->y = x*rdp.combined[0][1] + y*rdp.combined[1][1] + z*rdp.combined[2][1] + rdp.combined[3][1];
    v->z = x*rdp.combined[0][2] + y*rdp.combined[1][2] + z*rdp.combined[2][2] + rdp.combined[3][2];
    v->w = x*rdp.combined[0][3] + y*rdp.combined[1][3] + z*rdp.combined[2][3] + rdp.combined[3][3];

    v->oow = 1.0f / v->w;
    v->x_w = v->x * v->oow;
    v->y_w = v->y * v->oow;
    v->z_w = v->z * v->oow;
    CalculateFog (v);

    v->uv_calculated = 0xFFFFFFFF;
    v->screen_translated = 0;
    v->shade_mods_allowed = 1;

    v->scr_off = 0;
    if (v->x < -v->w) v->scr_off |= 1;
    if (v->x > v->w) v->scr_off |= 2;
    if (v->y < -v->w) v->scr_off |= 4;
    if (v->y > v->w) v->scr_off |= 8;
    if (v->w < 0.1f) v->scr_off |= 16;

    if (rdp.geom_mode & 0x00020000)
    {
      v->vec[0] = ((char*)gfx.RDRAM)[(addr+i + 12)^3];
      v->vec[1] = ((char*)gfx.RDRAM)[(addr+i + 13)^3];
      v->vec[2] = ((char*)gfx.RDRAM)[(addr+i + 14)^3];

      if (rdp.geom_mode & 0x80000) 
        calc_linear (v);
      else if (rdp.geom_mode & 0x40000) 
        calc_sphere (v);

      NormalizeVector (v->vec);
      calc_light (v);
    }
    else
    {
      v->r = ((BYTE*)gfx.RDRAM)[(addr+i + 12)^3];
      v->g = ((BYTE*)gfx.RDRAM)[(addr+i + 13)^3];
      v->b = ((BYTE*)gfx.RDRAM)[(addr+i + 14)^3];
    }
  }
}

static void uc4_tri1()
{
  int v1 = ((rdp.cmd1 >> 16) & 0xFF) / 5;
  int v2 = ((rdp.cmd1 >> 8) & 0xFF) / 5;
  int v3 = (rdp.cmd1 & 0xFF) / 5;
  FRDP("uc4:tri1 #%d - %d, %d, %d\n", rdp.tri_n,
    v1, v2, v3);

  VERTEX *v[3] = {
    &rdp.vtx[v1],
    &rdp.vtx[v2],
    &rdp.vtx[v3]
  };

  if (cull_tri(v))
    rdp.tri_n ++;
  else
  {
    update ();

    DrawTri (v);
    rdp.tri_n ++;
  }
}

static void uc4_quad3d()
{
  FRDP("uc4:quad3d #%d, #%d\n", rdp.tri_n, rdp.tri_n+1);

  VERTEX *v[6] = {
    &rdp.vtx[((rdp.cmd1 >> 24) & 0xFF) / 5],
    &rdp.vtx[((rdp.cmd1 >> 16) & 0xFF) / 5],
    &rdp.vtx[((rdp.cmd1 >> 8) & 0xFF) / 5],
    &rdp.vtx[((rdp.cmd1 >> 24) & 0xFF) / 5],
    &rdp.vtx[((rdp.cmd1 >> 8) & 0xFF) / 5],
    &rdp.vtx[(rdp.cmd1 & 0xFF) / 5]
  };

  BOOL updated = 0;

  if (cull_tri(v))
    rdp.tri_n ++;
  else
  {
    updated = 1;
    update ();

    DrawTri (v);
    rdp.tri_n ++;
  }

  if (cull_tri(v+3))
    rdp.tri_n ++;
  else
  {
    if (!updated)
      update ();

    DrawTri (v+3);
    rdp.tri_n ++;
  }
}