// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 1993-2008 Raven Software
//
// 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., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
//-----------------------------------------------------------------------------


#include "h2def.h"
#include "i_system.h"
#include "i_video.h"
#include "i_swap.h"

#define SC_INDEX 0x3c4

byte *screen;
int dirtybox[4];
int usegamma;

byte gammatable[5][256] = {
    {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
     21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
     39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,
     57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
     75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,
     93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108,
     109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122,
     123, 124, 125, 126, 127, 128, 128, 129, 130, 131, 132, 133, 134, 135,
     136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149,
     150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163,
     164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177,
     178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191,
     192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205,
     206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219,
     220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233,
     234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247,
     248, 249, 250, 251, 252, 253, 254, 255},

    {2, 4, 5, 7, 8, 10, 11, 12, 14, 15, 16, 18, 19, 20, 21, 23, 24, 25, 26,
     27, 29, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47,
     48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,
     67, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85,
     86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102,
     103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116,
     117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 129,
     130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
     144, 145, 146, 147, 148, 148, 149, 150, 151, 152, 153, 154, 155, 156,
     157, 158, 159, 160, 161, 162, 163, 163, 164, 165, 166, 167, 168, 169,
     170, 171, 172, 173, 174, 175, 175, 176, 177, 178, 179, 180, 181, 182,
     183, 184, 185, 186, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195,
     196, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 205, 206, 207,
     208, 209, 210, 211, 212, 213, 214, 214, 215, 216, 217, 218, 219, 220,
     221, 222, 222, 223, 224, 225, 226, 227, 228, 229, 230, 230, 231, 232,
     233, 234, 235, 236, 237, 237, 238, 239, 240, 241, 242, 243, 244, 245,
     245, 246, 247, 248, 249, 250, 251, 252, 252, 253, 254, 255},

    {4, 7, 9, 11, 13, 15, 17, 19, 21, 22, 24, 26, 27, 29, 30, 32, 33, 35, 36,
     38, 39, 40, 42, 43, 45, 46, 47, 48, 50, 51, 52, 54, 55, 56, 57, 59, 60,
     61, 62, 63, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 76, 77, 78, 79, 80,
     82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 100,
     101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114,
     114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127,
     128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140,
     141, 142, 143, 144, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153,
     153, 154, 155, 156, 157, 158, 159, 160, 160, 161, 162, 163, 164, 165,
     166, 166, 167, 168, 169, 170, 171, 172, 172, 173, 174, 175, 176, 177,
     178, 178, 179, 180, 181, 182, 183, 183, 184, 185, 186, 187, 188, 188,
     189, 190, 191, 192, 193, 193, 194, 195, 196, 197, 197, 198, 199, 200,
     201, 201, 202, 203, 204, 205, 206, 206, 207, 208, 209, 210, 210, 211,
     212, 213, 213, 214, 215, 216, 217, 217, 218, 219, 220, 221, 221, 222,
     223, 224, 224, 225, 226, 227, 228, 228, 229, 230, 231, 231, 232, 233,
     234, 235, 235, 236, 237, 238, 238, 239, 240, 241, 241, 242, 243, 244,
     244, 245, 246, 247, 247, 248, 249, 250, 251, 251, 252, 253, 254, 254,
     255},

    {8, 12, 16, 19, 22, 24, 27, 29, 31, 34, 36, 38, 40, 41, 43, 45, 47, 49,
     50, 52, 53, 55, 57, 58, 60, 61, 63, 64, 65, 67, 68, 70, 71, 72, 74, 75,
     76, 77, 79, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96,
     98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,
     113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,
     127, 128, 129, 130, 131, 132, 133, 134, 135, 135, 136, 137, 138, 139,
     140, 141, 142, 143, 143, 144, 145, 146, 147, 148, 149, 150, 150, 151,
     152, 153, 154, 155, 155, 156, 157, 158, 159, 160, 160, 161, 162, 163,
     164, 165, 165, 166, 167, 168, 169, 169, 170, 171, 172, 173, 173, 174,
     175, 176, 176, 177, 178, 179, 180, 180, 181, 182, 183, 183, 184, 185,
     186, 186, 187, 188, 189, 189, 190, 191, 192, 192, 193, 194, 195, 195,
     196, 197, 197, 198, 199, 200, 200, 201, 202, 202, 203, 204, 205, 205,
     206, 207, 207, 208, 209, 210, 210, 211, 212, 212, 213, 214, 214, 215,
     216, 216, 217, 218, 219, 219, 220, 221, 221, 222, 223, 223, 224, 225,
     225, 226, 227, 227, 228, 229, 229, 230, 231, 231, 232, 233, 233, 234,
     235, 235, 236, 237, 237, 238, 238, 239, 240, 240, 241, 242, 242, 243,
     244, 244, 245, 246, 246, 247, 247, 248, 249, 249, 250, 251, 251, 252,
     253, 253, 254, 254, 255},

    {16, 23, 28, 32, 36, 39, 42, 45, 48, 50, 53, 55, 57, 60, 62, 64, 66, 68,
     69, 71, 73, 75, 76, 78, 80, 81, 83, 84, 86, 87, 89, 90, 92, 93, 94, 96,
     97, 98, 100, 101, 102, 103, 105, 106, 107, 108, 109, 110, 112, 113, 114,
     115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 128, 128,
     129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142,
     143, 143, 144, 145, 146, 147, 148, 149, 150, 150, 151, 152, 153, 154,
     155, 155, 156, 157, 158, 159, 159, 160, 161, 162, 163, 163, 164, 165,
     166, 166, 167, 168, 169, 169, 170, 171, 172, 172, 173, 174, 175, 175,
     176, 177, 177, 178, 179, 180, 180, 181, 182, 182, 183, 184, 184, 185,
     186, 187, 187, 188, 189, 189, 190, 191, 191, 192, 193, 193, 194, 195,
     195, 196, 196, 197, 198, 198, 199, 200, 200, 201, 202, 202, 203, 203,
     204, 205, 205, 206, 207, 207, 208, 208, 209, 210, 210, 211, 211, 212,
     213, 213, 214, 214, 215, 216, 216, 217, 217, 218, 219, 219, 220, 220,
     221, 221, 222, 223, 223, 224, 224, 225, 225, 226, 227, 227, 228, 228,
     229, 229, 230, 230, 231, 232, 232, 233, 233, 234, 234, 235, 235, 236,
     236, 237, 237, 238, 239, 239, 240, 240, 241, 241, 242, 242, 243, 243,
     244, 244, 245, 245, 246, 246, 247, 247, 248, 248, 249, 249, 250, 250,
     251, 251, 252, 252, 253, 254, 254, 255, 255}
};

//---------------------------------------------------------------------------
//
// PROC V_DrawPatch
//
// Draws a column based masked pic to the screen.
//
//---------------------------------------------------------------------------

void V_DrawPatch(int x, int y, patch_t * patch)
{
    int count;
    int col;
    column_t *column;
    byte *desttop;
    byte *dest;
    byte *source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);
    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0
        || y + SHORT(patch->height) > SCREENHEIGHT)
    {
        I_Error("Bad V_DrawPatch");
    }
    col = 0;
    desttop = screen + y * SCREENWIDTH + x;
    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++)
    {
        column = (column_t *) ((byte *) patch + LONG(patch->columnofs[col]));
        // Step through the posts in a column
        while (column->topdelta != 0xff)
        {
            source = (byte *) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;
            while (count--)
            {
                *dest = *source++;
                dest += SCREENWIDTH;
            }
            column = (column_t *) ((byte *) column + column->length + 4);
        }
    }
}

/*
==================
=
= V_DrawFuzzPatch
=
= Masks a column based translucent masked pic to the screen.
=
==================
*/
extern byte *tinttable;

void V_DrawFuzzPatch(int x, int y, patch_t * patch)
{
    int count, col;
    column_t *column;
    byte *desttop, *dest, *source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0
        || y + SHORT(patch->height) > SCREENHEIGHT)
        I_Error("Bad V_DrawPatch");

    col = 0;
    desttop = screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++)
    {
        column = (column_t *) ((byte *) patch + LONG(patch->columnofs[col]));

// step through the posts in a column

        while (column->topdelta != 0xff)
        {
            source = (byte *) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--)
            {
                *dest = tinttable[*dest + ((*source++) << 8)];
                dest += SCREENWIDTH;
            }
            column = (column_t *) ((byte *) column + column->length + 4);
        }
    }
}

/*
==================
=
= V_DrawAltFuzzPatch
=
= Masks a column based translucent masked pic to the screen.
=
==================
*/
extern byte *tinttable;

void V_DrawAltFuzzPatch(int x, int y, patch_t * patch)
{
    int count, col;
    column_t *column;
    byte *desttop, *dest, *source;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0
        || y + SHORT(patch->height) > SCREENHEIGHT)
    {
        I_Error("Bad V_DrawPatch");
    }

    col = 0;
    desttop = screen + y * SCREENWIDTH + x;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++)
    {
        column = (column_t *) ((byte *) patch + LONG(patch->columnofs[col]));

// step through the posts in a column

        while (column->topdelta != 0xff)
        {
            source = (byte *) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--)
            {
                *dest = tinttable[((*dest) << 8) + *source++];
                dest += SCREENWIDTH;
            }
            column = (column_t *) ((byte *) column + column->length + 4);
        }
    }
}

/*
==================
=
= V_DrawShadowedPatch
=
= Masks a column based masked pic to the screen.
=
==================
*/

void V_DrawShadowedPatch(int x, int y, patch_t * patch)
{
    int count, col;
    column_t *column;
    byte *desttop, *dest, *source;
    byte *desttop2, *dest2;
    int w;

    y -= SHORT(patch->topoffset);
    x -= SHORT(patch->leftoffset);

    if (x < 0 || x + SHORT(patch->width) > SCREENWIDTH || y < 0
        || y + SHORT(patch->height) > SCREENHEIGHT)
        I_Error("Bad V_DrawPatch");

    col = 0;
    desttop = screen + y * SCREENWIDTH + x;
    desttop2 = screen + (y + 2) * SCREENWIDTH + x + 2;

    w = SHORT(patch->width);
    for (; col < w; x++, col++, desttop++, desttop2++)
    {
        column = (column_t *) ((byte *) patch + LONG(patch->columnofs[col]));

// step through the posts in a column

        while (column->topdelta != 0xff)
        {
            source = (byte *) column + 3;
            dest = desttop + column->topdelta * SCREENWIDTH;
            dest2 = desttop2 + column->topdelta * SCREENWIDTH;
            count = column->length;

            while (count--)
            {
                *dest2 = tinttable[((*dest2) << 8)];
                dest2 += SCREENWIDTH;
                *dest = *source++;
                dest += SCREENWIDTH;

            }
            column = (column_t *) ((byte *) column + column->length + 4);
        }
    }
}

//---------------------------------------------------------------------------
//
// PROC V_DrawRawScreen
//
//---------------------------------------------------------------------------

void V_DrawRawScreen(byte * raw)
{
    memcpy(screen, raw, SCREENWIDTH * SCREENHEIGHT);
}

//---------------------------------------------------------------------------
//
// PROC V_Init
//
//---------------------------------------------------------------------------

void V_Init(void)
{
    // I_AllocLow will put screen in low dos memory on PCs.
    screen = I_AllocLow(SCREENWIDTH * SCREENHEIGHT);
}