GARbro-mirror/Legacy/System98/ImageG.cs
2023-10-20 18:21:55 +04:00

336 lines
10 KiB
C#

//! \file ImageG.cs
//! \date 2023 Oct 15
//! \brief System-98 engine image format (PC-98).
//
// Copyright (C) 2023 by morkt
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//
using GameRes.Utility;
using System;
using System.ComponentModel.Composition;
using System.IO;
using System.Windows.Media;
// [951216][Four-Nine] Lilith
namespace GameRes.Formats.System98
{
[Export(typeof(ImageFormat))]
public class GFormat : ImageFormat
{
public override string Tag => "G/SYSTEM98";
public override string Description => "System-98 engine image format";
public override uint Signature => 0;
public GFormat ()
{
Extensions = new[] { "g", "" };
}
public override ImageMetaData ReadMetaData (IBinaryStream file)
{
if (file.Length < 61)
return null;
var header = file.ReadHeader (0xA);
ushort width = Binary.BigEndian (header.ToUInt16 (6));
ushort height = Binary.BigEndian (header.ToUInt16 (8));
if (0 == width || 0 == height || (width & 7) != 0 || width > 640 || height > 400)
return null;
return new ImageMetaData {
Width = width,
Height = height,
BPP = 4,
};
}
public override ImageData Read (IBinaryStream file, ImageMetaData info)
{
file.Position = 0xA;
var palette = ReadPalette (file.AsStream, 16, PaletteFormat.Rgb);
var reader = new GraBaseReader (file, info);
reader.UnpackBits();
return ImageData.Create (info, PixelFormats.Indexed4, palette, reader.Pixels, reader.Stride);
}
public override void Write (Stream file, ImageData image)
{
throw new System.NotImplementedException ("GFormat.Write not implemented");
}
}
internal class GraBaseReader
{
protected IBinaryStream m_input;
protected ImageMetaData m_info;
protected int m_output_stride;
protected byte[] m_pixels;
public byte[] Pixels => m_pixels;
public int Stride => m_output_stride;
public GraBaseReader (IBinaryStream file, ImageMetaData info)
{
m_input = file;
m_info = info;
m_output_stride = m_info.iWidth >> 1;
m_pixels = new byte[m_output_stride * m_info.iHeight];
}
ushort[] m_buffer;
public void UnpackBits ()
{
try
{
UnpackBitsInternal();
}
catch (EndOfStreamException)
{
FlushBuffer();
}
}
void UnpackBitsInternal ()
{
int width = m_info.iWidth;
int wTimes2 = width << 1;
int wTimes4 = width << 2;
int buffer_size = wTimes4 + wTimes2;
m_buffer = new ushort[buffer_size >> 1];
m_dst = 0;
InitFrame();
InitBitReader();
ushort p = ReadPair (0);
for (int i = 0; i < width; ++i)
m_buffer[i] = p;
int dst = wTimes2;
int prev_src = 0;
while (m_dst < m_pixels.Length)
{
bool same_line = false;
int src = -width;
if (GetNextBit() != 0)
{
if (GetNextBit() == 0)
src <<= 1;
else if (GetNextBit() == 0)
src += 1;
else
src -= 1;
}
else if (GetNextBit() == 0)
{
src = -4;
p = m_buffer[dst/2-1];
if ((p & 0xFF) == (p >> 8))
same_line = src != prev_src;
}
if (src != prev_src)
{
prev_src = src;
if (!same_line)
src += dst;
else
src = dst - 2;
if (GetNextBit() != 0)
{
int bitlength = 0;
do
{
++bitlength;
}
while (GetNextBit() != 0);
int count = 1;
while (bitlength --> 0)
count = count << 1 | GetNextBit();
int remaining = (buffer_size - dst) >> 1;
while (count > remaining)
{
count -= remaining;
MovePixels (m_buffer, src, dst, remaining);
src += remaining << 1;
if (FlushBuffer())
return;
dst = wTimes2;
src -= wTimes4;
remaining = wTimes4 >> 1;
}
MovePixels (m_buffer, src, dst, count);
dst += count << 1;
if (dst == buffer_size)
{
if (FlushBuffer())
return;
dst = wTimes2;
}
}
else
{
MovePixels (m_buffer, src, dst, 1);
dst += 2;
if (dst == buffer_size)
{
if (FlushBuffer())
return;
dst = wTimes2;
}
}
}
else
{
p = m_buffer[dst/2-1];
do
{
byte prev = (byte)(p >> 8);
p = ReadPair (prev);
m_buffer[dst >> 1] = p;
dst += 2;
if (dst == buffer_size)
{
if (FlushBuffer())
return;
dst = wTimes2;
}
}
while (GetNextBit() != 0);
prev_src = 0;
}
}
}
int m_dst;
bool FlushBuffer ()
{
MovePixels (m_buffer, m_info.iWidth * 4, 0, m_info.iWidth);
int src = m_info.iWidth;
int count = Math.Min (m_info.iWidth << 1, m_pixels.Length - m_dst);
while (count --> 0)
{
ushort p = m_buffer[src++];
m_pixels[m_dst++] = (byte)((p & 0xF0) | p >> 12);
}
return m_dst == m_pixels.Length;
}
ushort ReadPair (int pos)
{
byte al = ReadPixel (pos);
byte ah = ReadPixel (al);
return (ushort)(al | ah << 8);
}
byte ReadPixel (int pos)
{
byte px = 0;
if (GetNextBit() == 0)
{
int count = 1;
if (GetNextBit() != 0)
{
if (GetNextBit() != 0)
{
count = count << 1 | GetNextBit();
}
count = count << 1 | GetNextBit();
}
count = count << 1 | GetNextBit();
pos += count;
px = m_frame[pos--];
while (count --> 0)
{
m_frame[pos+1] = m_frame[pos];
--pos;
}
m_frame[pos+1] = px;
}
else if (GetNextBit() == 0)
{
px = m_frame[pos];
}
else
{
px = m_frame[pos+1];
m_frame[pos+1] = m_frame[pos];
m_frame[pos] = px;
}
return px;
}
byte[] m_frame;
void InitFrame ()
{
m_frame = new byte[0x100];
int p = 0;
byte a = 0;
for (int j = 0; j < 0x10; ++j)
{
for (int i = 0; i < 0x10; ++i)
{
m_frame[p++] = a;
a -= 0x10;
}
a += 0x10;
}
}
void MovePixels (ushort[] pixels, int src, int dst, int count)
{
count <<= 1;
if (dst > src)
{
while (count > 0)
{
int preceding = Math.Min (dst - src, count);
Buffer.BlockCopy (pixels, src, pixels, dst, preceding);
dst += preceding;
count -= preceding;
}
}
else
{
Buffer.BlockCopy (pixels, src, pixels, dst, count);
}
}
int m_bits;
int m_bit_count;
void InitBitReader ()
{
m_bit_count = 1;
}
byte GetNextBit ()
{
if (--m_bit_count <= 0)
{
m_bits = m_input.ReadUInt8();
m_bit_count = 8;
}
int bit = (m_bits >> 7) & 1;
m_bits <<= 1;
return (byte)bit;
}
}
}