public static Bitmap ToRGBA(VGABitmap vga)
{
var bmp = new Bitmap(vga.Width, vga.Height);
for (int y = 0; y < vga.Height; ++y)
{
for (int x = 0; x < vga.Width; ++x)
{
int k = vga.Data[x + y * vga.Width];
if (k != 0)
{
bmp.SetPixel(x, y, Color.FromArgb(Convert6BitTo8Bit(vga.Palette[k * 3]), Convert6BitTo8Bit(vga.Palette[k * 3 + 1]), Convert6BitTo8Bit(vga.Palette[k * 3 + 2])));
}
}
}
return(bmp);
}
public List <VGABitmap> DecodeFrames(BOBFile bob)
{
List <VGABitmap> frames = new List <VGABitmap>(bob.Frames.Count);
foreach (var frame in bob.Frames)
{
//System.IO.File.WriteAllBytes("dp.com", frame.DrawProgram);
var cpu = new DrawProgramCPU {
Text = frame.DrawProgram, Data = frame.PixelData
};
byte[] screenbuffer = new byte[frame.Width * frame.Height];
//byte[] dest = new byte[5000];
int page = -1;
// this number was determined by experimentation
// the draw-program appears to align lines of pixels along these boundaries
// might have something to do with how EGA works, or simply a kink of the game
int rowBytes = 86;
cpu.Write += (s, e) =>
{
//dest[e.Address] = (byte)e.Value;
int pageAddr = e.Address;
int x = (pageAddr % rowBytes) * 4;
int y = pageAddr / rowBytes;
switch (page)
{
case 0: break;
case 1: x -= 3; break;
case 2: x -= 6; break;
case 3: x -= 9; break;
default:
return;
}
if (x + y * frame.Width < screenbuffer.Length)
{
screenbuffer[x + y * frame.Width] = (byte)e.Value;
}
};
// the draw-program calls this at the beginning of every EGA page:
cpu.EgaSequencerReset += (s, e) =>
{
++page;
};
cpu.Call(0); // call the draw-program
var vgabmp = new VGABitmap(frame.Width, frame.Height, bob.Palette);
vgabmp.Data = screenbuffer;
frames.Add(vgabmp);
}
return(frames);
}
