unsafe void DrawBG(int *pal)
{
int bgheight = vdp.FrameHeight == 192 ? 224 : 256;
int maxtile = bgheight * 4;
if (bgheight != bmpViewBG.bmp.Height)
{
bmpViewBG.Height = bgheight;
bmpViewBG.ChangeBitmapSize(256, bgheight);
}
var lockdata = bmpViewBG.bmp.LockBits(new Rectangle(0, 0, 256, bgheight), ImageLockMode.WriteOnly, PixelFormat.Format32bppArgb);
int *dest = (int *)lockdata.Scan0;
int pitch = lockdata.Stride / sizeof(int);
fixed(byte *src = vdp.PatternBuffer)
fixed(byte *vram = vdp.VRAM)
{
short *map = (short *)(vram + vdp.CalcNameTableBase());
for (int tile = 0; tile < maxtile; tile++)
{
short bgent = *map++;
bool hflip = (bgent & 1 << 9) != 0;
bool vflip = (bgent & 1 << 10) != 0;
int * tpal = pal + ((bgent & 1 << 11) >> 7);
int srcaddr = (bgent & 511) * 64;
int tx = tile & 31;
int ty = tile >> 5;
int destaddr = ty * 8 * pitch + tx * 8;
Draw8x8hv(src + srcaddr, dest + destaddr, pitch, tpal, hflip, vflip);
}
}
bmpViewBG.bmp.UnlockBits(lockdata);
bmpViewBG.Refresh();
}
