Function BmpCopyBlock

xdevice.cpp:312–339

// another, stretching pixels as needed. Like the Windows StretchBlt() API.

void BmpCopyBlock(CONST Bitmap *bs, int x1, int y1, int x2, int y2,
  Bitmap *bd, int x3, int y3, int x4, int y4)
{
  int xs = x2-x1+1, ys = y2-y1+1, xd = x4-x3+1, yd = y4-y3+1,
    x, y, xT, yT, nR, nG, nB;
  byte *pbDst;

  // Sanity checks of coordinate bounds, which shouldn't ever fail.
  Assert(FBetween(x1, 0, bs->x-1));
  Assert(FBetween(y1, 0, bs->y-1));
  Assert(FBetween(x2, 0, bs->x-1));
  Assert(FBetween(y2, 0, bs->y-1));
  Assert(FBetween(x3, 0, bd->x-1));
  Assert(FBetween(y3, 0, bd->y-1));
  Assert(FBetween(x4, 0, bd->x-1));
  Assert(FBetween(y4, 0, bd->y-1));

  for (y = y3; y <= y4; y++) {
    pbDst = _PbXY(bd, x3, y);
    yT = y1 + (y-y3) * ys / yd;
    for (x = x3; x <= x4; x++) {
      xT = x1 + (x-x3) * xs / xd;
      _GetRGB(_PbXY(bs, xT, yT), &nR, &nG, &nB);
      _SetRGB(pbDst, nR, nG, nB);
      pbDst += cbPixelK;
    }
  }
}


// Adjust the color of a pixel on a world map, based on whether the location