begin

        X:= X + dX;

        Y:= Y + dY;

        tx:= round(X);

        ty:= round(Y);

        if ((ty and $FFFFFC00) = 0) and ((tx and $FFFFF800) = 0)and (Land[ty, tx] <> 0) then

        case LandSurface.format.BytesPerPixel of

             1: ;

             2: PWord(p + LandSurface.pitch * ty + tx * 2)^:= cExplosionBorderColor;

             3: begin

                PByte(p + LandSurface.pitch * ty + tx * 3 + 0)^:= cExplosionBorderColor and $FF;

                PByte(p + LandSurface.pitch * ty + tx * 3 + 1)^:= (cExplosionBorderColor shr 8) and $FF;

                PByte(p + LandSurface.pitch * ty + tx * 3 + 2)^:= (cExplosionBorderColor shr 16);

                end;

             4: PLongword(p + LandSurface.pitch * ty + tx * 4)^:= cExplosionBorderColor;

             end

	end;