public LP[] cvs; // conversion matrix
public CTABLE Clone()
{
CTABLE ret = new CTABLE();
ret.id = id;
ret.ll = ll;
ret.del = del;
ret.lim = lim;
ret.cvs = cvs;
return(ret);
}
//**********************************************************************
// pj_gridinfo_init_ntv2()
//
// Load a ntv2 (.gsb) file.
//**********************************************************************
static bool pj_gridinfo_init_ntv2(projCtx ctx, FileStream fid, PJ_GRIDINFO gilist)
{
byte[] header=new byte[11*16];
// --------------------------------------------------------------------
// Read the overview header.
// --------------------------------------------------------------------
try
{
if(fid.Read(header, 0, header.Length)!=header.Length)
{
header=null;
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
}
catch
{
header=null;
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
// --------------------------------------------------------------------
// Byte swap interesting fields if needed.
// --------------------------------------------------------------------
if(!IS_LSB)
{
swap_words(header, 8, 4, 1);
swap_words(header, 8+16, 4, 1);
swap_words(header, 8+32, 4, 1);
swap_words(header, 8+7*16, 8, 1);
swap_words(header, 8+8*16, 8, 1);
swap_words(header, 8+9*16, 8, 1);
swap_words(header, 8+10*16, 8, 1);
}
// --------------------------------------------------------------------
// Get the subfile count out ... all we really use for now.
// --------------------------------------------------------------------
int num_subfiles=BitConverter.ToInt32(header, 8+32);
// ====================================================================
// Step through the subfiles, creating a PJ_GRIDINFO for each.
// ====================================================================
for(int subfile=0; subfile<num_subfiles; subfile++)
{
// --------------------------------------------------------------------
// Read header.
// --------------------------------------------------------------------
try
{
if(fid.Read(header, 0, header.Length)!=header.Length)
{
header=null;
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
}
catch
{
header=null;
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
if(Encoding.ASCII.GetString(header, 0, 8).StartsWith("SUB_NAME"))
{
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
// --------------------------------------------------------------------
// Byte swap interesting fields if needed.
// --------------------------------------------------------------------
if(!IS_LSB)
{
swap_words(header, 8+16*4, 8, 1);
swap_words(header, 8+16*5, 8, 1);
swap_words(header, 8+16*6, 8, 1);
swap_words(header, 8+16*7, 8, 1);
swap_words(header, +8+16*8, 8, 1);
swap_words(header, 8+16*9, 8, 1);
swap_words(header, 8+16*10, 4, 1);
}
// --------------------------------------------------------------------
// Initialize a corresponding "ct" structure.
// --------------------------------------------------------------------
CTABLE ct=new CTABLE();
ct.id=Encoding.ASCII.GetString(header, 8, 8);
ct.ll.lam=-BitConverter.ToDouble(header, 7*16+8); // W_LONG
ct.ll.phi=BitConverter.ToDouble(header, 4*16+8); // S_LAT
LP ur;
ur.lam=-BitConverter.ToDouble(header, 6*16+8); // E_LONG
ur.phi=BitConverter.ToDouble(header, 5*16+8); // N_LAT
ct.del.lam=BitConverter.ToDouble(header, 9*16+8);
ct.del.phi=BitConverter.ToDouble(header, 8*16+8);
ct.lim.lam=(int)(Math.Abs(ur.lam-ct.ll.lam)/ct.del.lam+0.5)+1;
ct.lim.phi=(int)(Math.Abs(ur.phi-ct.ll.phi)/ct.del.phi+0.5)+1;
#if DEBUG
Console.Error.WriteLine("NTv2 {0} {1}x{2}: LL=({3},{4}) UR=({5},{6})", ct.id,
ct.lim.lam, ct.lim.phi, ct.ll.lam/3600.0, ct.ll.phi/3600.0, ur.lam/3600.0, ur.phi/3600.0);
#endif
ct.ll.lam*=Proj.DEG_TO_RAD/3600.0;
ct.ll.phi*=Proj.DEG_TO_RAD/3600.0;
ct.del.lam*=Proj.DEG_TO_RAD/3600.0;
ct.del.phi*=Proj.DEG_TO_RAD/3600.0;
int gs_count=BitConverter.ToInt32(header, 8+16*10);
if(gs_count!=ct.lim.lam*ct.lim.phi)
{
Console.Error.WriteLine("GS_COUNT({0}) does not match expected cells ({1}x{2}={3})",
gs_count, ct.lim.lam, ct.lim.phi, ct.lim.lam*ct.lim.phi);
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
ct.cvs=null;
PJ_GRIDINFO gi;
// --------------------------------------------------------------------
// Create a new gridinfo for this if we aren't processing the
// 1st subfile, and initialize our grid info.
// --------------------------------------------------------------------
if(subfile==0) gi=gilist;
else
{
gi=new PJ_GRIDINFO();
gi.gridname=gilist.gridname;
gi.filename=gilist.filename;
gi.next=null;
}
gi.ct=ct;
gi.format="ntv2";
gi.grid_offset=fid.Position;
// --------------------------------------------------------------------
// Attach to the correct list or sublist.
// --------------------------------------------------------------------
if(Encoding.ASCII.GetString(header, 24, 4)=="NONE")
{
if(gi!=gilist)
{
PJ_GRIDINFO lnk=gilist;
while(lnk.next!=null) lnk=lnk.next;
lnk.next=gi;
}
}
else
{
PJ_GRIDINFO gp=pj_gridinfo_parent(gilist, Encoding.ASCII.GetString(header, 24, 8));
if(gp==null)
{
#if DEBUG
Console.Error.WriteLine("pj_gridinfo_init_ntv2(): failed to find parent {0} for {1}.",
Encoding.ASCII.GetString(header, 24, 8), gi.ct.id);
#endif
PJ_GRIDINFO lnk=gilist;
while(lnk.next!=null) lnk=lnk.next;
lnk.next=gi;
}
else if(gp.child==null) gp.child=gi;
else
{
PJ_GRIDINFO lnk=gp.child;
while(lnk.next!=null) lnk=lnk.next;
lnk.next=gi;
}
}
// --------------------------------------------------------------------
// Seek past the data.
// --------------------------------------------------------------------
fid.Seek(gs_count*16, SeekOrigin.Current);
}
return true;
}
//**********************************************************************
// pj_gridinfo_init_ntv1()
//
// Load an NTv1 style Canadian grid shift file.
//**********************************************************************
static bool pj_gridinfo_init_ntv1(projCtx ctx, FileStream fid, PJ_GRIDINFO gi)
{
byte[] header=new byte[176];
// --------------------------------------------------------------------
// Read the header.
// --------------------------------------------------------------------
try
{
if(fid.Read(header, 0, header.Length)!=header.Length)
{
header=null;
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
}
catch
{
header=null;
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
// --------------------------------------------------------------------
// Regularize fields of interest.
// --------------------------------------------------------------------
if(IS_LSB)
{
swap_words(header, 8, 4, 1);
swap_words(header, 24, 8, 1);
swap_words(header, 40, 8, 1);
swap_words(header, 56, 8, 1);
swap_words(header, 72, 8, 1);
swap_words(header, 88, 8, 1);
swap_words(header, 104, 8, 1);
}
if(BitConverter.ToInt32(header, 8)!=12)
{
Console.Error.WriteLine("NTv1 grid shift file has wrong record count, corrupt?");
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
// --------------------------------------------------------------------
// Fill in CTABLE structure.
// --------------------------------------------------------------------
CTABLE ct=new CTABLE();
ct.id="NTv1 Grid Shift File";
ct.ll.lam=-BitConverter.ToDouble(header, 72);
ct.ll.phi=BitConverter.ToDouble(header, 24);
LP ur;
ur.lam=-BitConverter.ToDouble(header, 56);
ur.phi=BitConverter.ToDouble(header, 40);
ct.del.lam=BitConverter.ToDouble(header, 104);
ct.del.phi=BitConverter.ToDouble(header, 88);
ct.lim.lam=(int)(Math.Abs(ur.lam-ct.ll.lam)/ct.del.lam+0.5)+1;
ct.lim.phi=(int)(Math.Abs(ur.phi-ct.ll.phi)/ct.del.phi+0.5)+1;
#if DEBUG
Console.Error.WriteLine("NTv1 {0}x{1}: LL=({2},{3}) UR=({4},{5})",
ct.lim.lam, ct.lim.phi, ct.ll.lam, ct.ll.phi, ur.lam, ur.phi);
#endif
ct.ll.lam*=Proj.DEG_TO_RAD;
ct.ll.phi*=Proj.DEG_TO_RAD;
ct.del.lam*=Proj.DEG_TO_RAD;
ct.del.phi*=Proj.DEG_TO_RAD;
ct.cvs=null;
gi.ct=ct;
gi.grid_offset=fid.Position;
gi.format="ntv1";
return true;
}
//**********************************************************************
// pj_gridinfo_init_gtx()
//
// Load a NOAA .gtx vertical datum shift file.
//**********************************************************************
static bool pj_gridinfo_init_gtx(projCtx ctx, FileStream fid, PJ_GRIDINFO gi)
{
byte[] header=new byte[40];
CTABLE ct;
double xorigin, yorigin, xstep, ystep;
int rows, columns;
// --------------------------------------------------------------------
// Read the header.
// --------------------------------------------------------------------
if(fid.Read(header, 0, 40)!=40)
{
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
// --------------------------------------------------------------------
// Regularize fields of interest and extract.
// --------------------------------------------------------------------
if(IS_LSB)
{
swap_words(header, 0, 8, 4);
swap_words(header, 32, 4, 2);
}
yorigin=BitConverter.ToDouble(header, 0);
xorigin=BitConverter.ToDouble(header, 8);
ystep=BitConverter.ToDouble(header, 16);
xstep=BitConverter.ToDouble(header, 24);
rows=BitConverter.ToInt32(header, 32);
columns=BitConverter.ToInt32(header, 36);
if(xorigin<-360||xorigin>360
||yorigin<-90||yorigin>90)
{
Console.WriteLine("gtx file header has invalid extents, corrupt?");
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
// --------------------------------------------------------------------
// Fill in CTABLE structure.
// --------------------------------------------------------------------
ct=new CTABLE();
ct.id="GTX Vertical Grid Shift File";
ct.ll.lam=xorigin;
ct.ll.phi=yorigin;
ct.del.lam=xstep;
ct.del.phi=ystep;
ct.lim.lam=columns;
ct.lim.phi=rows;
// some GTX files come in 0-360 and we shift them back into the
// expected -180 to 180 range if possible. This does not solve
// problems with grids spanning the dateline.
if(ct.ll.lam>=180.0) ct.ll.lam-=360.0;
#if !DEBUG
if(ct.ll.lam>=0.0&&ct.ll.lam+ct.del.lam*ct.lim.lam>180.0)
Console.Error.WriteLine("This GTX spans the dateline! This will cause problems.");
Console.Error.WriteLine("GTX {0}x{1}: LL=({2},{3}) UR=({4},{5})", ct.lim.lam, ct.lim.phi, ct.ll.lam, ct.ll.phi, ct.ll.lam+(columns-1)*xstep, ct.ll.phi+(rows-1)*ystep);
#endif
ct.ll.lam*=Proj.DEG_TO_RAD;
ct.ll.phi*=Proj.DEG_TO_RAD;
ct.del.lam*=Proj.DEG_TO_RAD;
ct.del.phi*=Proj.DEG_TO_RAD;
ct.cvs=null;
gi.ct=ct;
gi.grid_offset=40;
gi.format="gtx";
return true;
}
//**********************************************************************
// nad_ctable2_init()
//
// Read the header portion of a "ctable2" format grid.
//**********************************************************************
public static CTABLE nad_ctable2_init(projCtx ctx, Stream fid)
{
try
{
CTABLE ct=new CTABLE();
byte[] header=new byte[160];
// read the table header
fid.Read(header, 0, 160);
if(!IS_LSB)
{
swap_words(header, 96, 8, 4);
swap_words(header, 128, 4, 2);
}
MemoryStream mem=new MemoryStream(header);
BinaryReader br=new BinaryReader(mem);
byte[] signature=new byte[16];
byte[] tmpID=new byte[80];
signature=br.ReadBytes(16);
string sig=Encoding.ASCII.GetString(signature);
if(sig.Substring(0, 9)!="CTABLE V2")
{
Proj.pj_log(ctx, PJ_LOG.ERROR, "ctable2 - wrong header!");
Proj.pj_ctx_set_errno(ctx, -38);
return null;
}
// read the table header
tmpID=br.ReadBytes(80);
ct.ll.lam=br.ReadDouble();
ct.ll.phi=br.ReadDouble();
ct.del.lam=br.ReadDouble();
ct.del.phi=br.ReadDouble();
ct.lim.lam=br.ReadInt32();
ct.lim.phi=br.ReadInt32();
// do some minimal validation to ensure the structure isn't corrupt
if(ct.lim.lam<1||ct.lim.lam>100000||ct.lim.phi<1||ct.lim.phi>100000)
{
Proj.pj_ctx_set_errno(ctx, -38);
return null;
}
ct.id=Encoding.ASCII.GetString(tmpID);
ct.id=ct.id.Trim(); // trim white space and newlines off id
ct.cvs=null;
return ct;
}
catch
{
Proj.pj_ctx_set_errno(ctx, -38);
return null;
}
}
//**********************************************************************
// nad_free()
//
// Free a CTABLE grid shift structure produced by nad_init().
//**********************************************************************
public static void nad_free(CTABLE ct)
{
if(ct!=null) ct.cvs=null;
}
//**********************************************************************
// nad_ctable_load()
//
// Load the data portion of a ctable formatted grid.
//**********************************************************************
public static bool nad_ctable_load(projCtx ctx, CTABLE ct, Stream fid)
{
try
{
fid.Seek(80+16+16+8+4, SeekOrigin.Begin); // 80+16+16+8+4 ?= sizeof(struct CTABLE)
// read all the actual shift values
int a_size=ct.lim.lam*ct.lim.phi;
ct.cvs=new LP[a_size];
BinaryReader br=new BinaryReader(fid);
for(int i=0; i<a_size; i++)
{
ct.cvs[i].lam=br.ReadSingle();
ct.cvs[i].phi=br.ReadSingle();
}
}
catch
{
ct.cvs=null;
#if DEBUG
Console.Error.WriteLine("ctable loading failed on fread() - binary incompatible?");
#endif
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
return true;
}
//**********************************************************************
// nad_ctable_init()
//
// Read the header portion of a "ctable" format grid.
//**********************************************************************
public static CTABLE nad_ctable_init(projCtx ctx, Stream fid)
{
try
{
CTABLE ct=new CTABLE();
byte[] tmpID=new byte[80];
// read the table header
fid.Read(tmpID, 0, 80);
BinaryReader br=new BinaryReader(fid);
ct.ll.lam=br.ReadDouble();
ct.ll.phi=br.ReadDouble();
ct.del.lam=br.ReadDouble();
ct.del.phi=br.ReadDouble();
ct.lim.lam=br.ReadInt32();
ct.lim.phi=br.ReadInt32();
br.ReadInt32(); // FLP* cvs
// do some minimal validation to ensure the structure isn't corrupt
if(ct.lim.lam<1||ct.lim.lam>100000||ct.lim.phi<1||ct.lim.phi>100000)
{
Proj.pj_ctx_set_errno(ctx, -38);
return null;
}
ct.id=Encoding.ASCII.GetString(tmpID);
ct.id=ct.id.Trim(); // trim white space and newlines off id
ct.cvs=null;
return ct;
}
catch
{
Proj.pj_ctx_set_errno(ctx, -38);
return null;
}
}
//**********************************************************************
// nad_ctable2_load()
//
// Load the data portion of a ctable2 formatted grid.
//**********************************************************************
public static bool nad_ctable2_load(projCtx ctx, CTABLE ct, Stream fid)
{
try
{
fid.Seek(160, SeekOrigin.Begin);
// read all the actual shift values
int a_size=ct.lim.lam*ct.lim.phi;
ct.cvs=new LP[a_size];
BinaryReader br=new BinaryReader(fid);
if(IS_LSB)
{
for(int i=0; i<a_size; i++)
{
ct.cvs[i].lam=br.ReadSingle();
ct.cvs[i].phi=br.ReadSingle();
}
}
else
{
byte[] buf=br.ReadBytes(a_size*8);
swap_words(buf, 0, 4, a_size*2);
using(BinaryReader br2=new BinaryReader(new MemoryStream(buf)))
{
for(int i=0; i<a_size; i++)
{
ct.cvs[i].lam=br2.ReadSingle();
ct.cvs[i].phi=br2.ReadSingle();
}
}
}
return true;
}
catch
{
ct.cvs=null;
#if DEBUG
Proj.pj_log(ctx, PJ_LOG.ERROR, "ctable2 loading failed on fread() - binary incompatible?");
#endif
Proj.pj_ctx_set_errno(ctx, -38);
return false;
}
}
public static LP nad_cvt(LP @in, bool inverse, CTABLE ct)
{
const int MAX_TRY=9;
if(@in.lam==Libc.HUGE_VAL) return @in;
// normalize input to ll origin
LP tb=@in;
tb.lam-=ct.ll.lam;
tb.phi-=ct.ll.phi;
tb.lam=Proj.adjlon(tb.lam-Proj.PI)+Proj.PI;
LP t=nad_intr(tb, ct);
if(inverse)
{
LP del, dif;
int i=MAX_TRY;
if(t.lam==Libc.HUGE_VAL) return t;
t.lam=tb.lam+t.lam;
t.phi=tb.phi-t.phi;
do
{
del=nad_intr(t, ct);
// This case used to return failure, but I have
// changed it to return the first order approximation
// of the inverse shift. This avoids cases where the
// grid shift *into* this grid came from another grid.
// While we aren't returning optimally correct results
// I feel a close result in this case is better than
// no result. NFW
// To demonstrate use -112.5839956 49.4914451 against
// the NTv2 grid shift file from Canada.
if(del.lam==Libc.HUGE_VAL)
{
#if DEBUG
Console.Error.WriteLine("Inverse grid shift iteration failed, presumably at grid edge.\nUsing first approximation.");
#endif
break;
}
t.lam-=dif.lam=t.lam-del.lam-tb.lam;
t.phi-=dif.phi=t.phi+del.phi-tb.phi;
} while((i--)!=0&&Math.Abs(dif.lam)>TOL12&&Math.Abs(dif.phi)>TOL12);
if(i<0)
{
#if DEBUG
Console.Error.WriteLine("Inverse grid shift iterator failed to converge.");
#endif
t.lam=t.phi=Libc.HUGE_VAL;
return t;
}
@in.lam=Proj.adjlon(t.lam+ct.ll.lam);
@in.phi=t.phi+ct.ll.phi;
}
else
{
if(t.lam==Libc.HUGE_VAL) @in=t;
else
{
@in.lam-=t.lam;
@in.phi+=t.phi;
}
}
return @in;
}
// Determine nad table correction value
public static LP nad_intr(LP t, CTABLE ct)
{
LP val, frct;
ILP indx;
double m00, m10, m01, m11;
int f00, f10, f01, f11;
int index;
int @in;
t.lam/=ct.del.lam;
t.phi/=ct.del.phi;
indx.lam=(int)Math.Floor(t.lam);
indx.phi=(int)Math.Floor(t.phi);
frct.lam=t.lam-indx.lam;
frct.phi=t.phi-indx.phi;
val.lam=val.phi=Libc.HUGE_VAL;
if(indx.lam<0)
{
if(indx.lam==-1&&frct.lam>0.99999999999)
{
indx.lam++;
frct.lam=0.0;
}
else return val;
}
else
{
@in=indx.lam+1;
if(@in>=ct.lim.lam)
{
if(@in==ct.lim.lam&&frct.lam<1e-11)
{
indx.lam--;
frct.lam=1.0;
}
else return val;
}
}
if(indx.phi<0)
{
if(indx.phi==-1&&frct.phi>0.99999999999)
{
indx.phi++;
frct.phi=0.0;
}
else return val;
}
else
{
@in=indx.phi+1;
if(@in>=ct.lim.phi)
{
if(@in==ct.lim.phi&&frct.phi<1e-11)
{
indx.phi--;
frct.phi=1.0;
}
else return val;
}
}
index=indx.phi*ct.lim.lam+indx.lam;
f00=index++;
f10=index;
index+=ct.lim.lam;
f11=index--;
f01=index;
m11=m10=frct.lam;
m00=m01=1.0-frct.lam;
m11*=frct.phi;
m01*=frct.phi;
frct.phi=1.0-frct.phi;
m00*=frct.phi;
m10*=frct.phi;
val.lam=m00*ct.cvs[f00].lam+m10*ct.cvs[f10].lam+m01*ct.cvs[f01].lam+m11*ct.cvs[f11].lam;
val.phi=m00*ct.cvs[f00].phi+m10*ct.cvs[f10].phi+m01*ct.cvs[f01].phi+m11*ct.cvs[f11].phi;
return val;
}
