//----------------------------------------------
// SECTION 3: BIT MAP SECTION (BMS)
//----------------------------------------------
bool GribV1Record::readGribSection3_BMS(ZUFILE* file) {
fileOffset3 = zu_tell(file);
if (! hasBMS) {
sectionSize3 = 0;
return ok;
}
sectionSize3 = readInt3(file);
(void) readChar(file);
int bitMapFollows = readInt2(file);
if (bitMapFollows != 0) {
return ok;
}
BMSbits = new zuchar[sectionSize3-6];
if (!BMSbits) {
//erreur("Record: out of memory");
ok = false;
}
for (zuint i=0; i<sectionSize3-6; i++) {
BMSbits[i] = readChar(file);
}
return ok;
}
static bool patchApplyIPS(const char *patchname, u8 **r, int *s)
{
// from the IPS spec at http://zerosoft.zophar.net/ips.htm
FILE *f = fopen(patchname, "rb");
if(!f)
return false;
bool result = false;
u8 *rom = *r;
int size = *s;
if(fgetc(f) == 'P' &&
fgetc(f) == 'A' &&
fgetc(f) == 'T' &&
fgetc(f) == 'C' &&
fgetc(f) == 'H') {
int b;
int offset;
int len;
result = true;
for(;;) {
// read offset
offset = readInt3(f);
// if offset == EOF, end of patch
if(offset == 0x454f46 || offset == -1)
break;
// read length
len = readInt2(f);
if(!len) {
// len == 0, RLE block
len = readInt2(f);
// byte to fill
int c = fgetc(f);
if(c == -1)
break;
b = (u8)c;
} else
b= -1;
// check if we need to reallocate our ROM
if((offset + len) >= size) {
size *= 2;
rom = (u8 *)realloc(rom, size);
*r = rom;
*s = size;
}
if(b == -1) {
// normal block, just read the data
if(fread(&rom[offset], 1, len, f) != (size_t)len)
break;
} else {
// fill the region with the given byte
while(len--) {
rom[offset++] = b;
}
}
}
}
// close the file
fclose(f);
return result;
}
//----------------------------------------------
// SECTION 4: BINARY DATA SECTION (BDS)
//----------------------------------------------
bool GribV1Record::readGribSection4_BDS(ZUFILE* file) {
fileOffset4 = zu_tell(file);
sectionSize4 = readInt3(file); // byte 1-2-3
zuchar flags = readChar(file); // byte 4
scaleFactorE = readSignedInt2(file); // byte 5-6
refValue = readFloat4(file); // byte 7-8-9-10
nbBitsInPack = readChar(file); // byte 11
scaleFactorEpow2 = pow(2.0,scaleFactorE);
unusedBitsEndBDS = flags & 0x0F;
isGridData = (flags&0x80) ==0;
isSimplePacking = (flags&0x80) ==0;
isFloatValues = (flags&0x80) ==0;
//printf("BDS type=%3d - bits=%02d - level %3d - %d\n", dataType, nbBitsInPack, levelType,levelValue);
if (! isGridData) {
//erreur("Record: need grid data");
ok = false;
}
if (! isSimplePacking) {
//erreur("Record: need simple packing");
ok = false;
}
if (! isFloatValues) {
//erreur("Record: need double values");
ok = false;
}
if (!ok) {
return ok;
}
// Allocate memory for the data
data = new float[Ni*Nj];
if (!data) {
//erreur("Record: out of memory");
ok = false;
}
zuint startbit = 0;
int datasize = sectionSize4-11;
zuchar *buf = new zuchar[datasize+4]; // +4 pour simplifier les decalages ds readPackedBits
if (!buf) {
//erreur("Record: out of memory");
ok = false;
}
if (zu_read(file, buf, datasize) != datasize) {
//erreur("Record: data read error");
ok = false;
eof = true;
}
if (!ok) {
return ok;
}
// Initialize the las 4 bytes of buf since we didn't read them
buf[datasize+0] = buf[datasize+1] = buf[datasize+2] = buf[datasize+3] = 0;
// Read data in the order given by isAdjacentI
zuint i, j, x;
int ind;
if (isAdjacentI) {
for (j=0; j<Nj; j++) {
for (i=0; i<Ni; i++) {
if (!hasDiDj && !isScanJpositive) {
ind = (Nj-1 -j)*Ni+i;
}
else {
ind = j*Ni+i;
}
if (hasValue(i,j)) {
x = readPackedBits(buf, startbit, nbBitsInPack);
data[ind] = (refValue + x*scaleFactorEpow2)/decimalFactorD;
startbit += nbBitsInPack;
}
else {
data[ind] = (float) GRIB_NOTDEF;
}
}
}
}
else {
for (i=0; i<Ni; i++) {
for (j=0; j<Nj; j++) {
if (!hasDiDj && !isScanJpositive) {
ind = (Nj-1 -j)*Ni+i;
}
else {
ind = j*Ni+i;
}
if (hasValue(i,j)) {
x = readPackedBits(buf, startbit, nbBitsInPack);
startbit += nbBitsInPack;
data[ind] = (refValue + x*scaleFactorEpow2)/decimalFactorD;
}
else {
data[ind] = (float)GRIB_NOTDEF;
}
}
}
}
if (buf) {
delete [] buf;
buf = NULL;
}
return ok;
}
//----------------------------------------------
// SECTION 2: THE GRID DESCRIPTION SECTION (GDS)
//----------------------------------------------
bool GribV1Record::readGribSection2_GDS(ZUFILE* file) {
if (! hasGDS)
return 0;
fileOffset2 = zu_tell(file);
sectionSize2 = readInt3(file); // byte 1-2-3
readChar(file); // byte 4 => NV
readChar(file); // byte 5 => PV
gridType = readChar(file); // byte 6
if (gridType != 0) {
erreur("Record: unknown grid type GDS(6) : %d",gridType);
ok = false;
}
Ni = readInt2(file); // byte 7-8
Nj = readInt2(file); // byte 9-10
La1 = readSignedInt3(file)/1000.0; // byte 11-12-13
Lo1 = readSignedInt3(file)/1000.0; // byte 14-15-16
resolFlags = readChar(file); // byte 17
La2 = readSignedInt3(file)/1000.0; // byte 18-19-20
Lo2 = readSignedInt3(file)/1000.0; // byte 21-22-23
if (Lo1>=0 && Lo1<=180 && Lo2<0) {
Lo2 += 360.0; // cross the 180 deg meridien,beetwen alaska and russia
}
Di = readSignedInt2(file)/1000.0; // byte 24-25
Dj = readSignedInt2(file)/1000.0; // byte 26-27
while ( Lo1> Lo2 && Di >0) { // horizontal size > 360 °
Lo1 -= 360.0;
}
double val=Lo2+Di;
while(val>=360) val-=360;
if(val==Lo1)
isFull=true;
hasDiDj =(resolFlags&0x80) !=0;
scanFlags = readChar(file); // byte 28
isScanIpositive = (scanFlags&0x80) ==0;
isScanJpositive = (scanFlags&0x40) !=0;
isAdjacentI = (scanFlags&0x20) ==0;
if (Lo2 > Lo1) {
lonMin = Lo1;
lonMax = Lo2;
}
else {
lonMin = Lo2;
lonMax = Lo1;
}
if (La2 > La1) {
latMin = La1;
latMax = La2;
}
else {
latMin = La2;
latMax = La1;
}
if (Ni<=1 || Nj<=1) {
erreur("Recordd: Ni=%u Nj=%u",Ni,Nj);
ok = false;
}
else {
Di = (Lo2-Lo1) / (Ni-1);
Dj = (La2-La1) / (Nj-1);
}
if (false) {
printf("====\n");
printf("Lo1=%f Lo2=%f La1=%f La2=%f\n", Lo1,Lo2,La1,La2);
printf("Ni=%u Nj=%u\n", Ni,Nj);
printf("hasDiDj=%d Di,Dj=(%f %f)\n", hasDiDj, Di,Dj);
printf("hasBMS=%d\n", hasBMS);
printf("isScanIpositive=%d isScanJpositive=%d isAdjacentI=%d\n",
isScanIpositive,isScanJpositive,isAdjacentI );
}
return ok;
}
//==============================================================
// Lecture des donnees
//==============================================================
//----------------------------------------------
// SECTION 0: THE INDICATOR SECTION (IS)
//----------------------------------------------
bool GribV1Record::readGribSection0_IS(ZUFILE* file) {
char strgrib[4];
memset (strgrib, 0, sizeof (strgrib));
zuint initFoffset;
fileOffset0 = zu_tell(file);
initFoffset=fileOffset0;
#if 1
char buf[1];
memset (buf, 0, sizeof (buf));
while(true)
{
if(zu_read(file,buf,1)!=1) break;
++fileOffset0;
if(buf[0]!='G')
continue;
if(zu_read(file,buf,1)!=1) break;
++fileOffset0;
if(buf[0]!='R')
{
if(buf[0]=='G')
zu_seek(file,--fileOffset0,SEEK_SET);
continue;
}
if(zu_read(file,buf,1)!=1) break;
++fileOffset0;
if(buf[0]!='I')
{
if(buf[0]=='G')
zu_seek(file,--fileOffset0,SEEK_SET);
continue;
}
if(zu_read(file,buf,1)!=1) break;
++fileOffset0;
if(buf[0]!='B')
{
if(buf[0]=='G')
zu_seek(file,--fileOffset0,SEEK_SET);
continue;
}
strgrib[0]='G';
strgrib[1]='R';
strgrib[2]='I';
strgrib[3]='B';
break;
}
#else
while((zu_read(file, strgrib, 4) == 4) &&
(strgrib[0] != 'G' || strgrib[1] != 'R' ||
strgrib[2] != 'I' || strgrib[3] != 'B')) {
zu_seek(file,++fileOffset0,SEEK_SET);
}
#endif
if(strgrib[0] != 'G' || strgrib[1] != 'R' ||
strgrib[2] != 'I' || strgrib[3] != 'B') {
if((fileOffset0-10)>initFoffset) // displaying error msg only if we are really far from initial offset
qWarning() << "Can't find next record / EOF - offset=" << fileOffset0 << ", initOffset=" << initFoffset ;
ok = false;
eof = true;
return false;
}
seekStart=zu_tell(file)-4;
totalSize = readInt3(file);
//qWarning() << "Start = " << seekStart << ", size = " << totalSize;
editionNumber = readChar(file);
if (editionNumber != 1) {
ok = false;
eof = true;
return false;
}
return true;
}
