void Polar::RemoveDegreeStep(int index)
{
degree_steps.erase(degree_steps.begin()+index);
for(unsigned int VWi = 0; VWi<wind_speeds.size(); VWi++)
wind_speeds[VWi].speeds.erase(wind_speeds[VWi].speeds.begin()+index);
UpdateDegreeStepLookup();
}
void Polar::AddDegreeStep(double twa)
{
unsigned int Wi;
for(Wi = 0; Wi < degree_steps.size(); Wi++)
if(twa < degree_steps[Wi])
break;
degree_steps.insert(degree_steps.begin()+Wi, twa);
for(unsigned int VWi = 0; VWi<wind_speeds.size(); VWi++)
wind_speeds[VWi].speeds.insert(wind_speeds[VWi].speeds.begin()+Wi, 0);
UpdateDegreeStepLookup();
}
/* eta is a measure of efficiency of the boat, from .01 for racing boats to .5 for
heavy cruisers */
void BoatPlan::ComputeBoatSpeeds(Boat &boat, PolarMethod method, int speed)
{
// fileFileName = _T("");
if(/*polarmethod == FROM_FILE ||*/
wind_speeds.size() != num_computed_wind_speeds ||
degree_steps.size() != computed_degree_count) {
wind_speeds.clear();
degree_steps.clear();
for(unsigned int Wi = 0; Wi < computed_degree_count; Wi++)
degree_steps.push_back(computed_degree_step*Wi);
UpdateDegreeStepLookup();
for(unsigned int VWi = 0; VWi < num_computed_wind_speeds; VWi++) {
wind_speeds.push_back(SailingWindSpeed(computed_wind_speeds[VWi]));
wind_speeds[VWi].speeds.clear();
for(unsigned int Wi = 0; Wi < computed_degree_count; Wi++)
wind_speeds[VWi].speeds.push_back(SailingWindSpeed::SailingSpeed(0, degree_steps[Wi]));
}
}
// for IMF computation
double SADR = boat.SailAreaDisplacementRatio();
double lwl_ft = boat.lwl_ft;
double hull_speed = boat.HullSpeed();
int VW1i, VW2i;
if(speed == -1) // all speeds
VW1i = 0, VW2i = wind_speeds.size() - 1;
else
ClosestVWi(speed, VW1i, VW2i);
for(int VWi = VW1i; VWi <= VW2i; VWi++) {
for(unsigned int Wi = 0; Wi <= computed_degree_count/2; Wi++) {
double VW = wind_speeds[VWi].VW;
double W = Wi * computed_degree_step;
double B, VB, A, VA;
switch(method) {
case TRANSFORM:
BoatSteadyState(deg2rad(W), VW, B, VB, A, VA, boat);
break;
case IMF:
{
if(fabsf(W) < 30)
VB = 0;
else {
double base_speed = 2.62 + .066*SADR + .051*lwl_ft;
double b = 1 / sqrt(VW + 3);
VB = base_speed*(sin(deg2rad(W)/2) + b*cos(deg2rad(W))) * sqrt(20*VW) / 8;
if(VB > hull_speed)
VB = hull_speed;
}
}
default:
printf("BoatPlan::ComputeBoatSpeeds called with invalid method: %d\n", method);
return;
}
Set(Wi, VWi, VB, W);
if(W != 0) // assume symmetric performance
Set(computed_degree_count-Wi, VWi, VB, DEGREES-W);
}
CalculateVMG(VWi);
}
polarmethod = method;
}
bool BoatPlan::Open(const char *filename, wxString &message)
{
wind_speeds.clear();
degree_steps.clear();
if(filename[0] == 0)
return false;
int linenum = 0;
ZUFILE *f = zu_open(filename, "r");
char line[1024];
double lastentryW = -1;
char *token, *saveptr;
const char delim[] = ";, \t\r\n";
if(!f)
PARSE_ERROR(_("Failed to open."));
// polar file has optional first line which is description
for(;;) {
if(!zu_gets(f, line, sizeof line))
PARSE_ERROR(_("Failed to read."));
token = strtok_r(line, delim, &saveptr);
linenum++;
/* chomp invisible bytes */
while(*token < 0) token++;
if(!strcasecmp(token, "twa/tws") ||
!strcasecmp(token, "twa\\tws") ||
!strcasecmp(token, "twa"))
break;
if(linenum == 2)
PARSE_ERROR(_("Unrecognized format."));
}
while((token = strtok_r(NULL, delim, &saveptr))) {
wind_speeds.push_back(SailingWindSpeed(strtod(token, 0)));
if(wind_speeds.size() > MAX_WINDSPEEDS_IN_TABLE)
PARSE_ERROR(_("Too many wind speeds."));
}
wind_speed_step = (int)round(wind_speeds.back().VW / wind_speeds.size());
while(zu_gets(f, line, sizeof line)) {
linenum++;
#if 0
/* strip newline/linefeed */
for(unsigned int i=0; i<strlen(line); i++)
if(line[i] == '\r' || line[i] == '\n')
line[i] = '\0';
#endif
if(!(token = strtok_r(line, delim, &saveptr)))
break;
double W = strtod(token, 0);
if(W < 0 || W > 180) {
PARSE_WARNING(_("Wind direction out of range."));
continue;
}
if(W <= lastentryW) {
PARSE_WARNING(_("Wind direction out of order."));
continue;
}
// add zero speed for all wind speeds going against wind if not specified
if(degree_steps.empty() && W > 0)
{
degree_steps.push_back(0);
for(int VWi = 0; VWi < (int)wind_speeds.size(); VWi++)
wind_speeds[VWi].speeds.push_back(SailingWindSpeed::SailingSpeed(0, 0));
}
degree_steps.push_back(W);
lastentryW = W;
{
for(int VWi = 0; VWi < (int)wind_speeds.size(); VWi++) {
double s = 0;
if((token = strtok_r(NULL, delim, &saveptr)))
s = strtod(token, 0);
else
PARSE_WARNING(_("Too few tokens."));
wind_speeds[VWi].speeds.push_back
(SailingWindSpeed::SailingSpeed(s, W));
}
if(strtok_r(NULL, delim, &saveptr))
PARSE_WARNING(_("Too many tokens."));
}
}
zu_close(f);
/* fill in port tack assuming symmetric */
{
int Win = degree_steps.size()-1;
if(degree_steps[Win] == 180) Win--;
for(; Win >= 0; Win--) {
if(degree_steps[Win] == 0)
break;
degree_steps.push_back(DEGREES - degree_steps[Win]);
for(unsigned int VWi = 0; VWi < wind_speeds.size(); VWi++)
wind_speeds[VWi].speeds.push_back(wind_speeds[VWi].speeds[Win]);
}
}
UpdateDegreeStepLookup();
wind_degree_step = degree_steps.size() ? 360 / degree_steps.size() : 0;
for(unsigned int VWi = 0; VWi < wind_speeds.size(); VWi++)
CalculateVMG(VWi);
fileFileName = wxString::FromUTF8(filename);
polarmethod = FROM_FILE;
return true;
failed:
wind_speeds.clear();
degree_steps.clear();
zu_close(f);
return false;
}
