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clip before transformations to avoid nan and determine max latitude at compile time rather than hardcoding 85.0511

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Dane Springmeyer 2013-01-28 15:09:24 -05:00
parent 5720c0d476
commit 515ff9ee63
1 changed files with 11 additions and 12 deletions
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23
include/mapnik/well_known_srs.hpp
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@ -51,6 +51,7 @@ static const double D2R = M_PI / 180;
static const double R2D = 180 / M_PI;
static const double M_PIby360 = M_PI / 360;
static const double MAXEXTENTby180 = MAXEXTENT / 180;
static const double MAX_LATITUDE = R2D * (2 * std::atan(std::exp(180 * D2R)) - M_PI_by2);
static const std::string MAPNIK_LONGLAT_PROJ = "+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs";
static const std::string MAPNIK_GMERC_PROJ = "+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0.0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs +over";
@ -60,31 +61,29 @@ boost::optional<bool> is_known_geographic(std::string const& srs);
static inline bool lonlat2merc(double * x, double * y , int point_count)
{
int i;
for(i=0; i<point_count; i++) {
for(int i=0; i<point_count; i++) {
if (x[i] > 180) x[i] = 180;
else if (x[i] < -180) x[i] = -180;
if (y[i] > MAX_LATITUDE) y[i] = MAX_LATITUDE;
else if (y[i] < -MAX_LATITUDE) y[i] = -MAX_LATITUDE;
x[i] = x[i] * MAXEXTENTby180;
y[i] = std::log(std::tan((90 + y[i]) * M_PIby360)) * R2D;
y[i] = y[i] * MAXEXTENTby180;
if (x[i] > MAXEXTENT) x[i] = MAXEXTENT;
if (x[i] < -MAXEXTENT) x[i] = -MAXEXTENT;
if (y[i] > MAXEXTENT) y[i] = MAXEXTENT;
if (y[i] < -MAXEXTENT) y[i] = -MAXEXTENT;
}
return true;
}
static inline bool merc2lonlat(double * x, double * y , int point_count)
{
int i;
for(i=0; i<point_count; i++)
for(int i=0; i<point_count; i++)
{
if (x[i] > MAXEXTENT) x[i] = MAXEXTENT;
else if (x[i] < -MAXEXTENT) x[i] = -MAXEXTENT;
if (y[i] > MAXEXTENT) y[i] = MAXEXTENT;
else if (y[i] < -MAXEXTENT) y[i] = -MAXEXTENT;
x[i] = (x[i] / MAXEXTENT) * 180;
y[i] = (y[i] / MAXEXTENT) * 180;
y[i] = R2D * (2 * std::atan(std::exp(y[i] * D2R)) - M_PI_by2);
if (x[i] > 180) x[i] = 180;
if (x[i] < -180) x[i] = -180;
if (y[i] > 85.0511) y[i] = 85.0511;
if (y[i] < -85.0511) y[i] = -85.0511;
}
return true;
}