From 515ff9ee637481d0e31e19830073aea9a35fdbce Mon Sep 17 00:00:00 2001 From: Dane Springmeyer Date: Mon, 28 Jan 2013 15:09:24 -0500 Subject: [PATCH] clip before transformations to avoid nan and determine max latitude at compile time rather than hardcoding 85.0511 --- include/mapnik/well_known_srs.hpp | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/include/mapnik/well_known_srs.hpp b/include/mapnik/well_known_srs.hpp index 30372439e..ac95e88df 100644 --- a/include/mapnik/well_known_srs.hpp +++ b/include/mapnik/well_known_srs.hpp @@ -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 is_known_geographic(std::string const& srs); static inline bool lonlat2merc(double * x, double * y , int point_count) { - int i; - for(i=0; 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 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; }