+ // save the image resolution if we have it
+ int resX, resY;
+ switch ( GetResolutionFromOptions(*image, &resX, &resY) )
+ {
+ case wxIMAGE_RESOLUTION_INCHES:
+ {
+ const double INCHES_IN_METER = 10000.0 / 254;
+ resX = int(resX * INCHES_IN_METER);
+ resY = int(resY * INCHES_IN_METER);
+ }
+ break;
+
+ case wxIMAGE_RESOLUTION_CM:
+ resX *= 100;
+ resY *= 100;
+ break;
+
+ case wxIMAGE_RESOLUTION_NONE:
+ break;
+
+ default:
+ wxFAIL_MSG( _T("unsupported image resolution units") );
+ }
+
+ if ( resX && resY )
+ png_set_pHYs( png_ptr, info_ptr, resX, resY, PNG_RESOLUTION_METER );
+