FAQ

Compiler error: “Too many template arguments for class template ‘document_traversal’”

Increase BOOST_PARAMETER_MAX_ARITY value from default 8 value. Place define like this before any Boost or SVG++ include:

#define BOOST_PARAMETER_MAX_ARITY 15

SVG++ stops parsing on incorrect attribute value and throws exception

SVG Specification says “The document shall be rendered up to, but not including, the first element which has an error”. Therefore such behavior is correct, it will be better to fix SVG document.

But if you want to continue rendering document ignoring error in an attribute, you should inherit your class from policy::error::raise_exception, override its parse_failed method to not throw exception, but return true instead:

struct custom_error_policy: svgpp::policy::error::raise_exception<BaseContext>
{
    template<class AttributeTag, class AttributeValue>
    static bool parse_failed(BaseContext const &, AttributeTag,
                             AttributeValue const & value)
    {
        return true;
    }
};

where BaseContext is common base class for all contexts. Then pass this new class as template parameter error_policy to document_traversal class:

document_traversal<
  error_policy<custom_error_policy>
  /* ... */
>::/* ... */

Compiler is out of memory or compilation takes too long

Some compilers (e.g. Visual C++, especially 2015) may have difficulties building advanced applications that uses SVG++ library. Heavy usage of templates in SVG++ itself and also in its dependencies Boost.Spirit and Boost.MPL results in large number of templates instantiated during compilation.

SVG++ 1.1 introduces some workaround about this problem - some Boost.Spirit parsers now can be moved to another translation unit at the cost of additional call to the virtual function on each value that the parser produces.

Before first SVG++ header is included some macro should be defined for each parser to be moved:

#define SVGPP_USE_EXTERNAL_PATH_DATA_PARSER
#define SVGPP_USE_EXTERNAL_TRANSFORM_PARSER
#define SVGPP_USE_EXTERNAL_PRESERVE_ASPECT_RATIO_PARSER
#define SVGPP_USE_EXTERNAL_PAINT_PARSER
#define SVGPP_USE_EXTERNAL_MISC_PARSER
#define SVGPP_USE_EXTERNAL_COLOR_PARSER
#define SVGPP_USE_EXTERNAL_LENGTH_PARSER

And new source file should be added to the project that contains instantiations for some templates with parameters used in the application:

#include <svgpp/parser/external_function/parse_all_impl.hpp>

SVGPP_PARSE_PATH_DATA_IMPL(const char *, double)
SVGPP_PARSE_TRANSFORM_IMPL(const char *, double)
SVGPP_PARSE_PAINT_IMPL    (const char *, color_factory_t, svgpp::factory::icc_color::default_factory)
SVGPP_PARSE_COLOR_IMPL    (const char *, color_factory_t, svgpp::factory::icc_color::default_factory)
SVGPP_PARSE_PRESERVE_ASPECT_RATIO_IMPL(const char *)
SVGPP_PARSE_MISC_IMPL     (const char *, double)
SVGPP_PARSE_CLIP_IMPL     (const char *, length_factory_t)
SVGPP_PARSE_LENGTH_IMPL   (const char *, length_factory_t)

First parameters to SVGPP_PARSE_..._IMPL() macros are type of iterators that are provided by used XML parser policy. And the other parameters are coordinate type or different factories types used.