demotool/c-shaders.cc

172 lines
3.7 KiB
C++

#include "externals.hh"
#include "c-shaders.hh"
namespace {
const std::map< std::string , E_ShaderInput > InputTypes_( ([] {
std::map< std::string , E_ShaderInput > t;
t.emplace( "chunk" , E_ShaderInput::CHUNK );
t.emplace( "library" , E_ShaderInput::LIBRARY );
t.emplace( "lib" , E_ShaderInput::LIBRARY );
t.emplace( "vertex" , E_ShaderInput::VERTEX );
t.emplace( "fragment" , E_ShaderInput::FRAGMENT );
t.emplace( "compute" , E_ShaderInput::COMPUTE );
t.emplace( "geo" , E_ShaderInput::GEOMETRY );
t.emplace( "geometry" , E_ShaderInput::GEOMETRY );
return t;
})());
const std::regex PreprocDirective_( "^\\s*//!\\s*([a-z]+(\\s+([^\\s]+))*)\\s*$" );
} // namespace <anon>
/*============================================================================*/
namespace {
// Input reader state and functions, used when loading a source file
struct T_InputReader_
{
using T_Tokens_ = std::vector< std::string >;
FILE* const file;
T_ShaderInput& input;
uint32_t line{ 0 };
char* buffer{ nullptr };
ssize_t readCount;
std::string accumulator{ };
uint32_t accumLines{ 0 };
T_InputReader_( FILE* const file ,
T_ShaderInput& input )
: file( file ) , input( input )
{ }
~T_InputReader_( );
void read( );
void handleDirective( T_Tokens_ const& tokens );
void error( T_String const& err );
void nl( );
void addAccumulated( );
};
/*----------------------------------------------------------------------------*/
T_InputReader_::~T_InputReader_( )
{
if ( buffer ) {
free( buffer );
}
fclose( file );
}
void T_InputReader_::read( )
{
size_t bsz( 0 );
while ( ( readCount = getline( &buffer , &bsz , file ) ) != -1 ) {
line ++;
std::cmatch match;
if ( std::regex_match( buffer , match , PreprocDirective_ ) ) {
const T_Tokens_ tokens( ([](std::string const& a) {
using stri = std::istream_iterator< std::string >;
std::istringstream iss( a );
return T_Tokens_{ stri( iss ) , stri( ) };
})( match[ 1 ].str( ) ) );
assert( tokens.size( ) >= 1 );
handleDirective( tokens );
} else {
accumulator += buffer;
accumLines ++;
}
}
addAccumulated( );
}
/*----------------------------------------------------------------------------*/
void T_InputReader_::handleDirective(
T_Tokens_ const& tokens )
{
auto const& directive( tokens[ 0 ] );
if ( directive == "include" ) {
if ( tokens.size( ) != 2 ) {
nl( );
error( "invalid arguments" );
return;
}
addAccumulated( );
auto& ck( input.chunks );
ck.addNew( E_ShaderInputChunk::INCLUDE , tokens[ 1 ].c_str( ) , 1 );
} else if ( directive == "type" ) {
nl( );
if ( tokens.size( ) != 2 ) {
error( "invalid arguments" );
return;
}
auto pos( InputTypes_.find( tokens[ 1 ] ) );
if ( pos == InputTypes_.end( ) ) {
error( "unknown type" );
} else {
input.type = pos->second;
}
} else {
nl( );
error( "unknown directive" );
}
}
/*----------------------------------------------------------------------------*/
void T_InputReader_::error(
T_String const& err )
{
input.errors.addNew( line , err );
}
void T_InputReader_::nl( )
{
accumLines ++;
accumulator += '\n';
}
void T_InputReader_::addAccumulated( )
{
if ( accumLines ) {
auto& ck( input.chunks );
ck.addNew( E_ShaderInputChunk::CODE ,
accumulator.c_str( ) , accumLines );
accumulator = {};
accumLines = 0;
}
}
} // namespace <anon>
/*= T_ShaderInput ============================================================*/
bool T_ShaderInput::load(
T_String const& path )
{
type = E_ShaderInput::CHUNK;
chunks.clear( );
errors.clear( );
FILE* const file{ fopen( (char const*) path.toOSString( ).data( ) , "r" ) };
if ( !file ) {
return false;
}
T_InputReader_ reader( file , *this );
reader.read( );
return true;
}