void BlockList::Add(const vec2_t &vertex)
{
if( _blocks.empty() )
NewBlock();
Block* h = _blocks.front();
if( h->isFull() ) {
NewBlock();
h = _blocks.front();
}
h->Add( vertex );
Block* last = _blocks.back();
//see if we can disgard the last block
if(last != h && last->XRange().Disjoint(_xrange) ) {
PopBack();
}
// check if _yrange is valid, if not,
// initialize with the help of this first y value
if(isnan(_yrange.Length())) {
_yrange = Interval(vertex.y, vertex.y);
}
else {
_yrange.Extend( vertex.y );
}
}
/*
* stmt := '{' (stmt)* '}'
* | command-def
* | const-def
* | variable-def
* | expr
*/
Statement* Parser::statement() {
// Always check for block statements first! Block statements
// have a weird property: they can be interpreted as expressions
// in the expression() production rule.
if(accept(leftbrace)) {
Block* b = new Block(last.line, error);
while(sym != rightbrace && sym != finished) {
b->Add(statement());
}
expect(rightbrace);
return b;
}
else if(accept(commandsym)) {
return commanddef();
}
else if(accept(constsym)) {
return constdef();
}
// ROM writing statements
else if(accept(romsym)) {
RomWrite* stmt = new RomWrite(last.line, error);
expect(leftbracket);
stmt->SetBase(expression());
expect(rightbracket);
expect(equals);
stmt->SetValue(expression());
return stmt;
}
else if(accept(romtblsym)) {
RomWrite* stmt = new RomWrite(last.line, error);
expect(leftbracket);
stmt->SetBase(expression());
expect(comma);
stmt->SetSize(expression());
expect(comma);
stmt->SetIndex(expression());
expect(rightbracket);
expect(equals);
stmt->SetValue(expression());
return stmt;
}
// Identifiers can also begin expressions, so we have to
// peek ahead to decide which production rule to apply
/*else if(sym == identifier) {
symbol peeked = lexer->Peek();
if(peeked == colon) {
accept(identifier);
int line = last.line;
string name = last.sval;
accept(colon);
return new Label(line, name, error);
}
else {
return new ExprStmt(last.line, expression(), error);
}
}*/
// If all else fails, try it as an expression statement
return new ExprStmt(last.line, expression(), error);
}
void BlockList::NewBlock( const bool copy_last )
{
Block* b = new DataBlock();
if( !_blocks.empty() && copy_last ) {
Block* l = _blocks.front();
b->Add( l->LastValue() );
}
_blocks.push_front(b);
}
