openscad/src/expr.cc

244 lines
8.0 KiB
C++

/*
* OpenSCAD (www.openscad.org)
* Copyright (C) 2009-2011 Clifford Wolf <clifford@clifford.at> and
* Marius Kintel <marius@kintel.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* As a special exception, you have permission to link this program
* with the CGAL library and distribute executables, as long as you
* follow the requirements of the GNU GPL in regard to all of the
* software in the executable aside from CGAL.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "expression.h"
#include "value.h"
#include "evalcontext.h"
#include <assert.h>
#include <sstream>
#include <algorithm>
#include "stl-utils.h"
#include "printutils.h"
#include <boost/bind.hpp>
#include <boost/foreach.hpp>
Expression::Expression() : recursioncount(0)
{
}
Expression::Expression(const std::string &type,
Expression *left, Expression *right)
: type(type), recursioncount(0)
{
this->children.push_back(left);
this->children.push_back(right);
}
Expression::Expression(const std::string &type, Expression *expr)
: type(type), recursioncount(0)
{
this->children.push_back(expr);
}
Expression::Expression(const Value &val) : const_value(val), type("C"), recursioncount(0)
{
}
Expression::~Expression()
{
std::for_each(this->children.begin(), this->children.end(), del_fun<Expression>());
}
class FuncRecursionGuard
{
public:
FuncRecursionGuard(const Expression &e) : expr(e) {
expr.recursioncount++;
}
~FuncRecursionGuard() { expr.recursioncount--; }
bool recursion_detected() const { return (expr.recursioncount > 1000); }
private:
const Expression &expr;
};
Value Expression::evaluate(const Context *context) const
{
if (this->type == "!")
return ! this->children[0]->evaluate(context);
if (this->type == "&&")
return this->children[0]->evaluate(context) && this->children[1]->evaluate(context);
if (this->type == "||")
return this->children[0]->evaluate(context) || this->children[1]->evaluate(context);
if (this->type == "*")
return this->children[0]->evaluate(context) * this->children[1]->evaluate(context);
if (this->type == "/")
return this->children[0]->evaluate(context) / this->children[1]->evaluate(context);
if (this->type == "%")
return this->children[0]->evaluate(context) % this->children[1]->evaluate(context);
if (this->type == "+")
return this->children[0]->evaluate(context) + this->children[1]->evaluate(context);
if (this->type == "-")
return this->children[0]->evaluate(context) - this->children[1]->evaluate(context);
if (this->type == "<")
return this->children[0]->evaluate(context) < this->children[1]->evaluate(context);
if (this->type == "<=")
return this->children[0]->evaluate(context) <= this->children[1]->evaluate(context);
if (this->type == "==")
return this->children[0]->evaluate(context) == this->children[1]->evaluate(context);
if (this->type == "!=")
return this->children[0]->evaluate(context) != this->children[1]->evaluate(context);
if (this->type == ">=")
return this->children[0]->evaluate(context) >= this->children[1]->evaluate(context);
if (this->type == ">")
return this->children[0]->evaluate(context) > this->children[1]->evaluate(context);
if (this->type == "?:") {
return this->children[this->children[0]->evaluate(context) ? 1 : 2]->evaluate(context);
}
if (this->type == "[]") {
return this->children[0]->evaluate(context)[this->children[1]->evaluate(context)];
}
if (this->type == "I")
return -this->children[0]->evaluate(context);
if (this->type == "C")
return this->const_value;
if (this->type == "R") {
Value v1 = this->children[0]->evaluate(context);
Value v2 = this->children[1]->evaluate(context);
if (this->children.size() == 2) {
if (v1.type() == Value::NUMBER && v2.type() == Value::NUMBER) {
Value::RangeType range(v1.toDouble(), v2.toDouble());
return Value(range);
}
} else {
Value v3 = this->children[2]->evaluate(context);
if (v1.type() == Value::NUMBER && v2.type() == Value::NUMBER && v3.type() == Value::NUMBER) {
Value::RangeType range(v1.toDouble(), v2.toDouble(), v3.toDouble());
return Value(range);
}
}
return Value();
}
if (this->type == "V") {
Value::VectorType vec;
BOOST_FOREACH(const Expression *e, this->children) {
vec.push_back(e->evaluate(context));
}
return Value(vec);
}
if (this->type == "L")
return context->lookup_variable(this->var_name);
if (this->type == "N")
{
Value v = this->children[0]->evaluate(context);
if (v.type() == Value::VECTOR && this->var_name == "x")
return v[0];
if (v.type() == Value::VECTOR && this->var_name == "y")
return v[1];
if (v.type() == Value::VECTOR && this->var_name == "z")
return v[2];
if (v.type() == Value::RANGE && this->var_name == "begin")
return Value(v[0]);
if (v.type() == Value::RANGE && this->var_name == "step")
return Value(v[1]);
if (v.type() == Value::RANGE && this->var_name == "end")
return Value(v[2]);
return Value();
}
if (this->type == "F") {
FuncRecursionGuard g(*this);
if (g.recursion_detected()) {
PRINTB("ERROR: Recursion detected calling function '%s'", this->call_funcname);
return Value();
}
EvalContext c(context, this->call_arguments);
return context->evaluate_function(this->call_funcname, &c);
}
abort();
}
std::string Expression::toString() const
{
std::stringstream stream;
if (this->type == "*" || this->type == "/" || this->type == "%" || this->type == "+" ||
this->type == "-" || this->type == "<" || this->type == "<=" || this->type == "==" ||
this->type == "!=" || this->type == ">=" || this->type == ">" ||
this->type == "&&" || this->type == "||") {
stream << "(" << *this->children[0] << " " << this->type << " " << *this->children[1] << ")";
}
else if (this->type == "?:") {
stream << "(" << *this->children[0] << " ? " << *this->children[1] << " : " << *this->children[2] << ")";
}
else if (this->type == "[]") {
stream << *this->children[0] << "[" << *this->children[1] << "]";
}
else if (this->type == "I") {
stream << "-" << *this->children[0];
}
else if (this->type == "!") {
stream << "!" << *this->children[0];
}
else if (this->type == "C") {
stream << this->const_value;
}
else if (this->type == "R") {
stream << "[" << *this->children[0] << " : " << *this->children[1];
if (this->children.size() > 2) {
stream << " : " << *this->children[2];
}
stream << "]";
}
else if (this->type == "V") {
stream << "[";
for (size_t i=0; i < this->children.size(); i++) {
if (i > 0) stream << ", ";
stream << *this->children[i];
}
stream << "]";
}
else if (this->type == "L") {
stream << this->var_name;
}
else if (this->type == "N") {
stream << *this->children[0] << "." << this->var_name;
}
else if (this->type == "F") {
stream << this->call_funcname << "(";
for (size_t i=0; i < this->call_arguments.size(); i++) {
const Assignment &arg = this->call_arguments[i];
if (i > 0) stream << ", ";
if (!arg.first.empty()) stream << arg.first << " = ";
stream << *arg.second;
}
stream << ")";
}
else {
assert(false && "Illegal expression type");
}
return stream.str();
}
std::ostream &operator<<(std::ostream &stream, const Expression &expr)
{
stream << expr.toString();
return stream;
}