fart/parser/parser.yy

%{

#include <stdio.h>
#include <iostream>
#include "main/Scene.h"
#include "main/Material.h"
#include "util/Vector.h"
#include "util/refptr.h"
#include "shapes/Shape.h"           /* includes all shape types */
using namespace std;

extern "C" {
    int yylex(void);
}

extern FILE * yyin;
extern char * yytext;

void yyerror(const char * str)
{
    fprintf(stderr, "error: %s\n", str);
}

int yywrap()
{
    return 1;
}

class Node
{
    public:
        Node();
        int type;
        refptr<double> the_double;
        refptr<Material> the_Material;
        refptr<Node> the_Node;
        refptr<Node> the_tail;
        refptr<Shape> the_Shape;
        refptr<Vector> the_Vector;
};

enum Node_Type
{
    Node_Shape = 0x42001,           /* don't clash with bison token namespace */
    Node_Camera,
    Node_Options
};

static Scene * g_scene;

#define YYSTYPE refptr<Node>

%}

%token PLUS;
%token MINUS;
%token STAR;
%token DIVIDE;
%token MOD;

%token SEMICOLON;
%token COLON;
%token QUESTION;
%token DOLLAR;
%token DOT;
%token DQUOTE;
%token SQUOTE;
%token COMMA;

%token LCURLY;
%token RCURLY;
%token LBRACKET;
%token RBRACKET;
%token LPAREN;
%token RPAREN;
%token LESS;
%token GREATER;

%token DEC_NUMBER;
%token REAL_NUMBER;

%token BOX;
%token CAMERA;
%token COLOR;
%token HEIGHT;
%token INTERSECT;
%token LOOKAT;
%token MATERIAL;
%token MULTISAMPLE;
%token OPTIONS;
%token PLANE;
%token POSITION;
%token REFLECTANCE;
%token SCENE;
%token SHININESS;
%token SIZE;
%token SPHERE;
%token SUBTRACT;
%token UNION;
%token UP;
%token VFOV;
%token WIDTH;

%%

scene: SCENE LCURLY scene_items RCURLY {
        }
     ;

boolean_items: shape shape boolean_items_more
             ;

boolean_items_more: /* empty */
                  | material boolean_items_more
                  ;

box: BOX LPAREN vector RPAREN LCURLY box_items RCURLY
   ;

box_items: shape_items { $$ = $1; }
         ;

camera: CAMERA LCURLY camera_items RCURLY {
            Vector default_position(0, -1, 0);
            Vector default_look_at(0, 0, 0);
            Vector default_up(0, 0, 1);
        }
      ;

camera_items: /* empty */
            | camera_item camera_items
            ;

camera_item: POSITION vector {
                $$ = new Node();
                $$->type = POSITION;
                $$->the_Vector = $2->the_Vector;
            }
           | LOOKAT vector {
                $$ = new Node();
                $$->type = LOOKAT;
                $$->the_Vector = $2->the_Vector;
            }
           | UP vector {
                $$ = new Node();
                $$->type = UP;
                $$->the_Vector = $2->the_Vector;
            }
           | VFOV vector {
                $$ = new Node();
                $$->type = VFOV;
                $$->the_Vector = $2->the_Vector;
            }
           ;

intersect: INTERSECT LCURLY boolean_items RCURLY
         ;

material: MATERIAL LCURLY material_items RCURLY
        ;

material_items: /* empty */
              | material_item material_items
              ;

material_item: COLOR vector {
                    $$ = new Node();
                    $$->type = COLOR;
                    $$->the_Vector = $2->the_Vector;
                }
             | REFLECTANCE number {
                    $$ = new Node();
                    $$->type = REFLECTANCE;
                    $$->the_double = $2->the_double;
                }
             | SHININESS number {
                    $$ = new Node();
                    $$->type = SHININESS;
                    $$->the_double = $2->the_double;
                }
             ;

number: DEC_NUMBER  {
            double * ptr = new double;
            *ptr = atoi(yytext);
            $$ = new Node();
            $$->the_double = ptr;
        }
      | REAL_NUMBER {
            double * ptr = new double;
            *ptr = atof(yytext);
            $$ = new Node();
            $$->the_double = ptr;
        }
      ;

options: OPTIONS LCURLY options_items RCURLY { $$ = $3; }
       ;

options_items: /* empty */
             | options_item options_items {
                    $$ = new Node();
                    $$->the_Node = $1;
                    $$->the_tail = $2;
                }
             ;

options_item: WIDTH number {
                    $$ = new Node();
                    $$->type = WIDTH;
                    $$->the_double = $2->the_double;
                }
            | HEIGHT number {
                    $$ = new Node();
                    $$->type = HEIGHT;
                    $$->the_double = $2->the_double;
                }
            | MULTISAMPLE number {
                    $$ = new Node();
                    $$->type = MULTISAMPLE;
                    $$->the_double = $2->the_double;
                }
            ;

plane: PLANE LPAREN vector COMMA number RPAREN LCURLY plane_items RCURLY {
            Plane * plane = new Plane((*($3->the_Vector))[0],
                                      (*($3->the_Vector))[1],
                                      (*($3->the_Vector))[2],
                                      *($5->the_double));
            $$ = new Node();
            $$->the_Shape = plane;
        }
     ;

plane_items: shape_items { $$ = $1; }
           ;

scene_items: /* empty */
           | scene_item scene_items {
                $$ = new Node();
                $$->the_Node = $1;
                $$->the_tail = $2;
            }
           ;

scene_item: camera { $$ = $1; $$->type = Node_Camera; }
          | shape { $$ = $1; $$->type = Node_Shape; }
          | options { $$ = $1; $$->type = Node_Options; }
          ;

shape: plane { $$ = $1; }
     | sphere { $$ = $1; }
     | box { $$ = $1; }
     | union { $$ = $1; }
     | intersect { $$ = $1; }
     | subtract { $$ = $1; }
     ;

shape_items: /* empty */
           | material { $$ = $1; }
           ;

sphere: SPHERE LPAREN number RPAREN LCURLY sphere_items RCURLY {
            Sphere * sphere = new Sphere(*($3->the_double));
            $$ = new Node();
            $$->the_Shape = sphere;
        }
      ;

sphere_items: shape_items { $$ = $1; }
            ;

subtract: SUBTRACT LCURLY boolean_items RCURLY
        ;

union: UNION LCURLY boolean_items RCURLY
     ;

vector: LESS number COMMA number COMMA number GREATER {
            Vector * ptr = new Vector();
            (*ptr)[0] = * $2->the_double;
            (*ptr)[1] = * $4->the_double;
            (*ptr)[2] = * $6->the_double;
            $$ = new Node();
            $$->the_Vector = ptr;
        }
      ;

%%

int parse(Scene * scene, const char * fileName)
{
    g_scene = scene;
    yyin = fopen(fileName, "r");
    if (yyin == NULL)
    {
        cerr << "Failed to open file '" << fileName << "'" << endl;
        return -1;
    }
    yyparse();
}

Node::Node()
{
    type = -1;
}