Hi, i wrote another example called dwg2dxf.c to export dxf from dwg.
Olli
/*****************************************************************************/ /* LibreDWG - free implementation of the DWG file format */ /* */ /* Copyright (C) 2009 Free Software Foundation, Inc. */ /* Copyright (C) 2010 Thien-Thi Nguyen */ /* Copyright (C) 2014 Oliver Dippel */ /* */ /* This library is free software, licensed under the terms of the GNU */ /* General Public License as published by the Free Software Foundation, */ /* either version 3 of the License, or (at your option) any later version. */ /* You should have received a copy of the GNU General Public License */ /* along with this program. If not, see <http://www.gnu.org/licenses/>. */ /*****************************************************************************/ /* * testDXF.c: convert a DWG to DXF * written by Oliver Dippel <[email protected]> */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <math.h> #include <dwg.h> #include "../src/bits.h" #include "suffix.c" #define PI 3.14159265 #define toDeg(x) (x*180.0)/PI int export_DXF(char *filename); void output_DXF(Dwg_Data* dwg); double model_xmin, model_ymin; double page_width, page_height, scale; int main (int argc, char *argv[]) { REQUIRE_INPUT_FILE_ARG (argc); return export_DXF(argv[1]); } int export_DXF (char *filename) { int error; Dwg_Data dwg; error = dwg_read_file(filename, &dwg); if (!error) { output_DXF(&dwg); } dwg_free(&dwg); return error ? 1 : 0; } void output_TEXT (Dwg_Object* obj) { Dwg_Entity_TEXT* text; text = obj->tio.entity->tio.TEXT; if (text->text_value[0] == '&') return; printf(" 0\nMTEXT\n 999\n#%d\n 10\n%f\n 20\n%f\n 40\n%f\n 1\n%s\n", obj->index, text->insertion_pt.x, text->insertion_pt.y + text->height, text->height, text->text_value); } void output_LINE (Dwg_Object* obj) { Dwg_Entity_LINE* line; line = obj->tio.entity->tio.LINE; printf(" 0\nLINE\n 999\n#%d\n 10\n%f\n 20\n%f\n 11\n%f\n 21\n%f\n", obj->index, line->start.x, line->start.y, line->end.x, line->end.y); } void output_CIRCLE (Dwg_Object* obj) { Dwg_Entity_CIRCLE* circle; circle = obj->tio.entity->tio.CIRCLE; printf(" 0\nCIRCLE\n 999\n#%d\n 10\n%f\n 20\n%f\n 40\n%f\n", obj->index, circle->center.x, circle->center.y, circle->radius); } void output_ARC (Dwg_Object* obj) { Dwg_Entity_ARC* arc; arc = obj->tio.entity->tio.ARC; printf(" 0\nARC\n 999\n#%d\n 10\n%f\n 20\n%f\n 40\n%f\n 50\n%f\n 51\n%f\n", obj->index, arc->center.x, arc->center.y, arc->radius, toDeg(arc->start_angle), toDeg(arc->end_angle)); } void output_INSERT (Dwg_Object* obj) { Dwg_Entity_INSERT* insert; insert = obj->tio.entity->tio.INSERT; } void output_object (Dwg_Object* obj) { if (!obj) { fprintf(stderr, "object is NULL\n"); return; } if (obj->type == DWG_TYPE_INSERT) { output_INSERT(obj); } if (obj->type == DWG_TYPE_LINE) { output_LINE(obj); } if (obj->type == DWG_TYPE_CIRCLE) { output_CIRCLE(obj); } if (obj->type == DWG_TYPE_TEXT) { output_TEXT(obj); } if (obj->type == DWG_TYPE_ARC) { output_ARC(obj); } } void output_BLOCK_HEADER(Dwg_Object_Ref* ref) { Dwg_Object* obj; Dwg_Object_BLOCK_HEADER* hdr; if (!ref) { fprintf(stderr, "Found null object reference. Could not output an DXF symbol for this BLOCK_HEADER\n"); return; } if (!ref->obj) { fprintf(stderr, "Found null ref->obj\n"); return; } if (!ref->obj->tio.object) { fprintf(stderr, "Found null ref->obj->tio.object\n"); return; } hdr = ref->obj->tio.object->tio.BLOCK_HEADER; obj = get_first_owned_object(ref->obj, hdr); while(obj) { output_object(obj); obj = get_next_owned_object(ref->obj, obj, hdr); } } void output_DXF(Dwg_Data* dwg) { unsigned int i; Dwg_Object *obj; model_xmin = dwg_model_x_min(dwg); model_ymin = dwg_model_y_min(dwg); double dx = (dwg_model_x_max(dwg) - dwg_model_x_min(dwg)); double dy = (dwg_model_y_max(dwg) - dwg_model_y_min(dwg)); double scale_x = dx / (dwg_page_x_max(dwg) - dwg_page_x_min(dwg)); double scale_y = dy / (dwg_page_y_max(dwg) - dwg_page_y_min(dwg)); page_width = dx; page_height = dy; printf("999\n"); printf("dxflib 2.2.0.0\n"); printf(" 0\n"); printf("SECTION\n"); printf(" 2\n"); printf("ENTITIES\n"); obj = &dwg->object[0]; if (obj->type != DWG_TYPE_BLOCK_CONTROL) { fprintf(stderr, "ERROR: First object is not a BLOCK_CONTROL\n"); return; } Dwg_Object_BLOCK_CONTROL* block_control; block_control = obj->tio.object->tio.BLOCK_CONTROL; for (i=0; i<block_control->num_entries; i++) { output_BLOCK_HEADER(block_control->block_headers[i]); } output_BLOCK_HEADER(block_control->model_space); output_BLOCK_HEADER(block_control->paper_space); printf(" 0\n"); printf("ENDSEC\n"); }
