qbsp: add -objexport flag to export to obj

qbsp/CMakeLists.txt

@@ -32,6 +32,7 @@ set(QBSP_SOURCES
 	wad.c
 	winding.c
 	writebsp.c
+	exportobj.c
 	${QBSP_INCLUDES})
 
 add_definitions(-DDOUBLEVEC_T)

qbsp/exportobj.c

@@ -0,0 +1,97 @@
+/*
+    Copyright (C) 2016       Eric Wasylishen
+
+    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.
+
+    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
+
+    See file, 'COPYING', for details.
+*/
+
+#include "qbsp.h"
+#include "wad.h"
+
+static FILE *
+InitObjFile(void)
+{
+    FILE *objfile;
+    
+    StripExtension(options.szBSPName);
+    strcat(options.szBSPName, ".obj");
+    objfile = fopen(options.szBSPName, "wt");
+    if (!objfile)
+        Error("Failed to open %s: %s", options.szBSPName, strerror(errno));
+    
+    return objfile;
+}
+
+static void
+GetUV(const texinfo_t *texinfo, const vec_t *pos, const int width, const int height, vec_t *u, vec_t *v)
+{
+    *u = (pos[0]*texinfo->vecs[0][0] + pos[1]*texinfo->vecs[0][1] + pos[2]*texinfo->vecs[0][2] + texinfo->vecs[0][3]) / width;
+    *v = (pos[0]*texinfo->vecs[1][0] + pos[1]*texinfo->vecs[1][1] + pos[2]*texinfo->vecs[1][2] + texinfo->vecs[1][3]) / height;
+}
+
+static void
+ExportObjFace(FILE *f, const face_t *face, int *vertcount)
+{
+    const texinfo_t *texinfos = pWorldEnt->lumps[LUMP_TEXINFO].data;
+    const texinfo_t *texinfo = &texinfos[face->texinfo];
+    const char *texname = map.miptex[texinfo->miptex];
+    
+    const texture_t *texture = WADList_GetTexture(texname);
+    const int width = texture ? texture->width : 64;
+    const int height = texture ? texture->height : 64;
+    
+    // export the vertices and uvs
+    for (int i=0; i<face->w.numpoints; i++)
+    {
+        const vec_t *pos = face->w.points[i];
+        fprintf(f, "v %.9g %.9g %.9g\n", pos[0], pos[1], pos[2]);
+        
+        vec_t u, v;
+        GetUV(texinfo, pos, width, height, &u, &v);
+        
+        // not sure why -v is needed, .obj uses (0, 0) in the top left apparently?
+        fprintf(f, "vt %.9g %.9g\n", u, -v);
+    }
+    
+    fprintf(f, "usemtl %s\n", texname);
+    fprintf(f, "f");
+    for (int i=0; i<face->w.numpoints; i++) {
+        // .obj vertexes start from 1
+        // .obj faces are CCW, quake is CW, so reverse the order
+        const int vertindex = *vertcount + (face->w.numpoints - 1 - i) + 1;
+        fprintf(f, " %d/%d", vertindex, vertindex);
+    }
+    fprintf(f, "\n");
+    
+    *vertcount += face->w.numpoints;
+}
+
+void
+ExportObj(const surface_t *surfaces)
+{
+    FILE *objfile = InitObjFile();
+    int vertcount = 0;
+    
+    const surface_t *surf;
+    for (surf = surfaces; surf; surf = surf->next) {
+        const face_t *face;
+        for (face = surf->faces; face; face = face->next) {
+            ExportObjFace(objfile, face, &vertcount);
+        }
+    }
+    
+    fclose(objfile);
+}

qbsp/qbsp.c

@@ -133,6 +133,10 @@ ProcessEntity(mapentity_t *entity, const int hullnum)
     surfs = CSGFaces(entity);
     FreeBrushes(entity->brushes);
 
+    if (options.fObjExport && entity == pWorldEnt && hullnum == 0) {
+        ExportObj(surfs);
+    }
+    
     if (hullnum != 0) {
         nodes = SolidBSP(entity, surfs, true);
         if (entity == pWorldEnt && !options.fNofill) {
@@ -608,6 +612,7 @@ PrintOptions(void)
            "   -oldrottex      Use old rotate_ brush texturing aligned at (0 0 0)\n"
            "   -maxnodesize [n]Triggers simpler BSP Splitting when node exceeds size (default 1024, 0 to disable)\n"
            "   -epsilon [n]    Customize ON_EPSILON (default 0.0001)\n"
+           "   -objexport      Export the map file as an .OBJ model after the CSG phase\n"
            "   sourcefile      .MAP file to process\n"
            "   destfile        .BSP file to output\n");
 
@@ -779,6 +784,8 @@ ParseOptions(char *szOptions)
                     Error("Invalid argument to option %s", szTok);
                 options.on_epsilon= atof(szTok2);
                 szTok = szTok2;
+            } else if (!Q_strcasecmp(szTok, "objexport")) {
+                options.fObjExport = true;
             } else if (!Q_strcasecmp(szTok, "?") || !Q_strcasecmp(szTok, "help"))
                 PrintOptions();
             else

qbsp/qbsp.h

@@ -485,6 +485,7 @@ typedef struct options_s {
     char szBSPName[512];
     char wadPath[512];
     vec_t on_epsilon;
+    bool fObjExport;
 } options_t;
 
 extern options_t options;
@@ -598,6 +599,8 @@ void BSPX_Brushes_Finalize(struct bspxbrushes_s *ctx);
 void BSPX_Brushes_Init(struct bspxbrushes_s *ctx);
 void BSPX_Brushes_AddModel(struct bspxbrushes_s *ctx, int modelnum, brush_t *brushes);
 
+void ExportObj(const surface_t *surfaces);
+
 // util.c
 
 #define msgWarning      1

qbsp/wad.c

@@ -28,12 +28,15 @@ static void WADList_LoadTextures(const wad_t *wadlist, dmiptexlump_t *lump);
 static int WAD_LoadLump(const wad_t *wad, const char *name, byte *dest);
 static void WADList_AddAnimationFrames(const wad_t *wadlist);
 
+static texture_t *textures;
+
 static bool
 WAD_LoadInfo(wad_t *wad)
 {
     wadinfo_t *hdr = &wad->header;
     int i, len, lumpinfosize, disksize;
     dmiptex_t miptex;
+    texture_t *tex;
 
     len = fread(hdr, 1, sizeof(wadinfo_t), wad->file);
     if (len != sizeof(wadinfo_t))
@@ -54,6 +57,24 @@ WAD_LoadInfo(wad_t *wad)
     if (len != lumpinfosize)
         return false;
 
+    /* Get the dimensions and make a texture_t */
+    for (i = 0; i < wad->header.numlumps; i++) {
+        fseek(wad->file, wad->lumps[i].filepos, SEEK_SET);
+        len = fread(&miptex, 1, sizeof(miptex), wad->file);
+        if (len == sizeof(miptex))
+        {
+            tex = AllocMem(OTHER, sizeof(texture_t), true);
+            tex->next = textures;
+            textures = tex;
+            memcpy(tex->name, miptex.name, 16);
+            tex->name[15] = '\0';
+            tex->width = miptex.width;
+            tex->height = miptex.height;
+
+            //printf("Created texture_t %s %d %d\n", tex->name, tex->width, tex->height);
+        }
+    }
+
     if (wad->version == 2)
         return true;
 
@@ -273,3 +294,14 @@ WADList_AddAnimationFrames(const wad_t *wadlist)
 
     Message(msgStat, "%8d texture frames added", map.nummiptex - oldcount);
 }
+
+const texture_t *WADList_GetTexture(const char *name)
+{
+    texture_t *tex;
+    for (tex = textures; tex; tex = tex->next)
+    {
+        if (!strcmp(name, tex->name))
+            return tex;
+    }
+    return NULL;
+}

qbsp/wad.h

@@ -40,6 +40,12 @@ typedef struct {
     char name[16];              // must be null terminated
 } lumpinfo_t;
 
+typedef struct texture_s {
+    char name[16];
+    int width, height;
+    struct texture_s *next;
+} texture_t;
+
 #define MIPLEVELS 4
 typedef struct {
     char name[16];
@@ -58,5 +64,7 @@ typedef struct wad_s {
 wad_t *WADList_Init(const char *wadstring);
 void WADList_Process(const wad_t *wadlist);
 void WADList_Free(wad_t *wadlist);
+const texture_t *WADList_GetTexture(const char *name);
+// for getting a texture width/height
 
 #endif /* WAD_H */