From 8685eea9a7dd7684594470bc15eefab35262012a Mon Sep 17 00:00:00 2001
From: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Date: Sat, 1 Jun 2019 15:13:38 -0700
Subject: [PATCH] Preserve texture name from .mtl as is

For use-cases that require parsing the .obj file and outputting another
file, resolving texture paths is inconvenient since the result depends
on the path that's passed to obj_fast_read. While this can be resolved
by recomputing the relative path in user code, it seems cleaner to keep
the map names as is when parsing .mtl.

Of course, if .obj file is required for rendering, the path
concatenation is still convenient. This change makes
fastObjTexture::name contain the original data, and fastObjTexture::path
contains the resolved path that can be used to actually load the texture
if necessary.
---
 fast_obj.h | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/fast_obj.h b/fast_obj.h
index 264d033..471c075 100644
--- a/fast_obj.h
+++ b/fast_obj.h
@@ -30,9 +30,12 @@
 
 typedef struct
 {
-    /* Path to texture */
+    /* Texture name from .mtl file */
     char*                       name;
 
+    /* Resolved path to texture */
+    char*                       path;
+
 } fastObjTexture;
 
 
@@ -725,6 +728,7 @@ fastObjTexture map_default(void)
     fastObjTexture map;
 
     map.name = 0;
+    map.path = 0;
 
     return map;
 }
@@ -822,6 +826,7 @@ static
 void map_clean(fastObjTexture* map)
 {
     memory_dealloc(map->name);
+    memory_dealloc(map->path);
 }
 
 
@@ -873,6 +878,7 @@ const char* read_map(fastObjData* data, const char* ptr, fastObjTexture* map)
     const char* s;
     const char* e;
     char*       name;
+    char*       path;
 
     ptr = skip_whitespace(ptr);
 
@@ -888,10 +894,13 @@ const char* read_map(fastObjData* data, const char* ptr, fastObjTexture* map)
 
     e = ptr;
 
-    name = string_concat(data->base, s, e);
-    string_fix_separators(name);
+    name = string_copy(s, e);
+
+    path = string_concat(data->base, s, e);
+    string_fix_separators(path);
 
     map->name = name;
+    map->path = path;
 
     return e;
 }