+
+ // perform material edits
+ struct ts_node *child = node->child_list;
+ while(child) {
+ proc_mtledit(newscn, child); // ignores any non-mtledit nodes, no need to check
+ child = child->next;
+ }
+
+ scn->merge(newscn);
+ delete newscn;
+ }
+ //datamap_reset(); // TODO this should be push/pop instead of hard reset
+
+ return true;
+}
+
+static void mtledit(Material *mtl, TextureSet *texset, struct ts_node *node)
+{
+ node = node->child_list;
+ while(node) {
+ struct ts_node *cn = node;
+ node = node->next;
+
+ if(strcmp(cn->name, "texture") == 0) {
+ // add/change/remove a texture
+ struct ts_attr *atype = ts_get_attr(cn, "type");
+ struct ts_attr *afile = ts_get_attr(cn, "file");
+
+ int textype = MTL_TEX_DIFFUSE;
+ if(atype) {
+ if(atype->val.type == TS_STRING) {
+ textype = mtl_parse_type(atype->val.str);
+ } else if(atype->val.type == TS_NUMBER) {
+ textype = atype->val.inum;
+ if(textype < 0 || textype >= NUM_MTL_TEXTURES) {
+ error_log("invalid texture in mtledit: %d\n", textype);
+ continue;
+ }
+ } else {
+ error_log("unexpected texture type in mtledit: %s\n", atype->val.str);
+ continue;
+ }
+ }
+
+ if(!afile || !afile->val.str || !*afile->val.str) {
+ // remove
+ mtl->textures[textype] = 0;
+ } else {
+ Texture *tex = texset->get_texture(afile->val.str, TEX_2D);
+ mtl->add_texture(tex, textype);
+ }
+ }
+ // TODO add more edit modes
+ }
+}
+
+static bool proc_mtledit(Scene *scn, struct ts_node *node)
+{
+ if(strcmp(node->name, "mtledit") != 0) {
+ return false;
+ }
+
+ const char *mtl_regexp = ".*";
+ struct ts_attr *amtl = ts_get_attr(node, "material");
+ if(amtl && amtl->val.type == TS_STRING) {
+ mtl_regexp = amtl->val.str;
+ }
+
+ // search all the objects to find matching material names
+ std::regex re{mtl_regexp};
+
+ int nobj = scn->objects.size();
+ for(int i=0; i<nobj; i++) {
+ Object *obj = scn->objects[i];
+ if(std::regex_match(obj->get_name(), re)) {
+ mtledit(&obj->mtl, scn->texset, node);
+ }