add zip archiver library to compress cubes exporter

engine/canvas.cpp

@@ -1263,6 +1263,9 @@ void ui::Canvas::export_anim(std::string data_path)
 
 void ui::Canvas::export_cubes(std::string data_path)
 {
+#ifdef __OBJC__
+    NSMutableArray* files = [NSMutableArray array];
+#endif
 	std::array<std::string, 6> names {
 		"pz", "px", "nz", "nx",
 		"py", "ny"
@@ -1322,9 +1325,20 @@ void ui::Canvas::export_cubes(std::string data_path)
 					NSLog(@"error saving to photos : %@", error);
 				}
 			}];
+#endif
+#ifdef __OBJC__
+            [files addObject:[NSString stringWithUTF8String : name]];
 #endif
 		}
 	}
+#ifdef __OBJC__
+    static char name[128];
+    sprintf(name, "%s.zip", data_path.c_str());
+    auto zip_path = [NSString stringWithUTF8String : name];
+    [SSZipArchive createZipFileAtPath:zip_path withFilesAtPaths:files];
+    for (NSString* f : files)
+        [[NSFileManager defaultManager] removeItemAtPath:f error:nil];
+#endif
 }
 
 void ui::Canvas::project_save(std::string file_path)