From 1328a4b96fe9a672b403f958b0861b9ad020a440 Mon Sep 17 00:00:00 2001
From: Par Winzell <par.winzell@alyx.com>
Date: Fri, 11 Jan 2019 20:47:08 -0800
Subject: [PATCH] Another, better argument parsing fix.

---
 src/FBX2glTF.cpp | 44 ++++++++++++++++----------------------------
 1 file changed, 16 insertions(+), 28 deletions(-)

diff --git a/src/FBX2glTF.cpp b/src/FBX2glTF.cpp
index c54aa02..7d44777 100644
--- a/src/FBX2glTF.cpp
+++ b/src/FBX2glTF.cpp
@@ -103,29 +103,10 @@ int main(int argc, char* argv[]) {
          "When to compute vertex normals from mesh geometry.")
       ->type_name("(never|broken|missing|always)");
 
-  bool flip_u = false;
-  bool flip_v = true;
-  app.add_flag_function(
-      "--flip-u",
-      [&](const size_t count) { flip_u = flip_u || (count > 0); },
-      "Flip all V texture coordinates.");
-
-  app.add_flag_function(
-         "--no-flip-u",
-         [&](const size_t count) { flip_u = flip_u && (count == 0); },
-         "Don't flip U texture coordinates.")
-      ->excludes("--flip-u");
-
-  app.add_flag_function(
-      "--flip-v",
-      [&](const size_t count) { flip_v = flip_v || (count > 0); },
-      "Flip all V texture coordinates.");
-
-  app.add_flag_function(
-         "--no-flip-v",
-         [&](const size_t count) { flip_v = flip_v && (count == 0); },
-         "Don't flip V texture coordinates.")
-      ->excludes("--flip-v");
+  const auto opt_flip_u = app.add_flag("--flip-u", "Flip all U texture coordinates.");
+  const auto opt_no_flip_u = app.add_flag("--no-flip-u", "Don't flip U texture coordinates.");
+  const auto opt_flip_v = app.add_flag("--flip-v", "Flip all V texture coordinates.");
+  const auto opt_no_flip_v = app.add_flag("--no-flip-v", "Don't flip V texture coordinates.");
 
   app.add_flag(
          "--pbr-metallic-rougnness",
@@ -246,21 +227,28 @@ int main(int argc, char* argv[]) {
 
   CLI11_PARSE(app, argc, argv);
 
+  bool do_flip_u = false;
+  bool do_flip_v = true;
+  // somewhat tedious way to resolve --flag vs --no-flag in order provided
+  for (const auto opt : app.parse_order()) {
+    do_flip_u = (do_flip_u || (opt == opt_flip_u)) && (opt != opt_no_flip_u);
+    do_flip_v = (do_flip_v || (opt == opt_flip_v)) && (opt != opt_no_flip_v);
+  }
   std::vector<std::function<Vec2f(Vec2f)>> texturesTransforms;
-  if (flip_u || flip_v) {
-    if (flip_u && flip_v) {
+  if (do_flip_u || do_flip_v) {
+    if (do_flip_u && do_flip_v) {
       texturesTransforms.emplace_back([](Vec2f uv) { return Vec2f(1.0 - uv[0], 1.0 - uv[1]); });
-    } else if (flip_u) {
+    } else if (do_flip_u) {
       texturesTransforms.emplace_back([](Vec2f uv) { return Vec2f(1.0 - uv[0], uv[1]); });
     } else {
       texturesTransforms.emplace_back([](Vec2f uv) { return Vec2f(uv[0], 1.0 - uv[1]); });
     }
   }
   if (verboseOutput) {
-    if (flip_u) {
+    if (do_flip_u) {
       fmt::printf("Flipping texture coordinates in the 'U' dimension.\n");
     }
-    if (!flip_v) {
+    if (!do_flip_v) {
       fmt::printf("NOT flipping texture coordinates in the 'V' dimension.\n");
     }
   }