From 14072ce0261aa68ef1a37fe45ac143f94dae8de3 Mon Sep 17 00:00:00 2001
From: themancalledjakob <jakob@jrkb.land>
Date: Fri, 7 Apr 2023 09:47:45 +0200
Subject: [PATCH] add vFlip detection algorithm

---
 src/Utils.cpp | 45 +++++++++++++++++++++++++++++++++++++++++++++
 src/Utils.h   | 19 +++++++++++++++++++
 2 files changed, 64 insertions(+)
 create mode 100644 src/Utils.cpp

diff --git a/src/Utils.cpp b/src/Utils.cpp
new file mode 100644
index 0000000..37fc210
--- /dev/null
+++ b/src/Utils.cpp
@@ -0,0 +1,45 @@
+#include "Utils.h"
+
+namespace ofxVariableLab {
+
+void getVFlip(const VFlipBehaviour & vFlipBehaviour,
+              const glm::mat4 & orientationMatrix,
+              VFlipState & vFlip){
+    switch(vFlipBehaviour){
+
+     case V_FLIP_ONCE_AUTO: {
+         if(vFlip != V_FLIP_UNKNOWN){
+             break;
+         }
+     }
+
+     case V_FLIP_ALWAYS_AUTO: {
+         if(orientationMatrix == glm::mat4(1)){
+             vFlip = V_FLIP_OFF;
+         }else{
+             vFlip = V_FLIP_ON;
+         }
+         break;
+     }
+
+     case V_FLIP_ALWAYS_ON: {
+         vFlip = V_FLIP_ON;
+         break;
+     }
+
+     case V_FLIP_ALWAYS_OFF: {
+         vFlip = V_FLIP_OFF;
+         break;
+     }
+    }
+}
+//getVFlip(settings.vFlipBehaviour,
+//ofGetCurrentOrientationMatrix(),
+//vFlip);
+//if(vFlip == V_FLIP_OFF){
+//ofTranslate(pl * magic, (pt * magic) + (-1 * h), 0);
+////ofTranslate(pl * magic, -1 * pt * magic, 0);
+//}else{
+//ofTranslate(pl * magic, -1 * pt * magic, 0);
+//}
+}
diff --git a/src/Utils.h b/src/Utils.h
index 017fe3b..fbaff93 100644
--- a/src/Utils.h
+++ b/src/Utils.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <string>
+#include <glm/glm.hpp>
 
 namespace ofxVariableLab {
 
@@ -21,5 +22,23 @@ inline void hash_combine(std::size_t & seed, const T & v){
     std::hash <T> hasher;
     seed ^= hasher(v) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
 }
+enum VFlipState {
+    V_FLIP_UNKNOWN = 0,
+    V_FLIP_ON,
+    V_FLIP_OFF
+};
+enum VFlipBehaviour {
+    /// probe view matrix every frame
+    V_FLIP_ALWAYS_AUTO = 0,
+    /// probe view matrix once and remember
+    V_FLIP_ONCE_AUTO,
+    /// never probe and force off
+    V_FLIP_ALWAYS_OFF,
+    /// never probe and force on
+    V_FLIP_ALWAYS_ON
+};
+void getVFlip(const VFlipBehaviour & vFlipBehaviour,
+              const glm::mat4 & orientationMatrix,
+              VFlipState & vFlip);
 
 }