From 03cff2150aa4ca3b0b51c63016f0dfe915e6fc07 Mon Sep 17 00:00:00 2001
From: rdi <raphael.dinge@ohmforce.com>
Date: Sun, 24 Nov 2024 15:57:54 +0100
Subject: [PATCH] Add 180 degree rotate for context output to display

---
 include/erb/DisplayContext.h   |  1 +
 include/erb/DisplayContext.hpp | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/include/erb/DisplayContext.h b/include/erb/DisplayContext.h
index 77795a8f..996ceff9 100755
--- a/include/erb/DisplayContext.h
+++ b/include/erb/DisplayContext.h
@@ -42,6 +42,7 @@ class DisplayContext
 
                   operator Storage () const;
    Storage        rotate_ccw (std::size_t width, std::size_t height) const;
+   Storage        rotate_180 (std::size_t width, std::size_t height) const;
 
    void           set (Color color);
 
diff --git a/include/erb/DisplayContext.hpp b/include/erb/DisplayContext.hpp
index e9633a01..fc1abc8a 100755
--- a/include/erb/DisplayContext.hpp
+++ b/include/erb/DisplayContext.hpp
@@ -82,6 +82,38 @@ typename DisplayContext <Format>::Storage DisplayContext <Format>::rotate_ccw (s
 
 
 
+/*
+==============================================================================
+Name : rotate_180
+==============================================================================
+*/
+
+template <typename Format>
+typename DisplayContext <Format>::Storage DisplayContext <Format>::rotate_180 (std::size_t width, std::size_t height) const
+{
+   Storage ret;
+
+   for (std::size_t x = 0 ; x < width ; ++x)
+   for (std::size_t y = 0 ; y < height ; ++y)
+   {
+      auto & d = ret [x + (y / 8) * width];
+      const auto s = _data [(width - 1 - x) + ((height - 1 - y) / 8) * width];
+      const auto b = (s & (1 << (height - 1 - y) % 8)) != 0;
+      if (b)
+      {
+         d |= 1 << y % 8;
+      }
+      else
+      {
+         d &= ~(1 << y % 8);
+      }
+   }
+
+   return ret;
+}
+
+
+
 /*
 ==============================================================================
 Name : set