From cae2b2883bba3b666cfa5b8ba95eecbf0b8e2dea Mon Sep 17 00:00:00 2001
From: ManoloFLTK <41016272+ManoloFLTK@users.noreply.github.com>
Date: Sun, 9 Oct 2022 22:45:58 +0200
Subject: [PATCH] Fl_Cairo_Graphics_Driver: make image drawing correct whatever
 the host endianness.

---
 src/drivers/Cairo/Fl_Cairo_Graphics_Driver.cxx | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/src/drivers/Cairo/Fl_Cairo_Graphics_Driver.cxx b/src/drivers/Cairo/Fl_Cairo_Graphics_Driver.cxx
index 48c6120c6..4421bd610 100644
--- a/src/drivers/Cairo/Fl_Cairo_Graphics_Driver.cxx
+++ b/src/drivers/Cairo/Fl_Cairo_Graphics_Driver.cxx
@@ -831,10 +831,8 @@ void Fl_Cairo_Graphics_Driver::cache(Fl_RGB_Image *rgb) {
           A = *(r+3);
           f = float(A)/0xff;
         }
-        *q =  B * f;
-        *(q+1) =  G * f;
-        *(q+2) =  R * f;
-        *(q+3) =  A;
+        // this produces ARGB data in native endian
+        *(uint32_t *)q = A << 24 | (uchar)(R*f) << 16 | (uchar)(G*f) << 8 | (uchar)(B*f);
         r += rgb->d(); q += 4;
       }
     }
@@ -848,10 +846,9 @@ void Fl_Cairo_Graphics_Driver::cache(Fl_RGB_Image *rgb) {
           A = *(r+1);
           f = float(A)/0xff;
         }
-        *(q) =  G * f;
-        *(q+1) =  G * f;
-        *(q+2) =  G * f;
-        *(q+3) =  A;
+        G = (uchar)(G * f);
+        // this produces ARGB data in native endian
+        *(uint32_t *)q = A << 24 | G << 16 | G << 8 | G;
         r += rgb->d(); q += 4;
       }
     }