From 3fe3b45dd22b97525caa22678f8927d0ddf352ca Mon Sep 17 00:00:00 2001
From: Elliott Sales de Andrade <quantum.analyst@gmail.com>
Date: Tue, 4 Aug 2020 05:54:38 -0400
Subject: [PATCH 1/2] Byte swap `agg_capture` output on big-endian systems.

R expects colours to be integers of ABGR, which on little-endian
machines maps to singular bytes in RGBA order, but maps to ABGR order on
bit-endian machines.

Signed-off-by: Elliott Sales de Andrade <quantum.analyst@gmail.com>
---
 src/AggDeviceCapture.h | 4 +++-
 src/ragg.h             | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/AggDeviceCapture.h b/src/AggDeviceCapture.h
index 02f76a4..86f7cc4 100644
--- a/src/AggDeviceCapture.h
+++ b/src/AggDeviceCapture.h
@@ -21,7 +21,9 @@ public:
   }
   SEXP capture() {
     SEXP raster = PROTECT(Rf_allocVector(INTSXP, this->width * this->height));
-    memcpy(INTEGER(raster), this->buffer, this->width * this->height * 4);
+    agg::rendering_buffer caprbuf(reinterpret_cast<agg::int8u*>(INTEGER(raster)),
+                                  this->width, this->height, this->width * 4);
+    agg::convert<pixfmt_r_capture, pixfmt_type_32>(&caprbuf, &this->rbuf);
     SEXP dims = PROTECT(Rf_allocVector(INTSXP, 2));
     INTEGER(dims)[0] = this->height;
     INTEGER(dims)[1] = this->width;
diff --git a/src/ragg.h b/src/ragg.h
index 7a66d8b..0fca0a5 100644
--- a/src/ragg.h
+++ b/src/ragg.h
@@ -36,8 +36,10 @@ typedef agg::pixfmt_rgba64_pre                  pixfmt_type_64;
 
 #ifdef __BIG_ENDIAN__ 
 typedef agg::pixfmt_abgr32_plain                pixfmt_r_raster;
+typedef agg::pixfmt_abgr32_pre                  pixfmt_r_capture;
 #else
 typedef agg::pixfmt_rgba32_plain                pixfmt_r_raster;
+typedef agg::pixfmt_rgba32_pre                  pixfmt_r_capture;
 #endif
 
 // pixfmt agnosting demultiplying
-- 
2.25.4