From da3ae06cd17494ec2d78b9c3aee6296d4108d829 Mon Sep 17 00:00:00 2001
From: Nicolas Dufresne <nicolas.dufresne@collabora.co.uk>
Date: Sat, 22 Nov 2014 11:25:23 -0500
Subject: [PATCH] glmemory: Handle upload/download flags from map

Problem was that if buffer was mapped READWRITE (state of buffers from
libav right now), mapping it READ/GL will not upload. This is because the
flag is only set when the buffer is unmapped. We can fix this by setting
the flags in map. This result in already mapped buffer that get mapped
to be read in GL will be uploaded. The problem is that if the write
mapper makes modification afterward, the modification will never get
uploaded.

https://bugzilla.gnome.org/show_bug.cgi?id=740900
---
 gst-libs/gst/gl/gstglmemory.c | 26 +++++++++++---------------
 gst-libs/gst/gl/gstglmemory.h |  1 -
 2 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/gst-libs/gst/gl/gstglmemory.c b/gst-libs/gst/gl/gstglmemory.c
index 600f78c6aa..84bb292499 100644
--- a/gst-libs/gst/gl/gstglmemory.c
+++ b/gst-libs/gst/gl/gstglmemory.c
@@ -653,9 +653,13 @@ _gl_mem_map (GstGLMemory * gl_mem, gsize maxsize, GstMapFlags flags)
             (GstGLContextThreadFunc) _upload_memory, gl_mem);
         GST_GL_MEMORY_FLAG_UNSET (gl_mem, GST_GL_MEMORY_FLAG_NEED_UPLOAD);
       }
-    } else {
+    }
+
+    if ((flags & GST_MAP_WRITE) == GST_MAP_WRITE) {
       GST_CAT_TRACE (GST_CAT_GL_MEMORY, "mapping GL texture:%u for writing",
           gl_mem->tex_id);
+      GST_GL_MEMORY_FLAG_SET (gl_mem, GST_GL_MEMORY_FLAG_NEED_DOWNLOAD);
+      GST_GL_MEMORY_FLAG_UNSET (gl_mem, GST_GL_MEMORY_FLAG_NEED_UPLOAD);
     }
 
     data = &gl_mem->tex_id;
@@ -669,33 +673,25 @@ _gl_mem_map (GstGLMemory * gl_mem, gsize maxsize, GstMapFlags flags)
             (GstGLContextThreadFunc) _download_memory, gl_mem);
         GST_GL_MEMORY_FLAG_UNSET (gl_mem, GST_GL_MEMORY_FLAG_NEED_DOWNLOAD);
       }
-    } else {
+    }
+
+    if ((flags & GST_MAP_WRITE) == GST_MAP_WRITE) {
       GST_CAT_TRACE (GST_CAT_GL_MEMORY,
           "mapping GL texture:%u for writing to system memory", gl_mem->tex_id);
+      GST_GL_MEMORY_FLAG_SET (gl_mem, GST_GL_MEMORY_FLAG_NEED_UPLOAD);
+      GST_GL_MEMORY_FLAG_UNSET (gl_mem, GST_GL_MEMORY_FLAG_NEED_DOWNLOAD);
     }
 
     data = gl_mem->data;
   }
 
-  gl_mem->map_flags = flags;
-
   return data;
 }
 
 static void
 _gl_mem_unmap (GstGLMemory * gl_mem)
 {
-  if ((gl_mem->map_flags & GST_MAP_WRITE) == GST_MAP_WRITE) {
-    if ((gl_mem->map_flags & GST_MAP_GL) == GST_MAP_GL) {
-      GST_GL_MEMORY_FLAG_SET (gl_mem, GST_GL_MEMORY_FLAG_NEED_DOWNLOAD);
-      GST_GL_MEMORY_FLAG_UNSET (gl_mem, GST_GL_MEMORY_FLAG_NEED_UPLOAD);
-    } else {
-      GST_GL_MEMORY_FLAG_SET (gl_mem, GST_GL_MEMORY_FLAG_NEED_UPLOAD);
-      GST_GL_MEMORY_FLAG_UNSET (gl_mem, GST_GL_MEMORY_FLAG_NEED_DOWNLOAD);
-    }
-  }
-
-  gl_mem->map_flags = 0;
+  /* nothing to do here */
 }
 
 static void
diff --git a/gst-libs/gst/gl/gstglmemory.h b/gst-libs/gst/gl/gstglmemory.h
index be3bed5b26..3e2e3c51d2 100644
--- a/gst-libs/gst/gl/gstglmemory.h
+++ b/gst-libs/gst/gl/gstglmemory.h
@@ -90,7 +90,6 @@ struct _GstGLMemory
   gfloat                tex_scaling[2];
 
   /* <private> */
-  GstMapFlags           map_flags;
   gpointer              data;
 
   gboolean              data_wrapped;