From ae48cb072ded868ea5fd3d9225dd2e4931542eb9 Mon Sep 17 00:00:00 2001
From: itsmattkc <itsmattkc@gmail.com>
Date: Sat, 31 Aug 2019 17:25:42 +1000
Subject: [PATCH] clear backbuffer when attaching

---
 app/render/renderframebuffer.cpp | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/app/render/renderframebuffer.cpp b/app/render/renderframebuffer.cpp
index 1149355d5..5fc21178c 100644
--- a/app/render/renderframebuffer.cpp
+++ b/app/render/renderframebuffer.cpp
@@ -86,18 +86,33 @@ void RenderFramebuffer::Release()
 
 void RenderFramebuffer::Attach(RenderTexturePtr texture)
 {
+  if (context_ == nullptr) {
+    return;
+  }
+
   texture_ = texture;
   AttachInternal(texture_->texture());
 }
 
 void RenderFramebuffer::AttachBackBuffer(RenderTexturePtr texture)
 {
+  if (context_ == nullptr) {
+    return;
+  }
+
   texture_ = texture;
   AttachInternal(texture_->back_texture());
+
+  context_->functions()->glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+  context_->functions()->glClear(GL_COLOR_BUFFER_BIT);
 }
 
 void RenderFramebuffer::Detach()
 {
+  if (context_ == nullptr) {
+    return;
+  }
+
   QOpenGLFunctions* f = context_->functions();
 
   // bind framebuffer for attaching