From 3b7b77da3af4642f9162aa47e0fff0a2ebfe784e Mon Sep 17 00:00:00 2001
From: "r.kuznetsov" <r.kuznetsov@corp.mail.ru>
Date: Mon, 17 Dec 2018 10:59:49 +0300
Subject: [PATCH] [Metal] Fixed crash on entering background

---
 drape/metal/metal_base_context.mm | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drape/metal/metal_base_context.mm b/drape/metal/metal_base_context.mm
index 52f225d48b..080e1c50b7 100644
--- a/drape/metal/metal_base_context.mm
+++ b/drape/metal/metal_base_context.mm
@@ -310,7 +310,9 @@ id<MTLRenderPipelineState> MetalBaseContext::GetPipelineState(ref_ptr<GpuProgram
   CHECK(m_currentCommandEncoder != nil, ("Probably encoding commands were called before ApplyFramebuffer."));
   
   id<MTLTexture> colorTexture = m_renderPassDescriptor.colorAttachments[0].texture;
-  CHECK(colorTexture != nil, ());
+  // It can be nil in the case when Metal drawable is absent (e.g. finish rendering in background).
+  if (colorTexture == nil)
+    return nil;
   
   id<MTLTexture> depthTexture = m_renderPassDescriptor.depthAttachment.texture;
   MTLPixelFormat depthStencilFormat = (depthTexture != nil) ? depthTexture.pixelFormat : MTLPixelFormatInvalid;