set default color attachment format (#20073)

Mee-gu · minggo · commit 5ab04a700152 · 2019-09-04T10:07:31.000+08:00
diff --git a/cocos/renderer/backend/metal/RenderPipelineMTL.mm b/cocos/renderer/backend/metal/RenderPipelineMTL.mm
@@ -302,6 +302,8 @@ MTLBlendOperation toMTLBlendOperation(BlendOperation operation)
         // FIXME: now just handle color attachment 0.
         if (descriptor.colorAttachmentsTexture[0])
             colorFormat = descriptor.colorAttachmentsTexture[0]->getTextureFormat();
+        else
+            colorFormat = PixelFormat::DEFAULT;
     }
     else
     {

Original file line number	Diff line number	Diff line change
`@@ -302,6 +302,8 @@ MTLBlendOperation toMTLBlendOperation(BlendOperation operation)`
`302`	`302`	`// FIXME: now just handle color attachment 0.`
`303`	`303`	`if (descriptor.colorAttachmentsTexture[0])`
`304`	`304`	`colorFormat = descriptor.colorAttachmentsTexture[0]->getTextureFormat();`
	`305`	`+ else`
	`306`	`+ colorFormat = PixelFormat::DEFAULT;`
`305`	`307`	`}`
`306`	`308`	`else`
`307`	`309`	`{`