UE4在VR模式下去掉两侧黑边

正常用VR模式打开以后，就会成这样：

红框部分就是我所说的黑边

通过改变代码，可以实现如下效果：

我们同样要在编译版的UE4下操作，这样才能重新编译到源文件（UE4源文件下载和编译请参见我上一篇文章）

在SteamVRRender.cpp里的RenderTexture_RenderThread函数修改：

修改为：

void FSteamVRHMD::RenderTexture_RenderThread(FRHICommandListImmediate& RHICmdList, FTexture2DRHIParamRef BackBuffer, FTexture2DRHIParamRef SrcTexture) const
{
	check(IsInRenderingThread());

	if (WindowMirrorMode == 0)
	{
		return;
	}

	const uint32 ViewportWidth = BackBuffer->GetSizeX();
	const uint32 ViewportHeight = BackBuffer->GetSizeY();

	SetRenderTarget(RHICmdList, BackBuffer, FTextureRHIRef());
	RHICmdList.SetViewport(0, 0, 0, ViewportWidth, ViewportHeight, 1.0f);

	RHICmdList.SetBlendState(TStaticBlendState<>::GetRHI());
	RHICmdList.SetRasterizerState(TStaticRasterizerState<>::GetRHI());
	RHICmdList.SetDepthStencilState(TStaticDepthStencilState<false, CF_Always>::GetRHI());

	const auto FeatureLevel = GMaxRHIFeatureLevel;
	auto ShaderMap = GetGlobalShaderMap(FeatureLevel);

	TShaderMapRef<FScreenVS> VertexShader(ShaderMap);
	TShaderMapRef<FScreenPS> PixelShader(ShaderMap);

	static FGlobalBoundShaderState BoundShaderState;
	SetGlobalBoundShaderState(RHICmdList, FeatureLevel, BoundShaderState, RendererModule->GetFilterVertexDeclaration().VertexDeclarationRHI, *VertexShader, *PixelShader);

	PixelShader->SetParameters(RHICmdList, TStaticSamplerState<SF_Bilinear>::GetRHI(), SrcTexture);

	if (WindowMirrorMode == 1)
	{
		// need to clear when rendering only one eye since the borders won't be touched by the DrawRect below
		RHICmdList.Clear(true, FLinearColor::Black, false, 0, false, 0, FIntRect());

		RendererModule->DrawRectangle(
			RHICmdList,
			0, 0,
			ViewportWidth, ViewportHeight,
			0.0f, 0.3f,
			0.4f, 0.4f,
			FIntPoint(ViewportWidth, ViewportHeight),
			FIntPoint(1, 1),
			*VertexShader,
			EDRF_Default);
	}
	else if (WindowMirrorMode == 2)
	{
		RendererModule->DrawRectangle(
			RHICmdList,
			0, 0,
			ViewportWidth, ViewportHeight,
			0.0f, 0.0f,
			1.0f, 1.0f,
			FIntPoint(ViewportWidth, ViewportHeight),
			FIntPoint(1, 1),
			*VertexShader,
			EDRF_Default);
	}
}

原理：https://forums.unrealengine.com/showthread.php?117032-Problem-about-monitor-resolution-display-in-vive-vr-mode

此链接里写得很清楚，就不复述了=.=

So easy 吧~^^