Clean up vertex inputs

Fixes #766

data/shaders/hlsl/offscreen/mirror.frag

@@ -5,8 +5,7 @@ SamplerState samplerColor : register(s1);
 
 struct VSOutput
 {
-[[vk::location(0)]] float2 UV : TEXCOORD0;
-[[vk::location(1)]] float4 ProjCoord : POSITION0;
+[[vk::location(0)]] float4 ProjCoord : POSITION0;
 };
 
 float4 main(VSOutput input, bool FrontFacing : SV_IsFrontFace) : SV_TARGET

data/shaders/hlsl/offscreen/mirror.vert

@@ -3,7 +3,6 @@
 struct VSInput
 {
 [[vk::location(0)]] float3 Pos : POSITION0;
-[[vk::location(1)]] float2 UV : TEXCOORD0;
 };
 
 struct UBO
@@ -18,14 +17,12 @@ cbuffer ubo : register(b0) { UBO ubo; }
 struct VSOutput
 {
 	float4 Pos : SV_POSITION;
-[[vk::location(0)]] float2 UV : TEXCOORD0;
-[[vk::location(1)]] float4 ProjCoord : POSITION0;
+[[vk::location(0)]] float4 ProjCoord : POSITION0;
 };
 
 VSOutput main(VSInput input)
 {
 	VSOutput output = (VSOutput)0;
-	output.UV = input.UV;
 	output.ProjCoord = mul(ubo.projection, mul(ubo.view, mul(ubo.model, float4(input.Pos.xyz, 1.0))));
 	output.Pos = output.ProjCoord;
 	return output;