Add shaders re-implemented in HLSL

These were written against the shaders at revision eddd724e7.
There have been changes made since then, which will need to be mirrored.

See `data/hlsl/README.md` for the current status of each sample.

data/hlsl/bloom/colorpass.frag

@@ -0,0 +1,15 @@
+// Copyright 2020 Google LLC
+
+Texture2D colorMapTexture : register(t1);
+SamplerState colorMapSampler : register(s1);
+
+struct VSOutput
+{
+	[[vk::location(0)]]float3 Color : COLOR0;
+	[[vk::location(1)]]float2 UV : TEXCOORD0;
+};
+
+float4 main(VSOutput input) : SV_TARGET
+{
+	return float4(input.Color, 1);
+}

data/hlsl/bloom/colorpass.vert

@@ -0,0 +1,31 @@
+// Copyright 2020 Google LLC
+
+struct VSInput
+{
+	[[vk::location(0)]]float4 Pos : POSITION0;
+	[[vk::location(1)]]float2 UV : TEXCOORD0;
+	[[vk::location(2)]]float3 Color : COLOR0;
+};
+
+struct VSOutput
+{
+	float4 Pos : SV_POSITION;
+	[[vk::location(0)]]float3 Color : COLOR0;
+	[[vk::location(1)]]float2 UV : TEXCOORD0;
+};
+
+cbuffer UBO : register(b0)
+{
+	float4x4 projection;
+	float4x4 view;
+	float4x4 model;
+};
+
+VSOutput main(VSInput input)
+{
+	VSOutput output = (VSOutput)0;
+	output.UV = input.UV;
+	output.Color = input.Color;
+	output.Pos = mul(projection, mul(view, mul(model, input.Pos)));
+	return output;
+}

data/hlsl/bloom/gaussblur.frag

@@ -0,0 +1,43 @@
+// Copyright 2020 Google LLC
+
+Texture2D textureColor : register(t1);
+SamplerState samplerColor : register(s1);
+
+cbuffer UBO : register(b0)
+{
+	float blurScale;
+	float blurStrength;
+};
+
+[[vk::constant_id(0)]] const int blurdirection = 0;
+
+float4 main([[vk::location(0)]] float2 inUV : TEXCOORD0) : SV_TARGET
+{
+	float weight[5];
+	weight[0] = 0.227027;
+	weight[1] = 0.1945946;
+	weight[2] = 0.1216216;
+	weight[3] = 0.054054;
+	weight[4] = 0.016216;
+
+	float2 textureSize;
+	textureColor.GetDimensions(textureSize.x, textureSize.y);
+	float2 tex_offset = 1.0 / textureSize * blurScale; // gets size of single texel
+	float3 result = textureColor.Sample(samplerColor, inUV).rgb * weight[0]; // current fragment's contribution
+	for(int i = 1; i < 5; ++i)
+	{
+		if (blurdirection == 1)
+		{
+			// H
+			result += textureColor.Sample(samplerColor, inUV + float2(tex_offset.x * i, 0.0)).rgb * weight[i] * blurStrength;
+			result += textureColor.Sample(samplerColor, inUV - float2(tex_offset.x * i, 0.0)).rgb * weight[i] * blurStrength;
+		}
+		else
+		{
+			// V
+			result += textureColor.Sample(samplerColor, inUV + float2(0.0, tex_offset.y * i)).rgb * weight[i] * blurStrength;
+			result += textureColor.Sample(samplerColor, inUV - float2(0.0, tex_offset.y * i)).rgb * weight[i] * blurStrength;
+		}
+	}
+	return float4(result, 1.0);
+}

data/hlsl/bloom/gaussblur.vert

@@ -0,0 +1,15 @@
+// Copyright 2020 Google LLC
+
+struct VSOutput
+{
+	float4 Pos : SV_POSITION;
+	[[vk::location(0)]] float2 UV : TEXCOORD0;
+};
+
+VSOutput main(uint VertexIndex : SV_VertexID)
+{
+	VSOutput output = (VSOutput)0;
+	output.UV = float2((VertexIndex << 1) & 2, VertexIndex & 2);
+	output.Pos = float4(output.UV * 2.0f - 1.0f, 0.0f, 1.0f);
+	return output;
+}

data/hlsl/bloom/phongpass.frag

@@ -0,0 +1,32 @@
+// Copyright 2020 Google LLC
+
+Texture2D colorMapTexture : register(t1);
+SamplerState colorMapSampler : register(s1);
+
+struct VSOutput
+{
+[[vk::location(0)]] float3 Normal : NORMAL0;
+[[vk::location(1)]] float2 UV : TEXCOORD0;
+[[vk::location(2)]] float3 Color : COLOR0;
+[[vk::location(3)]] float3 ViewVec : TEXCOORD1;
+[[vk::location(4)]] float3 LightVec : TEXCOORD2;
+};
+
+float4 main(VSOutput input) : SV_TARGET
+{
+	float3 ambient = float3(0.0f, 0.0f, 0.0f);
+
+	// Adjust light calculations for glow color
+	if ((input.Color.r >= 0.9) || (input.Color.g >= 0.9) || (input.Color.b >= 0.9))
+	{
+		ambient = input.Color * 0.25;
+	}
+
+	float3 N = normalize(input.Normal);
+	float3 L = normalize(input.LightVec);
+	float3 V = normalize(input.ViewVec);
+	float3 R = reflect(-L, N);
+	float3 diffuse = max(dot(N, L), 0.0) * input.Color;
+	float3 specular = pow(max(dot(R, V), 0.0), 8.0) * float3(0.75f, 0.75f, 0.75f);
+	return float4(ambient + diffuse + specular, 1.0);
+}

data/hlsl/bloom/phongpass.vert

@@ -0,0 +1,42 @@
+// Copyright 2020 Google LLC
+
+struct VSInput
+{
+[[vk::location(0)]] float4 Pos : POSITION0;
+[[vk::location(1)]] float2 UV : TEXCOORD0;
+[[vk::location(2)]] float3 Color : COLOR0;
+[[vk::location(3)]] float3 Normal : NORMAL0;
+};
+
+struct VSOutput
+{
+	float4 Pos : SV_POSITION;
+[[vk::location(0)]] float3 Normal : NORMAL0;
+[[vk::location(1)]] float2 UV : TEXCOORD0;
+[[vk::location(2)]] float3 Color : COLOR0;
+[[vk::location(3)]] float3 ViewVec : TEXCOORD1;
+[[vk::location(4)]] float3 LightVec : TEXCOORD2;
+};
+
+cbuffer UBO : register(b0)
+{
+	float4x4 projection;
+	float4x4 view;
+	float4x4 model;
+};
+
+VSOutput main(VSInput input)
+{
+	VSOutput output = (VSOutput)0;
+	output.Normal = input.Normal;
+	output.Color = input.Color;
+	output.UV = input.UV;
+	output.Pos = mul(projection, mul(view, mul(model, input.Pos)));
+
+	float3 lightPos = float3(-5.0, -5.0, 0.0);
+	float4 pos = mul(view, mul(model, input.Pos));
+	output.Normal = mul((float4x3)mul(view, model), input.Normal).xyz;
+	output.LightVec = lightPos - pos.xyz;
+	output.ViewVec = -pos.xyz;
+	return output;
+}

data/hlsl/bloom/skybox.frag

@@ -0,0 +1,9 @@
+// Copyright 2020 Google LLC
+
+TextureCube textureCubeMap : register(t1);
+SamplerState samplerCubeMap : register(s1);
+
+float4 main([[vk::location(0)]] float3 inUVW : NORMAL0) : SV_TARGET
+{
+	return textureCubeMap.Sample(samplerCubeMap, inUVW);
+}

data/hlsl/bloom/skybox.vert

@@ -0,0 +1,22 @@
+// Copyright 2020 Google LLC
+
+cbuffer UBO : register(b0)
+{
+	float4x4 projection;
+	float4x4 view;
+	float4x4 model;
+};
+
+struct VSOutput
+{
+	float4 Pos : SV_POSITION;
+	[[vk::location(0)]] float3 UVW : NORMAL0;
+};
+
+VSOutput main([[vk::location(0)]] float3 inPos : POSITION0)
+{
+	VSOutput output = (VSOutput)0;
+	output.UVW = inPos;
+	output.Pos = mul(projection, mul(view, mul(model, float4(inPos.xyz, 1.0))));
+	return output;
+}