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/particlefire/normalmap.frag

@@ -0,0 +1,44 @@
+// Copyright 2020 Google LLC
+
+Texture2D textureColorMap : register(t1);
+SamplerState samplerColorMap : register(s1);
+Texture2D textureNormalHeightMap : register(t2);
+SamplerState samplerNormalHeightMap : register(s2);
+
+#define lightRadius 45.0
+
+struct VSOutput
+{
+[[vk::location(0)]] float2 UV : TEXCOORD0;
+[[vk::location(1)]] float3 LightVec : TEXCOORD2;
+[[vk::location(2)]] float3 LightVecB : TEXCOORD3;
+[[vk::location(3)]] float3 LightDir : TEXCOORD4;
+[[vk::location(4)]] float3 ViewVec : TEXCOORD1;
+};
+
+float4 main(VSOutput input) : SV_TARGET
+{
+	float3 specularColor = float3(0.85, 0.5, 0.0);
+
+	float invRadius = 1.0/lightRadius;
+	float ambient = 0.25;
+
+	float3 rgb, normal;
+
+	rgb = textureColorMap.Sample(samplerColorMap, input.UV).rgb;
+	normal = normalize((textureNormalHeightMap.Sample(samplerNormalHeightMap, input.UV).rgb - 0.5) * 2.0);
+
+	float distSqr = dot(input.LightVecB, input.LightVecB);
+	float3 lVec = input.LightVecB * rsqrt(distSqr);
+
+	float atten = max(clamp(1.0 - invRadius * sqrt(distSqr), 0.0, 1.0), ambient);
+	float diffuse = clamp(dot(lVec, normal), 0.0, 1.0);
+
+	float3 light = normalize(-input.LightVec);
+	float3 view = normalize(input.ViewVec);
+	float3 reflectDir = reflect(-light, normal);
+
+	float specular = pow(max(dot(view, reflectDir), 0.0), 4.0);
+
+	return float4((rgb * atten + (diffuse * rgb + 0.5 * specular * specularColor.rgb)) * atten, 1.0);
+}