Add slang shaders for distance field fonts sample

Author: SaschaWillems

shaders/slang/distancefieldfonts/bitmap.slang

@@ -0,0 +1,40 @@
+/* Copyright (c) 2025, Sascha Willems
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ */
+
+struct VSInput
+{
+	float3 Pos;
+	float2 UV;
+};
+
+struct VSOutput
+{
+	float4 Pos : SV_POSITION;
+	float2 UV;
+};
+
+struct UBO
+{
+    float4x4 projection;
+    float4x4 model;
+};
+ConstantBuffer<UBO> ubo;
+Sampler2D samplerColor;
+
+[shader("vertex")]
+VSOutput vertexMain(VSInput input)
+{
+    VSOutput output;
+    output.UV = input.UV;
+    output.Pos = mul(ubo.projection, mul(ubo.model, float4(input.Pos.xyz, 1.0)));
+    return output;
+}
+
+[shader("fragment")]
+float4 fragmentMain(VSOutput input)
+{
+    return samplerColor.Sample(input.UV).aaaa;
+}

shaders/slang/distancefieldfonts/sdf.slang

@@ -0,0 +1,56 @@
+/* Copyright (c) 2025, Sascha Willems
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ */
+
+struct VSInput
+{
+    float3 Pos;
+    float2 UV;
+};
+
+
+struct VSOutput
+{
+    float4 Pos : SV_POSITION;
+    float2 UV;
+};
+
+struct UBO
+{
+    float4x4 projection;
+    float4x4 model;
+    float4 outlineColor;
+    float outlineWidth;
+    float outline;
+};
+ConstantBuffer<UBO> ubo;
+Sampler2D samplerColor;
+
+[shader("vertex")]
+VSOutput vertexMain(VSInput input)
+{
+    VSOutput output;
+    output.UV = input.UV;
+    output.Pos = mul(ubo.projection, mul(ubo.model, float4(input.Pos.xyz, 1.0)));
+    return output;
+}
+
+[shader("fragment")]
+float4 fragmentMain(VSOutput input)
+{
+    float dist = samplerColor.Sample(input.UV).a;
+    float smoothWidth = fwidth(dist);
+    float alpha = smoothstep(0.5 - smoothWidth, 0.5 + smoothWidth, dist);
+	float3 rgb = alpha.xxx;
+
+	if (ubo.outline > 0.0)
+	{
+		float w = 1.0 - ubo.outlineWidth;
+		alpha = smoothstep(w - smoothWidth, w + smoothWidth, dist);
+        rgb += lerp(alpha.xxx, ubo.outlineColor.rgb, alpha);
+    }
+
+    return float4(rgb, alpha);
+}