Add slang shaders for additional samples

shaders/slang/indirectdraw/ground.slang

@@ -0,0 +1,44 @@
+/* Copyright (c) 2025, Sascha Willems
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ */
+
+struct VSInput
+{
+   float4 Pos;
+   float3 Normal;
+   float2 UV;
+   float3 Color;
+};
+
+struct VSOutput
+{
+    float4 Pos : SV_POSITION;
+    float2 UV;
+};
+
+struct UBO
+{
+    float4x4 projection;
+    float4x4 modelview;
+};
+ConstantBuffer<UBO> ubo;
+
+[[vk::binding(2,0)]] Sampler2D samplerColor;
+
+[shader("vertex")]
+VSOutput vertexMain(VSInput input)
+{
+    VSOutput output;
+    output.UV = input.UV * 32.0;
+    output.Pos = mul(ubo.projection, mul(ubo.modelview, float4(input.Pos.xyz, 1.0)));
+    return output;
+}
+
+[shader("fragment")]
+float4 fragmentMain(VSOutput input)
+{
+    float4 color = samplerColor.Sample(input.UV);
+	return float4(color.rgb, 1.0);
+}