Add shaders for marching squares

MetaballsKit/Shaders.metal

@@ -7,13 +7,9 @@
 //
 
 #include <metal_stdlib>
+#include "ShaderTypes.hh"
 using namespace metal;
 
-struct Vertex {
-    float2 position;
-    float2 textureCoordinate;
-};
-
 // From HelloCompute sample code project.
 // Vertex shader outputs and per-fragmeht inputs. Includes clip-space position and vertex outputs interpolated by rasterizer and fed to each fragment genterated by clip-space primitives.
 struct RasterizerData {
@@ -43,10 +39,6 @@ struct Parameters {
     float3x3 colorTransform;
 };
 
-struct RenderParameters {
-    float4x4 projection;
-};
-
 typedef float3 Ball;
 
 #pragma mark - Vertex