extract shader types to module

Sources/Voxelotl/shadertypes.h

@@ -0,0 +1,22 @@
+#ifndef SHADERTYPES_H
+#define SHADERTYPES_H
+
+#ifdef __METAL_VERSION__
+# define NS_ENUM(TYPE, NAME) enum NAME : TYPE NAME; enum NAME : TYPE
+# define NSInteger metal::int32_t
+#else
+# import <Foundation/Foundation.h>
+#endif
+
+#include <simd/simd.h>
+
+typedef NS_ENUM(NSInteger, ShaderInputIdx) {
+  ShaderInputIdxVertices = 0
+};
+
+typedef struct {
+  vector_float4 position;
+  vector_float4 color;
+} ShaderVertex;
+
+#endif//SHADERTYPES_H