From 2b409afc2d0e2cf149d68dd60b65e73ac3427214 Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Tue, 1 Aug 2017 19:01:20 -0700
Subject: [PATCH] [MetaballsKit] Add a metal file to the framework

---
 Metaballs.xcodeproj/project.pbxproj |  4 ++++
 MetaballsKit/SamplingKernel.metal   | 24 ++++++++++++++++++++++++
 2 files changed, 28 insertions(+)
 create mode 100644 MetaballsKit/SamplingKernel.metal

diff --git a/Metaballs.xcodeproj/project.pbxproj b/Metaballs.xcodeproj/project.pbxproj
index e08f7c8..08b37fa 100644
--- a/Metaballs.xcodeproj/project.pbxproj
+++ b/Metaballs.xcodeproj/project.pbxproj
@@ -21,6 +21,7 @@
 		C0BBE3AA1F2E91D900E68524 /* Shaders.metal in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3A91F2E91D900E68524 /* Shaders.metal */; };
 		C0BBE3AC1F2E941200E68524 /* Renderer.swift in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3AB1F2E941200E68524 /* Renderer.swift */; };
 		C0BBE3AD1F30CD7E00E68524 /* MetalKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C0BBE3A71F2E893A00E68524 /* MetalKit.framework */; };
+		C0BBE3AF1F314C8200E68524 /* SamplingKernel.metal in Sources */ = {isa = PBXBuildFile; fileRef = C0BBE3AE1F314C8200E68524 /* SamplingKernel.metal */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -60,6 +61,7 @@
 		C0BBE3A71F2E893A00E68524 /* MetalKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = MetalKit.framework; path = System/Library/Frameworks/MetalKit.framework; sourceTree = SDKROOT; };
 		C0BBE3A91F2E91D900E68524 /* Shaders.metal */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.metal; path = Shaders.metal; sourceTree = "<group>"; };
 		C0BBE3AB1F2E941200E68524 /* Renderer.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Renderer.swift; sourceTree = "<group>"; };
+		C0BBE3AE1F314C8200E68524 /* SamplingKernel.metal */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.metal; path = SamplingKernel.metal; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -150,6 +152,7 @@
 				C0BBE38E1F2E81B600E68524 /* MetaballsKit.h */,
 				C0BBE38F1F2E81B600E68524 /* Info.plist */,
 				C0BBE3A31F2E81C700E68524 /* Metaballs.swift */,
+				C0BBE3AE1F314C8200E68524 /* SamplingKernel.metal */,
 			);
 			path = MetaballsKit;
 			sourceTree = "<group>";
@@ -369,6 +372,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				C0BBE3A41F2E81C700E68524 /* Metaballs.swift in Sources */,
+				C0BBE3AF1F314C8200E68524 /* SamplingKernel.metal in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
diff --git a/MetaballsKit/SamplingKernel.metal b/MetaballsKit/SamplingKernel.metal
new file mode 100644
index 0000000..90a2de8
--- /dev/null
+++ b/MetaballsKit/SamplingKernel.metal
@@ -0,0 +1,24 @@
+//
+//  SamplingKernel.metal
+//  Metaballs
+//
+//  Created by Eryn Wells on 8/1/17.
+//  Copyright © 2017 Eryn Wells. All rights reserved.
+//
+
+#include <metal_stdlib>
+using namespace metal;
+
+typedef struct {
+    float radius;
+    float2 position;
+    float2 velocity;
+} Ball;
+
+kernel void
+sampleFieldKernel(const device Ball* metaballs      [[buffer(0)]],
+                  texture2d<half, access::write>    [[texture(1)]],
+                  uint2 gid                         [[thread_position_in_grid]])
+{
+    // TODO: Compute a sample for this pixel given the field data, and write it to the out texture.
+}