From e212a338d752cfc2b84a6a0582a5dceb777374e1 Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Thu, 11 Oct 2018 16:40:29 -0700
Subject: [PATCH] Load contents of previous pass before rendering geometry

---
 MetaballsKit/Renderer.swift | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/MetaballsKit/Renderer.swift b/MetaballsKit/Renderer.swift
index b39692a..56dc429 100644
--- a/MetaballsKit/Renderer.swift
+++ b/MetaballsKit/Renderer.swift
@@ -181,8 +181,10 @@ public class Renderer: NSObject, MTKViewDelegate {
                 didEncode = true
             }
 
+            let pass = renderPass.copy() as! MTLRenderPassDescriptor
+            pass.colorAttachments[0].loadAction = .load
             if let pipeline = marchingSquaresPipeline,
-               let encoder = buffer.makeRenderCommandEncoder(descriptor: renderPass) {
+               let encoder = buffer.makeRenderCommandEncoder(descriptor: pass) {
                 encoder.label = "Marching Squares Render"
                 encoder.setRenderPipelineState(pipeline)
                 encoder.setVertexBytes(points, length: points.count * MemoryLayout<Vertex>.stride, index: 0)