Get all the pieces together

Still doesn't render though. :\

Terrain/Renderer.swift

@@ -12,10 +12,67 @@ import MetalKit
 
 class Renderer: NSObject, MTKViewDelegate {
 
-    let device: MTLDevice
+    var device: MTLDevice!
+    var library: MTLLibrary!
+    var commandQueue: MTLCommandQueue!
+    var renderPipeline: MTLRenderPipelineState!
 
-    init(device: MTLDevice) {
+    var terrainGridSize = CGSize(width: 11, height: 11)
+    var terrain = Terrain()
+
+    func setupMetal(withDevice device: MTLDevice, pixelFormat: MTLPixelFormat) {
         self.device = device
+
+        guard let queue = device.makeCommandQueue() else {
+            fatalError("Unable to create Metal command queue")
+        }
+        queue.label = "Terrain"
+        self.commandQueue = queue
+
+        let bundle = Bundle(for: type(of: self))
+        guard let library = try? device.makeDefaultLibrary(bundle: bundle) else {
+            fatalError("Unable to create default Metal library")
+        }
+        self.library = library
+
+        setupRenderPipeline(withDevice: device, library: library, pixelFormat: pixelFormat)
+    }
+
+    func setupRenderPipeline(withDevice device: MTLDevice, library: MTLLibrary, pixelFormat: MTLPixelFormat) {
+        let vertexShader = library.makeFunction(name: "passthroughVertex")
+        let fragmentShader = library.makeFunction(name: "passthroughFragment")
+
+        let desc = MTLRenderPipelineDescriptor()
+        desc.label = "Pixel Pipeline"
+        desc.vertexFunction = vertexShader
+        desc.fragmentFunction = fragmentShader
+        if let renderAttachment = desc.colorAttachments[0] {
+            renderAttachment.pixelFormat = pixelFormat
+            // Pulled all this from SO. I don't know what it means, but it makes the alpha channel work.
+            // TODO: Learn what this means???
+            // https://stackoverflow.com/q/43727335/1174185
+            renderAttachment.isBlendingEnabled = true
+            renderAttachment.alphaBlendOperation = .add
+            renderAttachment.rgbBlendOperation = .add
+            renderAttachment.sourceRGBBlendFactor = .sourceAlpha
+            renderAttachment.sourceAlphaBlendFactor = .sourceAlpha
+            renderAttachment.destinationRGBBlendFactor = .oneMinusSourceAlpha
+            renderAttachment.destinationAlphaBlendFactor = .oneMinusSourceAlpha
+        }
+
+        do {
+            renderPipeline = try device.makeRenderPipelineState(descriptor: desc)
+        } catch let e {
+            print("Couldn't set up pixel pipeline! \(e)")
+            renderPipeline = nil
+        }
+    }
+
+    func prepareToRender() {
+        guard let buffer = device.makeBuffer(length: terrain.minimumBufferSize(forGridSize: terrainGridSize), options: .storageModeShared) else {
+            fatalError("Couldn't create terrain buffer")
+        }
+        terrain.generateVertexes(intoBuffer: buffer, size: terrainGridSize)
     }
 
     func mtkView(_ view: MTKView, drawableSizeWillChange size: CGSize) {
@@ -23,7 +80,29 @@ class Renderer: NSObject, MTKViewDelegate {
     }
 
     func draw(in view: MTKView) {
-        // TODO.
+        guard let buffer = commandQueue.makeCommandBuffer() else {
+            return
+        }
+
+        var didEncode = false
+        buffer.label = "Terrain"
+
+        if let renderPass = view.currentRenderPassDescriptor {
+            if let encoder = buffer.makeRenderCommandEncoder(descriptor: renderPass) {
+                encoder.label = "Terrain"
+                encoder.setRenderPipelineState(renderPipeline)
+                encoder.setVertexBuffer(terrain.buffer, offset: 0, index: 0)
+                encoder.drawPrimitives(type: .triangle, vertexStart: 0, vertexCount: terrain.vertexCount(forGridSize: terrainGridSize))
+                encoder.setTriangleFillMode(.lines)
+                encoder.endEncoding()
+                didEncode = true
+            }
+        }
+
+        if didEncode, let drawable = view.currentDrawable {
+            buffer.present(drawable)
+        }
+        buffer.commit()
     }
 
 }