From 261a768ae5ba2338c6c44b4eac4574b69355cf67 Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Wed, 21 Nov 2018 08:57:59 -0700
Subject: [PATCH] Remove RandomGenerator

---
 Terrain2/Algorithms.swift                | 36 ------------------------
 Terrain2/ShaderTypes.h                   |  9 ++++--
 Terrain2/Shaders/TerrainAlgorithms.metal | 11 --------
 3 files changed, 7 insertions(+), 49 deletions(-)

diff --git a/Terrain2/Algorithms.swift b/Terrain2/Algorithms.swift
index 1e0b64f..98dce16 100644
--- a/Terrain2/Algorithms.swift
+++ b/Terrain2/Algorithms.swift
@@ -104,42 +104,6 @@ class ZeroAlgorithm: Kernel, TerrainGenerator {
     }
 }
 
-/// Randomly generate heights that are independent of all others.
-class RandomAlgorithm: Kernel, TerrainGenerator {
-    let name = "Random"
-
-    let needsGPU: Bool = true
-
-    private var uniforms: UnsafeMutablePointer<RandomAlgorithmUniforms>
-
-    init?(device: MTLDevice, library: MTLLibrary) {
-        let bufferSize = (MemoryLayout<RandomAlgorithmUniforms>.stride & ~0xFF) + 0x100;
-        guard let buffer = device.makeBuffer(length: bufferSize, options: [.storageModeShared]) else {
-            print("Couldn't create uniform buffer")
-            return nil
-        }
-
-        uniforms = UnsafeMutableRawPointer(buffer.contents()).bindMemory(to: RandomAlgorithmUniforms.self, capacity:1)
-
-        do {
-            try super.init(device: device, library: library, functionName: "randomKernel", uniformBuffer: buffer)
-        } catch let e {
-            print("Couldn't create compute kernel. Error: \(e)")
-            return nil
-        }
-
-        updateUniforms()
-    }
-
-    func updateUniforms() {
-        RandomAlgorithmUniforms_refreshRandoms(uniforms)
-    }
-
-    func render(progress: Progress) -> [Float] {
-        return []
-    }
-}
-
 /// Implementation of the Diamond-Squares algorithm.
 /// - https://en.wikipedia.org/wiki/Diamond-square_algorithm
 public class DiamondSquareGenerator: TerrainGenerator {
diff --git a/Terrain2/ShaderTypes.h b/Terrain2/ShaderTypes.h
index 5e7f919..6a45da6 100644
--- a/Terrain2/ShaderTypes.h
+++ b/Terrain2/ShaderTypes.h
@@ -66,8 +66,13 @@ typedef struct {
     matrix_float4x4 projectionMatrix;
     matrix_float4x4 modelViewMatrix;
     matrix_float3x3 normalMatrix;
-    packed_float2 terrainDimensions;
-    packed_uint2 terrainSegments;
+#ifdef __METAL_VERSION__
+    simd::packed_float2 terrainDimensions;
+    simd::packed_uint2 terrainSegments;
+#else
+    simd_packed_float2 terrainDimensions;
+    simd_packed_uint2 terrainSegments;
+#endif
 } Uniforms;
 
 #endif /* ShaderTypes_h */
diff --git a/Terrain2/Shaders/TerrainAlgorithms.metal b/Terrain2/Shaders/TerrainAlgorithms.metal
index 108757b..9b83074 100644
--- a/Terrain2/Shaders/TerrainAlgorithms.metal
+++ b/Terrain2/Shaders/TerrainAlgorithms.metal
@@ -93,14 +93,3 @@ kernel void zeroKernel(texture2d<float, access::write> outTexture [[texture(Gene
     outTexture.write(0, tid);
 }
 
-#pragma mark - RandomGenerator
-
-kernel void randomKernel(texture2d<float, access::write> outTexture [[texture(GeneratorTextureIndexOut)]],
-                         constant RandomAlgorithmUniforms &uniforms [[buffer(0)]],
-                         uint2 tid [[thread_position_in_grid]])
-{
-    PRNG rng(uniforms.randoms[(tid.x * tid.y) % kRandomAlgorithmUniforms_RandomCount]);
-    uint r = rng.xorShift();
-    float x = float(r * (1.0 / float(UINT_MAX))) * 0.5f;
-    outTexture.write(x, tid);
-}