wip: shader compilation benchmark

When parsing a lexeme, we use one less byte than it's intended to be for
comparing the current string.

This results in a success in cases like:
- true and truX
- false and falsX
- null and nulX
where X means an arbitrary character.

Fix this by the full intended length.

NEW_RELEASE_NOTES.md

@@ -7,3 +7,5 @@ for next branch cut* header.
 appropriate header in [RELEASE_NOTES.md](./RELEASE_NOTES.md).
 
 ## Release notes for next branch cut
+
+- Metal: fix some shader artifacts by disabling fast math optimizations.

android/filament-android/src/main/java/com/google/android/filament/View.java

@@ -1637,6 +1637,10 @@ public class View {
          * circle of confusion scale factor (amount of blur)
          */
         public float cocScale = 1.0f;
+        /**
+         * width/height aspect ratio of the circle of confusion (simulate anamorphic lenses)
+         */
+        public float cocAspectRatio = 1.0f;
         /**
          * maximum aperture diameter in meters (zero to disable rotation)
          */
@@ -1878,7 +1882,7 @@ public class View {
      * Options for Temporal Anti-aliasing (TAA)
      * Most TAA parameters are extremely costly to change, as they will trigger the TAA post-process
      * shaders to be recompiled. These options should be changed or set during initialization.
-     * `filterWidth`, `feedback` and `jitterPattern`, however, can be changed at any time.
+     * `filterWidth`, `feedback` and `jitterPattern`, however, could be changed at any time.
      *
      * `feedback` of 0.1 effectively accumulates a maximum of 19 samples in steady state.
      * see "A Survey of Temporal Antialiasing Techniques" by Lei Yang and all for more information.

filament/backend/src/metal/MetalShaderCompiler.mm

@@ -103,10 +103,19 @@ void MetalShaderCompiler::terminate() noexcept {
         NSString* objcSource = [[NSString alloc] initWithBytes:source.data()
                                                         length:source.size() - 1
                                                       encoding:NSUTF8StringEncoding];
+
+        // By default, Metal uses the most recent language version.
+        MTLCompileOptions* options = [MTLCompileOptions new];
+
+        // Disable Fast Math optimizations.
+        // This ensures that operations adhere to IEEE standards for floating-point arithmetic,
+        // which is crucial for half precision floats in scenarios where fast math optimizations
+        // lead to inaccuracies, such as in handling special values like NaN or Infinity.
+        options.fastMathEnabled = NO;
+
         NSError* error = nil;
-        // When options is nil, Metal uses the most recent language version available.
         id<MTLLibrary> library = [device newLibraryWithSource:objcSource
-                                                      options:nil
+                                                      options:options
                                                         error:&error];
         if (library == nil) {
             if (error) {

filament/include/filament/Options.h

@@ -293,6 +293,7 @@ struct DepthOfFieldOptions {
         MEDIAN
     };
     float cocScale = 1.0f;              //!< circle of confusion scale factor (amount of blur)
+    float cocAspectRatio = 1.0f;        //!< width/height aspect ratio of the circle of confusion (simulate anamorphic lenses)
     float maxApertureDiameter = 0.01f;  //!< maximum aperture diameter in meters (zero to disable rotation)
     bool enabled = false;               //!< enable or disable depth of field effect
     Filter filter = Filter::MEDIAN;     //!< filter to use for filling gaps in the kernel

filament/src/PostProcessManager.cpp

@@ -1428,7 +1428,7 @@ FrameGraphId<FrameGraphTexture> PostProcessManager::dof(FrameGraph& fg,
         FrameGraphId<FrameGraphTexture> depth,
         const CameraInfo& cameraInfo,
         bool translucent,
-        float bokehAspectRatio,
+        float2 bokehScale,
         const DepthOfFieldOptions& dofOptions) noexcept {
 
     assert_invariant(depth);
@@ -1818,8 +1818,8 @@ FrameGraphId<FrameGraphTexture> PostProcessManager::dof(FrameGraph& fg,
                 mi->setParameter("tiles", tilesCocMinMax,
                         { .filterMin = SamplerMinFilter::NEAREST });
                 mi->setParameter("cocToTexelScale", float2{
-                        bokehAspectRatio / (inputDesc.width  * dofResolution),
-                                     1.0 / (inputDesc.height * dofResolution)
+                        bokehScale.x / (inputDesc.width * dofResolution),
+                        bokehScale.y / (inputDesc.height * dofResolution)
                 });
                 mi->setParameter("cocToPixelScale", (1.0f / float(dofResolution)));
                 mi->setParameter("ringCounts", float4{

filament/src/PostProcessManager.h

@@ -162,7 +162,7 @@ public:
             FrameGraphId<FrameGraphTexture> depth,
             const CameraInfo& cameraInfo,
             bool translucent,
-            float bokehAspectRatio,
+            math::float2 bokehScale,
             const DepthOfFieldOptions& dofOptions) noexcept;
 
     // Bloom

filament/src/details/Renderer.cpp

@@ -1043,9 +1043,13 @@ void FRenderer::renderJob(ArenaScope& arena, FView& view) {
             // The bokeh height is always correct regardless of the dynamic resolution scaling.
             // (because the CoC is calculated w.r.t. the height), so we only need to adjust
             // the width.
-            float const bokehAspectRatio = scale.x / scale.y;
+            float const aspect = (scale.x / scale.y) * dofOptions.cocAspectRatio;
+            float2 const bokehScale{
+                aspect < 1.0f ? aspect : 1.0f,
+                aspect > 1.0f ? 1.0f / aspect : 1.0f
+            };
             input = ppm.dof(fg, input, depth, cameraInfo, needsAlphaChannel,
-                    bokehAspectRatio, dofOptions);
+                    bokehScale, dofOptions);
         }
 
         FrameGraphId<FrameGraphTexture> bloom, flare;

ios/samples/gltf-viewer/gltf-viewer/FILViewController.mm

@@ -47,6 +47,9 @@ const float kToastDelayDuration = 2.0f;
 - (void)createRenderables;
 - (void)createLights;
 
+- (void)appWillResignActive:(NSNotification*)notification;
+- (void)appDidBecomeActive:(NSNotification*)notification;
+
 @end
 
 @implementation FILViewController {
@@ -73,6 +76,16 @@ const float kToastDelayDuration = 2.0f;
 
     self.title = @"https://google.github.io/filament/remote";
 
+    // Observe lifecycle notifications to prevent us from rendering in the background.
+    [NSNotificationCenter.defaultCenter addObserver:self
+                                           selector:@selector(appWillResignActive:)
+                                               name:UIApplicationWillResignActiveNotification
+                                             object:nil];
+    [NSNotificationCenter.defaultCenter addObserver:self
+                                           selector:@selector(appDidBecomeActive:)
+                                               name:UIApplicationDidBecomeActiveNotification
+                                             object:nil];
+
     // Arguments:
     // --model <path>
     //     path to glb or gltf file to load from documents directory
@@ -125,6 +138,14 @@ const float kToastDelayDuration = 2.0f;
     [self.view addSubview:_toastLabel];
 }
 
+- (void)appWillResignActive:(NSNotification*)notification {
+    [self stopDisplayLink];
+}
+
+- (void)appDidBecomeActive:(NSNotification*)notification {
+    [self startDisplayLink];
+}
+
 - (void)viewWillAppear:(BOOL)animated {
     [self startDisplayLink];
 }
@@ -330,6 +351,7 @@ const float kToastDelayDuration = 2.0f;
 }
 
 - (void)dealloc {
+    [NSNotificationCenter.defaultCenter removeObserver:self];
     delete _server;
     delete _automation;
     self.modelView.engine->destroy(_indirectLight);

libs/viewer/src/Settings_generated.cpp

@@ -391,6 +391,8 @@ int parse(jsmntok_t const* tokens, int i, const char* jsonChunk, DepthOfFieldOpt
         CHECK_KEY(tok);
         if (compare(tok, jsonChunk, "cocScale") == 0) {
             i = parse(tokens, i + 1, jsonChunk, &out->cocScale);
+        } else if (compare(tok, jsonChunk, "cocAspectRatio") == 0) {
+            i = parse(tokens, i + 1, jsonChunk, &out->cocAspectRatio);
         } else if (compare(tok, jsonChunk, "maxApertureDiameter") == 0) {
             i = parse(tokens, i + 1, jsonChunk, &out->maxApertureDiameter);
         } else if (compare(tok, jsonChunk, "enabled") == 0) {
@@ -424,6 +426,7 @@ int parse(jsmntok_t const* tokens, int i, const char* jsonChunk, DepthOfFieldOpt
 std::ostream& operator<<(std::ostream& out, const DepthOfFieldOptions& in) {
     return out << "{\n"
         << "\"cocScale\": " << (in.cocScale) << ",\n"
+        << "\"cocAspectRatio\": " << (in.cocAspectRatio) << ",\n"
         << "\"maxApertureDiameter\": " << (in.maxApertureDiameter) << ",\n"
         << "\"enabled\": " << to_string(in.enabled) << ",\n"
         << "\"filter\": " << (in.filter) << ",\n"

libs/viewer/src/ViewerGui.cpp

@@ -1036,6 +1036,7 @@ void ViewerGui::updateUserInterface() {
             ImGui::Checkbox("Enabled##dofEnabled", &mSettings.view.dof.enabled);
             ImGui::SliderFloat("Focus distance", &mSettings.viewer.cameraFocusDistance, 0.0f, 30.0f);
             ImGui::SliderFloat("Blur scale", &mSettings.view.dof.cocScale, 0.1f, 10.0f);
+            ImGui::SliderFloat("CoC aspect-ratio", &mSettings.view.dof.cocAspectRatio, 0.25f, 4.0f);
             ImGui::SliderInt("Ring count", &dofRingCount, 1, 17);
             ImGui::SliderInt("Max CoC", &dofMaxCoC, 1, 32);
             ImGui::Checkbox("Native Resolution", &mSettings.view.dof.nativeResolution);

tools/matc/src/matc/JsonishLexer.cpp

@@ -27,9 +27,7 @@ JsonType JsonishLexer::readIdentifier() noexcept {
         consume();
     }
 
-    const char* lexemeEnd = mCursor - 1;
-
-    size_t lexemeSize = lexemeEnd - lexemeStart;
+    size_t lexemeSize = mCursor - lexemeStart;
 
     // Check what kind of keyword we got here.
     if (strncmp("true", lexemeStart, lexemeSize) == 0) {

web/filament-js/extensions_generated.js

@@ -60,6 +60,7 @@ Filament.loadGeneratedExtensions = function() {
     Filament.View.prototype.setDepthOfFieldOptionsDefaults = function(overrides) {
         const options = {
             cocScale: 1.0,
+            cocAspectRatio: 1.0,
             maxApertureDiameter: 0.01,
             enabled: false,
             filter: Filament.View$DepthOfFieldOptions$Filter.MEDIAN,

web/filament-js/filament.d.ts

@@ -1409,6 +1409,10 @@ export interface View$DepthOfFieldOptions {
      * circle of confusion scale factor (amount of blur)
      */
     cocScale?: number;
+    /**
+     * width/height aspect ratio of the circle of confusion (simulate anamorphic lenses)
+     */
+    cocAspectRatio?: number;
     /**
      * maximum aperture diameter in meters (zero to disable rotation)
      */
@@ -1659,7 +1663,7 @@ export enum View$TemporalAntiAliasingOptions$JitterPattern {
  * Options for Temporal Anti-aliasing (TAA)
  * Most TAA parameters are extremely costly to change, as they will trigger the TAA post-process
  * shaders to be recompiled. These options should be changed or set during initialization.
- * `filterWidth`, `feedback` and `jitterPattern`, however, can be changed at any time.
+ * `filterWidth`, `feedback` and `jitterPattern`, however, could be changed at any time.
  *
  * `feedback` of 0.1 effectively accumulates a maximum of 19 samples in steady state.
  * see "A Survey of Temporal Antialiasing Techniques" by Lei Yang and all for more information.

web/filament-js/jsbindings_generated.cpp

@@ -58,6 +58,7 @@ value_object<View::FogOptions>("View$FogOptions")
 
 value_object<View::DepthOfFieldOptions>("View$DepthOfFieldOptions")
     .field("cocScale", &View::DepthOfFieldOptions::cocScale)
+    .field("cocAspectRatio", &View::DepthOfFieldOptions::cocAspectRatio)
     .field("maxApertureDiameter", &View::DepthOfFieldOptions::maxApertureDiameter)
     .field("enabled", &View::DepthOfFieldOptions::enabled)
     .field("filter", &View::DepthOfFieldOptions::filter)

web/samples/CMakeLists.txt

@@ -203,7 +203,9 @@ set(HTML_FILES
     skinning.html
     suzanne.html
     test-filament-viewer.html
-    triangle.html)
+    triangle.html
+    benchmark-shader-compilation.html
+    benchmark-shader-compilation.js)
 
 set(ASSET_FILES
     assets/favicon.png)

web/samples/benchmark-shader-compilation.html

@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <title>Shader Compilation Benchmark</title>
+    <meta name="viewport" content="width=device-width,user-scalable=no,initial-scale=1">
+    <style>
+      body { margin: 0; overflow: hidden; }
+      canvas { touch-action: none; width: 100%; height: 100%; }
+      .frame-time { position: absolute; color: #ffffff;  }
+    </style>
+  </head>
+  <body>
+    <div class="frame-time">
+      Average Frame Time: <span id="frame-time-counter">Calculating...</span>
+    </div>
+    <canvas></canvas>
+    <script src="filament.js"></script>
+    <script src="gl-matrix-min.js"></script>
+    <script src="benchmark-shader-compilation.js"></script>
+  </body>
+</html>

web/samples/benchmark-shader-compilation.js

@@ -0,0 +1,141 @@
+Filament.init(['nonlit.filamat'], () => {
+  window.VertexAttribute = Filament.VertexAttribute;
+  window.AttributeType = Filament.VertexBuffer$AttributeType;
+  window.Projection = Filament.Camera$Projection;
+  window.app = new App(
+      document.getElementsByTagName('canvas')[0],
+      document.getElementById('frame-time-counter'));
+});
+
+const NUMBER_OF_TRIANGLES = 100;
+// probably 60 fps; record 1 seconds ish worth of frames.
+const NUMBER_OF_FRAMES_TO_RECORD_FPS = 1 * 60;
+
+class App {
+  constructor(canvas, frameTimeCounter) {
+    this.canvas = canvas;
+    this.frameTimeCounter = frameTimeCounter;
+
+    this.lastFrameTime = null;
+    this.frameDeltas = [];
+    for (let i = 0; i < NUMBER_OF_FRAMES_TO_RECORD_FPS; ++i) {
+      this.frameDeltas.push(0);
+    }
+    this.frameDeltasIndex = 0;
+    this.frameDeltasSum = 0;
+    this.frameTimeIsValid = false;
+
+    const engine = this.engine = Filament.Engine.create(this.canvas);
+    this.scene = engine.createScene();
+    this.triangles = [];
+    for (let i = 0; i < NUMBER_OF_TRIANGLES; ++i) {
+      const entity = Filament.EntityManager.get().create();
+      this.triangles.push({entity: entity});
+      this.scene.addEntity(entity);
+    }
+
+    const TRIANGLE_POSITIONS = new Float32Array([
+      1,
+      0,
+      Math.cos(Math.PI * 2 / 3),
+      Math.sin(Math.PI * 2 / 3),
+      Math.cos(Math.PI * 4 / 3),
+      Math.sin(Math.PI * 4 / 3),
+    ]);
+
+    const TRIANGLE_COLORS =
+        new Uint32Array([0xffff0000, 0xff00ff00, 0xff0000ff]);
+
+    this.vb =
+        Filament.VertexBuffer.Builder()
+            .vertexCount(3)
+            .bufferCount(2)
+            .attribute(VertexAttribute.POSITION, 0, AttributeType.FLOAT2, 0, 8)
+            .attribute(VertexAttribute.COLOR, 1, AttributeType.UBYTE4, 0, 4)
+            .normalized(VertexAttribute.COLOR)
+            .build(engine);
+
+    this.vb.setBufferAt(engine, 0, TRIANGLE_POSITIONS);
+    this.vb.setBufferAt(engine, 1, TRIANGLE_COLORS);
+
+    this.ib = Filament.IndexBuffer.Builder()
+                  .indexCount(3)
+                  .bufferType(Filament.IndexBuffer$IndexType.USHORT)
+                  .build(engine);
+
+    this.ib.setBuffer(engine, new Uint16Array([0, 1, 2]));
+
+    this.swapChain = engine.createSwapChain();
+    this.renderer = engine.createRenderer();
+    this.camera = engine.createCamera(Filament.EntityManager.get().create());
+
+    this.view = engine.createView();
+    this.view.setSampleCount(4);
+    this.view.setCamera(this.camera);
+    this.view.setScene(this.scene);
+
+    this.renderer.setClearOptions(
+        {clearColor: [0.0, 0.1, 0.2, 1.0], clear: true});
+
+    this.resize();
+    this.render = this.render.bind(this);
+    this.resize = this.resize.bind(this);
+    window.addEventListener('resize', this.resize);
+    window.requestAnimationFrame(this.render);
+  }
+
+  render() {
+    const frameTime = Date.now();
+    if (this.lastFrameTime) {
+      const delta = frameTime - this.lastFrameTime;
+      this.frameDeltasSum =
+          this.frameDeltasSum - this.frameDeltas[this.frameDeltasIndex] + delta;
+      this.frameDeltas[this.frameDeltasIndex] = delta;
+      this.frameDeltasIndex =
+          (this.frameDeltasIndex + 1) % NUMBER_OF_FRAMES_TO_RECORD_FPS;
+      if (this.frameDeltasIndex == 0) {
+        this.frameTimeIsValid = true;
+      }
+    }
+    this.lastFrameTime = frameTime;
+
+    if (this.frameTimeIsValid) {
+      const averageFrameDelta =
+          this.frameDeltasSum * 1.0 / NUMBER_OF_FRAMES_TO_RECORD_FPS;
+      this.frameTimeCounter.innerHTML = averageFrameDelta.toFixed(2) + ' ms';
+    }
+
+    this.triangles.forEach(triangle => {
+      if (triangle.mat) {
+        this.engine.destroyMaterial(triangle.mat);
+      }
+      triangle.mat = this.engine.createMaterial('nonlit.filamat');
+      const matinst = triangle.mat.getDefaultInstance();
+      Filament.RenderableManager.Builder(1)
+          .boundingBox({center: [-1, -1, -1], halfExtent: [1, 1, 1]})
+          .material(0, matinst)
+          .geometry(
+              0, Filament.RenderableManager$PrimitiveType.TRIANGLES, this.vb,
+              this.ib)
+          .build(this.engine, triangle.entity);
+    });
+
+    const radians = Date.now() / 1000;
+    const transform = mat4.fromRotation(mat4.create(), radians, [0, 0, 1]);
+    const tcm = this.engine.getTransformManager();
+    const inst = tcm.getInstance(this.triangles[0].entity);
+    tcm.setTransform(inst, transform);
+    inst.delete();
+    this.renderer.render(this.swapChain, this.view);
+    window.requestAnimationFrame(this.render);
+  }
+
+  resize() {
+    const dpr = window.devicePixelRatio;
+    const width = this.canvas.width = window.innerWidth * dpr;
+    const height = this.canvas.height = window.innerHeight * dpr;
+    this.view.setViewport([0, 0, width, height]);
+    const aspect = width / height;
+    this.camera.setProjection(Projection.ORTHO, -aspect, aspect, -1, 1, 0, 1);
+  }
+}