Fixed rendering, moved examples/editor option under Debug. Updated spark-viewpoint.md.

docs/docs/spark-viewpoint.md

@@ -24,6 +24,7 @@ const viewpoint = spark.newViewpoint({
   depthBias?: number;
   sort360?: boolean;
   sort32?: boolean;
+  stochastic?: boolean;
 });
 ```
 
@@ -46,6 +47,7 @@ const viewpoint = spark.newViewpoint({
 | **depthBias**     | Constant added to Z-depth to bias values into the positive range for `sortRadial: false`, but also used for culling splats "well behind" the viewpoint origin (default: `1.0`)
 | **sort360**       | Set this to true if rendering a 360 to disable "behind the viewpoint" culling during sorting. This is set automatically when rendering 360 envMaps using the `SparkRenderer.renderEnvMap()` utility function. (default: `false`)
 | **sort32**        | Set this to true to sort with float32 precision with two-pass sort. (default: `false`)
+| **stochastic**    | Set this to true to enable sort-free stochastic splat rendering. (default: `false`)
 
 ## `dispose()`
 

examples/editor/index.html

@@ -498,11 +498,6 @@
     gui.addColor(guiOptions, "backgroundColor").name("Background color").onChange((value) => {
       scene.background.set(value);
     });
-    // spark.defaultView.stochastic = true;
-    gui.add(spark.defaultView, "stochastic").name("Stochastic sort-free").listen().onChange(() => {
-      // spark.prepareViewpoint();
-      touch();
-    });
 
     const debugFolder = gui.addFolder("Debug").close();
     const normalColor = dyno.dynoBool(false);
@@ -531,6 +526,8 @@
     debugFolder.add(spark, "minAlpha", 0, 1, 0.001).name("Min alpha").listen();
 
     debugFolder.add(spark, "premultipliedAlpha").name("Premultiplied alpha").listen();
+    debugFolder.add(spark.defaultView, "stochastic").name("Stochastic sort-free").listen().onChange(touch);
+
     const accumFolder = debugFolder.addFolder("Accumulator encoding").close();;
     accumFolder.add(spark.splatEncoding, "rgbMin", -1, 1, 0.1).name("RGB min").onChange(touch);
     accumFolder.add(spark.splatEncoding, "rgbMax", 0, 4, 0.1).name("RGB max").onChange(touch);
@@ -779,8 +776,6 @@
       lastTime = time;
       stats.begin();
 
-      renderer.clear(true, true, false);
-
       if (guiOptions.autoRotate) {
         frame.rotation.y += deltaTime / 5000;
       }

src/SparkRenderer.ts

@@ -535,9 +535,10 @@ export class SparkRenderer extends THREE.Mesh {
       // Alternating debug flag that can aid in visual debugging
       this.uniforms.debugFlag.value = (performance.now() / 1000.0) % 2.0 < 1.0;
 
-      // if (viewpoint.stochastic) {
-      //   (this.geometry as SplatGeometry).instanceCount = this.uniforms.numSplats.value;
-      // }
+      if (viewpoint.display && viewpoint.stochastic) {
+        (this.geometry as SplatGeometry).instanceCount =
+          this.uniforms.numSplats.value;
+      }
     }
 
     if (viewpoint.target) {

src/SparkViewpoint.ts

@@ -571,6 +571,11 @@ export class SparkViewpoint {
 
     if (this.stochastic) {
       activeSplats = numSplats;
+      // Render all splats in order since the Z-buffer
+      // will handle ordering.
+      for (let i = 0; i < numSplats; ++i) {
+        ordering[i] = i;
+      }
     } else if (numSplats > 0) {
       const {
         reader,