Merge pull request #12933 from CesiumGS/voxel-rte

Use eye coordinates for voxel raymarching

Author: jjhembd

Apps/Sandcastle/gallery/Voxel Picking.html

@@ -80,15 +80,17 @@
           this.names = ["color"];
           this.types = [Cesium.MetadataType.VEC4];
           this.componentTypes = [Cesium.MetadataComponentType.FLOAT32];
-          this._levelCount = 3;
+          this.availableLevels = 3;
           this.globalTransform = globalTransform;
         }
 
         ProceduralMultiTileVoxelProvider.prototype.requestData = function (options) {
           const { tileLevel, tileX, tileY, tileZ } = options;
 
-          if (tileLevel >= this._levelCount) {
-            return Promise.reject(`No tiles available beyond level ${this._levelCount}`);
+          if (tileLevel >= this.availableLevels) {
+            return Promise.reject(
+              `No tiles available beyond level ${this.availableLevels - 1}`,
+            );
           }
 
           const dimensions = this.dimensions;
@@ -174,6 +176,7 @@
             customShader: customShader,
           });
           voxelPrimitive.nearestSampling = true;
+          voxelPrimitive.stepSize = 0.7;
 
           viewer.scene.primitives.add(voxelPrimitive);
           camera.flyToBoundingSphere(voxelPrimitive.boundingSphere, {

Apps/Sandcastle/gallery/Voxels.html

@@ -123,14 +123,14 @@
           this.componentTypes = [Cesium.MetadataComponentType.FLOAT32];
           this.globalTransform = globalTransform;
 
-          this._levelCount = 2;
-          this._allVoxelData = new Array(this._levelCount);
+          this.availableLevels = 2;
+          this._allVoxelData = new Array(this.availableLevels);
 
           const allVoxelData = this._allVoxelData;
           const channelCount = Cesium.MetadataType.getComponentCount(this.types[0]);
           const { dimensions } = this;
 
-          for (let level = 0; level < this._levelCount; level++) {
+          for (let level = 0; level < this.availableLevels; level++) {
             const dimAtLevel = Math.pow(2, level);
             const voxelCountX = dimensions.x * dimAtLevel;
             const voxelCountY = dimensions.y * dimAtLevel;
@@ -158,9 +158,9 @@
         ProceduralMultiTileVoxelProvider.prototype.requestData = function (options) {
           const { tileLevel, tileX, tileY, tileZ } = options;
 
-          if (tileLevel >= this._levelCount) {
+          if (tileLevel >= this.availableLevels) {
             return Promise.reject(
-              `No tiles available beyond level ${this._levelCount - 1}`,
+              `No tiles available beyond level ${this.availableLevels - 1}`,
             );
           }
 

CHANGES.md

@@ -6,6 +6,10 @@
 
 ### @cesium/engine
 
+#### Breaking Changes :mega:
+
+- Voxel rendering now requires a WebGL2 context, which is [enabled by default since 1.101](https://github.com/CesiumGS/cesium/pull/10894). For voxel rendering, make sure the `requestWebGl1` flag in `contextOptions` is NOT set to true.
+
 #### Fixes :wrench:
 
 - Materials loaded from type now respect submaterials present in the referenced material type. [#10566](https://github.com/CesiumGS/cesium/issues/10566)
@@ -17,6 +21,7 @@
 - Prevent runtime errors for certain forms of invalid PNTS files [#12872](https://github.com/CesiumGS/cesium/issues/12872)
 - Improved performance of clamped labels. [#12905](https://github.com/CesiumGS/cesium/pull/12905)
 - Fixes issue where multiple instances of a Gaussian splat tileset would transform tile positions incorrectly and render out of position. [#12795](https://github.com/CesiumGS/cesium/issues/12795)
+- Converted voxel raymarching to eye coordinates to fix precision issues in large datasets. [#12061](https://github.com/CesiumGS/cesium/issues/12061)
 
 #### Additions :tada:
 

packages/engine/Source/Scene/ClippingPlaneCollection.js

@@ -106,15 +106,15 @@ function ClippingPlaneCollection(options) {
    * An event triggered when a new clipping plane is added to the collection.  Event handlers
    * are passed the new plane and the index at which it was added.
    * @type {Event}
-   * @default Event()
+   * @readonly
    */
   this.planeAdded = new Event();
 
   /**
    * An event triggered when a new clipping plane is removed from the collection.  Event handlers
    * are passed the new plane and the index from which it was removed.
    * @type {Event}
-   * @default Event()
+   * @readonly
    */
   this.planeRemoved = new Event();
 
@@ -472,7 +472,7 @@ ClippingPlaneCollection.prototype.update = function (frameState) {
   // Compute texture requirements for current planes
   // In RGBA FLOAT, A plane is 4 floats packed to a RGBA.
   // In RGBA UNSIGNED_BYTE, A plane is a float in [0, 1) packed to RGBA and an Oct32 quantized normal,
-  // so 8 bits or 2 pixels in RGBA.
+  // so 8 bytes or 2 pixels in RGBA.
   const pixelsNeeded = useFloatTexture ? this.length : this.length * 2;
 
   if (defined(clippingPlanesTexture)) {