fix(volume shader): fix light sphere bound, decrease anisotropy threashold, spelling

Author: JiayiXuu

Examples/Volume/VolumeMapperLightAndShadow/controller.html

@@ -21,9 +21,9 @@
         </td>
     </tr>
     <tr>
-        <td>Anistropy</td>
+        <td>Anisotropy</td>
         <td>
-        <input class='anistropy' type="range" min="-1.0" max="1.0" step="0.1" value="0.0" />
+        <input class='anisotropy' type="range" min="-1.0" max="1.0" step="0.05" value="0.0" />
         </td>
     </tr>      
 </table>     

Examples/Volume/VolumeMapperLightAndShadow/index.js

@@ -228,7 +228,7 @@ function createVolumeShadowViewer(rootContainer, fileContents) {
   sd.setAttribute('max', 10);
   sd.setAttribute('value', 5);
   sd.addEventListener('input', updateSD);
-  const at = document.querySelector('.anistropy');
+  const at = document.querySelector('.anisotropy');
   at.setAttribute('min', -1.0);
   at.setAttribute('max', 1.0);
   at.setAttribute('value', 0.0);
@@ -257,19 +257,12 @@ function createVolumeShadowViewer(rootContainer, fileContents) {
     actorSphere.getProperty().setColor([1, 0, 0]);
     actorSphere.getProperty().setLighting(false);
     actorSphere.setMapper(mapperSphere);
+    actorSphere.setUseBounds(false);
     renderer.addActor(actorSphere);
   }
 
   // Camera and first render
   renderer.resetCamera();
-  renderer
-    .getActiveCamera()
-    .setFocalPoint(center[0] - 300, center[1] + 120, center[2] + 100);
-  renderer.getActiveCamera().setClippingRange([300, 1800]);
-  renderer
-    .getActiveCamera()
-    .setPosition(center[0] + 650, center[1] + 10, center[2] - 200);
-  renderer.getActiveCamera().setViewUp(0, 0, -1);
   renderWindow.render();
 
   // Make some variables global so that you can inspect and

Sources/Rendering/Core/VolumeMapper/index.js

@@ -84,7 +84,7 @@ function vtkVolumeMapper(publicAPI, model) {
     publicAPI.modified();
   };
 
-  publicAPI.setVlumeShadowSamplingDistFactor = (vsdf) => {
+  publicAPI.setVolumeShadowSamplingDistFactor = (vsdf) => {
     model.volumeShadowSamplingDistFactor = vsdf >= 1.0 ? vsdf : 1.0;
     publicAPI.modified();
   };
@@ -112,8 +112,8 @@ const DEFAULT_VALUES = {
   preferSizeOverAccuracy: false, // Whether to use halfFloat representation of float, when it is inaccurate
   computeNormalFromOpacity: false,
   // volume shadow parameters
-  globalIlluminationReach: 0.0,
   volumetricScatteringBlending: 0.0,
+  globalIlluminationReach: 0.0,
   volumeShadowSamplingDistFactor: 5.0,
   anisotropy: 0.0,
 };
@@ -134,8 +134,8 @@ export function extend(publicAPI, model, initialValues = {}) {
     'filterMode',
     'preferSizeOverAccuracy',
     'computeNormalFromOpacity',
-    'globalIlluminationReach',
     'volumetricScatteringBlending',
+    'globalIlluminationReach',
     'volumeShadowSamplingDistFactor',
     'anisotropy',
   ]);

Sources/Rendering/OpenGL/glsl/vtkVolumeFS.glsl

@@ -727,7 +727,7 @@ vec3 applyShadowRay(vec3 tColor, vec3 posIS, vec3 viewDirectionVC)
     float dDotL = dot(viewDirectionVC, normalize(vertLight));
     // isotropic scatter returns 0.5 instead of 1/4pi to increase intensity
     float phase_attenuation = 0.5;
-    if (abs(anisotropy) > 0.01){
+    if (abs(anisotropy) > EPSILON){
       phase_attenuation = phase_function(dDotL);
     }
     float vol_shadow = volume_shadow(posIS, normalize(rotateToIDX(vertLight)));