fix transformPlane indexed

Author: ngokevin

index.js

@@ -437,8 +437,9 @@ const tri = (function () {
  * Faces of a plane are v0, v2, v1 and v2, v3, v1.
  * Positions are 12 numbers: [v0, v1, v2, v3].
  */
-function transformPlane(index, geometry, originalArray, position, rotation) {
+function transformPlane(particleIndex, geometry, originalArray, position, rotation) {
   const array = geometry.attributes.position.array;
+  const index = particleIndex * NUM_PLANE_POSITIONS;
 
   // Calculate first face (0, 2, 1).
   tri.vertices[0].set(

tests/index.test.js

@@ -108,19 +108,19 @@ suite('particle player', function () {
       component._transformPlane(1, geometry, originalPositions,
                                new THREE.Vector3(1.1, 2.2, 3.3));
       for (let i = 12; i < 24; i += 3) {
-        positions[i] = originalPositions[i] + 1.1;
-        positions[i + 1] = originalPositions[i + 1] + 2.2;
-        positions[i + 2] = originalPositions[i + 2] + 3.3;
+        assertAlmostEqual(positions[i], originalPositions[i] + 1.1);
+        assertAlmostEqual(positions[i + 1], originalPositions[i + 1] + 2.2);
+        assertAlmostEqual(positions[i + 2], originalPositions[i + 2] + 3.3);
       }
       for (let i = 0; i < 12; i += 3) {
-        positions[i] = originalPositions[i];
-        positions[i + 1] = originalPositions[i + 1];
-        positions[i + 2] = originalPositions[i + 2];
+        assertAlmostEqual(positions[i], originalPositions[i]);
+        assertAlmostEqual(positions[i + 1], originalPositions[i + 1]);
+        assertAlmostEqual(positions[i + 2], originalPositions[i + 2]);
       }
       for (let i = 24; i < 36; i += 3) {
-        positions[i] = originalPositions[i];
-        positions[i + 1] = originalPositions[i + 1];
-        positions[i + 2] = originalPositions[i + 2];
+        assertAlmostEqual(positions[i], originalPositions[i]);
+        assertAlmostEqual(positions[i + 1], originalPositions[i + 1]);
+        assertAlmostEqual(positions[i + 2], originalPositions[i + 2]);
       }
     });
 
@@ -172,3 +172,7 @@ function assertAlmostArray(x, y) {
   y = x.map(n => n.toFixed(4));
   assert.shallowDeepEqual(x, y);
 }
+
+function assertAlmostEqual(x, y) {
+  assert.equal(x.toFixed(4), y.toFixed(4));
+}