Added culling sample.

samples/o3d-webgl/primitive.js

 /*
  * Copyright 2010, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 15 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 
 /**
  * A Primitive is a type of Element that is made from a list of points,
  * lines or triangles that use a single material.
- * 
+ *
  * @param opt_streamBank o3d.StreamBank The StreamBank used by this
  *     Primitive.
  * @constructor
  */
 o3d.Primitive = function(opt_streamBank) {
   o3d.Element.call(this);
   /**
    * The stream bank this primitive uses for vertices.
    * @type {o3d.StreamBank}
    */
@@ skipping 84 matching lines @@
         enabled_attribs.push(gl_index);
 
         // TODO(petersont): Change that hard-coded 4 down there.
         this.gl.vertexAttribPointer(
             gl_index, field.numComponents, this.gl.FLOAT, false,
             buffer.totalComponents * 4, field.offset_ * 4);
       }
     }
   }
 
+  this.gl.client.render_stats_['primitivesRendered'] += this.numberPrimitives;
+
   // TODO(petersont): Change the hard-coded 3 and triangles too.
   this.gl.bindBuffer(this.gl.ELEMENT_ARRAY_BUFFER, indexBuffer.gl_buffer_);
   this.gl.drawElements(this.gl.TRIANGLES,
                        this.numberPrimitives * 3,
                        this.gl.UNSIGNED_SHORT,
                        0);
 
   for (var i = 0; i < enabled_attribs.length; ++i) {
     this.gl.disableVertexAttribArray(enabled_attribs[i]);
   }
 };
+
+
+/**
+ * Computes the bounding box in same coordinate system as the specified
+ * POSITION stream.
+ * @param {number} position_stream_index Index of POSITION stream.
+ * @return {!o3d.BoundingBox}  The boundingbox for this element in local space.
+ */
+o3d.Primitive.prototype.getBoundingBox =
+    function(position_stream_index) {
+  var streamBank = this.streamBank;
+  var indexBuffer = this.indexBuffer;
+  var stream =
+    this.streamBank.vertexStreams[o3d.Stream.POSITION][position_stream_index];
+
+  var points = [];
+  var field = stream.field;
+  var buffer = field.buffer;
+  var numPoints = buffer.array_.length / buffer.totalComponents;
+
+  var elements = field.getAt(0, numPoints);
+
+  for (var index = 0; index < numPoints; ++index) {
+    var p = [0, 0, 0];
+    for (var i = 0; i < field.numComponents; ++i) {
+      p[i] = elements[field.numComponents * index + i];
+    }
+    points.push(p);
+  }
+
+  o3d.BoundingBox.fitBoxToPoints_(points, this.boundingBox);
+  return this.boundingBox;
+};
+
+
+