From fb7ccc9d1687c14cf4e3bbc61a41e7ebdd4cac99 Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Thu, 7 Nov 2013 15:06:35 +0100
Subject: [PATCH] Add initial canvas vector layer renderer

---
 .../canvas/canvasvectorlayerrenderer.js       | 137 ++++++++++++++++++
 1 file changed, 137 insertions(+)
 create mode 100644 src/ol/renderer/canvas/canvasvectorlayerrenderer.js

diff --git a/src/ol/renderer/canvas/canvasvectorlayerrenderer.js b/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
new file mode 100644
index 0000000000..3ed41c9a4d
--- /dev/null
+++ b/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
@@ -0,0 +1,137 @@
+goog.provide('ol.renderer.canvas.VectorLayer');
+
+goog.require('goog.vec.Mat4');
+goog.require('ol.extent');
+goog.require('ol.renderer.canvas.Layer');
+goog.require('ol.renderer.vector');
+goog.require('ol.replay.canvas.BatchGroup');
+goog.require('ol.style.DefaultStyleFunction');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.renderer.canvas.Layer}
+ * @param {ol.renderer.Map} mapRenderer Map renderer.
+ * @param {ol.layer.Vector} vectorLayer Vector layer.
+ */
+ol.renderer.canvas.VectorLayer = function(mapRenderer, vectorLayer) {
+
+  goog.base(this, mapRenderer, vectorLayer);
+
+  /**
+   * @private
+   * @type {!goog.vec.Mat4.Number}
+   */
+  this.transform_ = goog.vec.Mat4.createNumber();
+
+  /**
+   * @private
+   * @type {number}
+   */
+  this.renderedRevision_ = -1;
+
+  /**
+   * @private
+   * @type {number}
+   */
+  this.renderedResolution_ = NaN;
+
+  /**
+   * @private
+   * @type {ol.Extent}
+   */
+  this.renderedExtent_ = ol.extent.createEmpty();
+
+  /**
+   * @private
+   * @type {ol.replay.canvas.BatchGroup}
+   */
+  this.batchGroup_ = null;
+
+};
+goog.inherits(ol.renderer.canvas.VectorLayer, ol.renderer.canvas.Layer);
+
+
+/**
+ * @inheritDoc
+ */
+ol.renderer.canvas.VectorLayer.prototype.composeFrame =
+    function(frameState, layerState, context) {
+
+  var batchGroup = this.batchGroup_;
+  if (goog.isNull(batchGroup)) {
+    return;
+  }
+
+  var view2DState = frameState.view2DState;
+  var viewCenter = view2DState.center;
+  var viewResolution = view2DState.resolution;
+  var viewRotation = view2DState.rotation;
+
+  var transform = this.transform_;
+  goog.vec.Mat4.makeIdentity(transform);
+  goog.vec.Mat4.translate(transform,
+      frameState.size[0] / 2,
+      frameState.size[1] / 2,
+      0);
+  goog.vec.Mat4.scale(transform,
+      1 / viewResolution,
+      -1 / viewResolution,
+      1);
+  goog.vec.Mat4.rotateZ(transform, -viewRotation);
+  goog.vec.Mat4.translate(transform,
+      -viewCenter[0],
+      -viewCenter[1],
+      0);
+
+  batchGroup.draw(context, transform);
+
+};
+
+
+/**
+ * @return {ol.layer.Vector} Vector layer.
+ */
+ol.renderer.canvas.VectorLayer.prototype.getVectorLayer = function() {
+  return /** @type {ol.layer.Vector} */ (this.getLayer());
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.renderer.canvas.VectorLayer.prototype.prepareFrame =
+    function(frameState, layerState) {
+
+  var vectorLayer = this.getVectorLayer();
+  var vectorSource = vectorLayer.getVectorSource();
+
+  if (this.renderedResolution_ == frameState.view2DState.resolution &&
+      this.renderedRevision_ == vectorSource.getRevision() &&
+      ol.extent.containsExtent(this.renderedExtent_, frameState.extent)) {
+    return;
+  }
+
+  // FIXME dispose of old batchGroup in post render
+  goog.dispose(this.batchGroup_);
+  this.batchGroup = null;
+
+  var styleFunction = vectorLayer.getStyleFunction();
+  if (!goog.isDef(styleFunction)) {
+    styleFunction = ol.style.DefaultStyleFunction;
+  }
+  var batchGroup = new ol.replay.canvas.BatchGroup();
+  vectorSource.forEachFeatureInExtent(frameState.extent, function(feature) {
+    var style = styleFunction(feature);
+    ol.renderer.vector.renderFeature(batchGroup, feature, style);
+  }, this);
+
+  this.renderedResolution_ = frameState.view2DState.resolution;
+  this.renderedRevision_ = vectorSource.getRevision();
+  this.renderedExtent_ = frameState.extent;
+  if (!batchGroup.isEmpty()) {
+    this.batchGroup_ = batchGroup;
+  }
+
+};