Experimental canvas vector layer renderer

2013-10-31 15:51:19 +01:00
parent 3a2133c130
commit 4b9642f4b1
1 changed files with 187 additions and 0 deletions
--- a/src/ol/renderer/canvas/canvasvectorlayerrenderer2.js
+++ b/src/ol/renderer/canvas/canvasvectorlayerrenderer2.js
@@ -0,0 +1,187 @@
+goog.provide('ol.renderer.canvas.VectorLayer2');
+
+goog.require('goog.dom');
+goog.require('goog.dom.TagName');
+goog.require('goog.vec.Mat4');
+goog.require('ol.ViewHint');
+goog.require('ol.extent');
+goog.require('ol.layer.Vector');
+goog.require('ol.renderer.canvas.Layer');
+goog.require('ol.renderer.canvas.Vector');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.renderer.canvas.Layer}
+ * @param {ol.renderer.Map} mapRenderer Map renderer.
+ * @param {ol.layer.Vector} layer Vector layer.
+ */
+ol.renderer.canvas.VectorLayer2 = function(mapRenderer, layer) {
+
+  goog.base(this, mapRenderer, layer);
+
+  /**
+   * Final canvas made available to the map renderer.
+   * @private
+   * @type {HTMLCanvasElement}
+   */
+  this.canvas_ = /** @type {HTMLCanvasElement} */
+      (goog.dom.createElement(goog.dom.TagName.CANVAS));
+
+  /**
+   * @private
+   * @type {!goog.vec.Mat4.Number}
+   */
+  this.coordsTransform_ = goog.vec.Mat4.createNumber();
+
+  /**
+   * @private
+   * @type {!goog.vec.Mat4.Number}
+   */
+  this.transform_ = goog.vec.Mat4.createNumber();
+
+  /**
+   * @private
+   * @type {number}
+   */
+  this.renderedResolution_ = 0;
+
+  /**
+   * @private
+   * @type {ol.Extent}
+   */
+  this.renderedExtent_ = null;
+
+  /**
+   * @private
+   * @type {function()}
+   */
+  this.requestMapRenderFrame_ = goog.bind(function() {
+    mapRenderer.getMap().requestRenderFrame();
+  }, this);
+
+};
+goog.inherits(ol.renderer.canvas.VectorLayer2, ol.renderer.canvas.Layer);
+
+
+/**
+ * @inheritDoc
+ */
+ol.renderer.canvas.VectorLayer2.prototype.getImage = function() {
+  return this.canvas_;
+};
+
+
+/**
+ * @return {ol.layer.Vector} Vector layer.
+ */
+ol.renderer.canvas.VectorLayer2.prototype.getVectorLayer = function() {
+  return /** @type {ol.layer.Vector} */ (this.getLayer());
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.renderer.canvas.VectorLayer2.prototype.getTransform = function() {
+  return this.transform_;
+};
+
+
+/**
+ * @param {ol.layer.VectorEvent} event Vector layer event.
+ * @private
+ */
+ol.renderer.canvas.VectorLayer2.prototype.handleLayerChange_ = function(event) {
+  this.requestMapRenderFrame_();
+};
+
+
+/**
+ * @inheritDoc
+ */
+ol.renderer.canvas.VectorLayer2.prototype.prepareFrame =
+    function(frameState, layerState) {
+
+  var extent = frameState.extent;
+  var view2DState = frameState.view2DState;
+  var viewCenter = view2DState.center;
+  var viewProjection = view2DState.projection;
+  var viewResolution = view2DState.resolution;
+  var viewRotation = view2DState.rotation;
+
+  var vectorLayer = this.getVectorLayer();
+
+  var hints = frameState.viewHints;
+
+  if (this.renderedResolution_ === 0 ||
+      (!hints[ol.ViewHint.ANIMATING] && !hints[ol.ViewHint.INTERACTING])) {
+
+    var features = vectorLayer.getFeaturesObjectForExtent(extent,
+        viewProjection, this.requestMapRenderFrame_);
+
+    if (goog.isNull(features)) {
+      return;
+    }
+
+    this.renderedResolution_ = viewResolution;
+    this.renderedExtent_ = extent;
+
+    var canvasWidth = ol.extent.getWidth(extent) / viewResolution;
+    var canvasHeight = ol.extent.getHeight(extent) / viewResolution;
+
+    var canvas = this.canvas_;
+    canvas.width = canvasWidth;
+    canvas.height = canvasHeight;
+
+    var halfWidth = canvasWidth;
+    var halfHeight = canvasHeight;
+
+    // transform for map coords to sketch canvas pixel coords
+    var coordsTransform = this.coordsTransform_;
+    var origin = ol.extent.getTopLeft(extent);
+    goog.vec.Mat4.makeIdentity(coordsTransform);
+    goog.vec.Mat4.translate(coordsTransform,
+        halfWidth, halfHeight, 0);
+    goog.vec.Mat4.scale(coordsTransform,
+        1 / viewResolution, -1 / viewResolution, 1);
+    goog.vec.Mat4.translate(coordsTransform,
+        -(origin[0] + halfWidth * viewResolution),
+        -(origin[1] - halfHeight * viewResolution),
+        0);
+    var renderer = new ol.renderer.canvas.Vector(canvas, coordsTransform,
+        this.requestMapRenderFrame_);
+
+    var groups = vectorLayer.groupFeaturesBySymbolizerLiteral(features,
+        viewResolution);
+
+    var i, ii, group, deferred;
+
+    ii = groups.length;
+    for (i = 0; i < ii; ++i) {
+      group = groups[i];
+      deferred = renderer.renderFeatures(group[0], group[1], group[2]);
+      if (deferred) {
+        break;
+      }
+    }
+  }
+
+  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,
+      this.renderedResolution_ / viewResolution,
+      this.renderedResolution_ / viewResolution,
+      1);
+  goog.vec.Mat4.rotateZ(transform, viewRotation);
+  goog.vec.Mat4.translate(transform,
+      (this.renderedExtent_[0] - viewCenter[0]) / this.renderedResolution_,
+      (viewCenter[1] - this.renderedExtent_[3]) / this.renderedResolution_,
+      0);
+
+};