Static Tilemap Culling added

Author: bitnenfer

v3/src/camera/Camera.js

@@ -70,6 +70,7 @@ var Camera = new Class({
     centerToSize: require('./components/CenterToSize'),
     cull: require('./components/Cull'),
     cullHitTest: require('./components/CullHitTest'),
+    cullTilemap: require('./components/CullTilemap'),
     destroy: require('./components/Destroy'),
     fade: require('./components/Fade'),
     flash: require('./components/Flash'),

v3/src/camera/components/CullTilemap.js

@@ -0,0 +1,57 @@
+var CullTilemap = function (tilemap)
+{
+    var cameraMatrix = this.matrix.matrix;
+
+    var mva = cameraMatrix[0];
+    var mvb = cameraMatrix[1];
+    var mvc = cameraMatrix[2];
+    var mvd = cameraMatrix[3];
+    
+    /* First Invert Matrix */
+    var determinant = (mva * mvd) - (mvb * mvc);
+
+    if (!determinant)
+    {
+        return tiles;
+    }
+
+    var mve = cameraMatrix[4];
+    var mvf = cameraMatrix[5];
+    var tiles = tilemap.tiles;
+    var scrollX = this.scrollX;
+    var scrollY = this.scrollY;
+    var cameraW = this.width;
+    var cameraH = this.height;
+    var culledObjects = this.culledObjects;
+    var length = tiles.length;
+    var tileW = tilemap.tileWidth;
+    var tileH = tilemap.tileHeight;
+    var cullW = cameraW + tileW;
+    var cullH = cameraH + tileH;
+    var scrollFactorX = tilemap.scrollFactorX;
+    var scrollFactorY = tilemap.scrollFactorY;
+
+    determinant = 1 / determinant;
+
+    culledObjects.length = 0;
+
+    for (var index = 0; index < length; ++index)
+    {
+        var tile = tiles[index];
+        var tileX = (tile.x - (scrollX * scrollFactorX));
+        var tileY = (tile.y - (scrollY * scrollFactorY));
+        var tx = (tileX * mva + tileY * mvc + mve);
+        var ty = (tileX * mvb + tileY * mvd + mvf);
+        var tw = ((tileX + tileW) * mva + (tileY + tileH) * mvc + mve);
+        var th = ((tileX + tileW) * mvb + (tileY + tileH) * mvd + mvf);
+
+        if (tx > -tileW && ty > -tileH && tw < cullW && th < cullH)
+        {
+            culledObjects.push(tile);
+        }
+    }
+
+    return culledObjects;
+};
+
+module.exports = CullTilemap;

v3/src/gameobjects/tilemap/static/StaticTilemapCanvasRenderer.js

@@ -7,7 +7,7 @@ var StaticTilemapCanvasRenderer = function (renderer, gameObject, interpolationP
 
     gameObject.upload(camera);
 
-    var tiles = gameObject.tiles;
+    var tiles = camera.cullTilemap(gameObject);
     var tileWidth = gameObject.tileWidth;
     var tileHeight = gameObject.tileHeight;
     var frame = gameObject.frame;
@@ -16,6 +16,8 @@ var StaticTilemapCanvasRenderer = function (renderer, gameObject, interpolationP
     var image = frame.source.image;
     var tx = gameObject.x - camera.scrollX * gameObject.scrollFactorX;
     var ty = gameObject.y - camera.scrollY * gameObject.scrollFactorY;
+    var boundsX = camera.scrollX;
+
     ctx.save();
     ctx.translate(tx, ty);
     ctx.rotate(gameObject.rotation);