refactor: simpification & semantics

packages/topdown/index.js

@@ -1,3 +1,3 @@
-export {TilesView} from './tiles-view';
+export {TilesRenderer} from './tiles-renderer';
 export {Tiles} from './tiles';
 export {Tileset} from './tileset';

packages/topdown/tiles-renderer.js

@@ -0,0 +1,50 @@
+import {Canvas, Container, Sprite} from '@avocado/graphics';
+import {Rectangle, Vector} from '@avocado/math';
+
+export class TilesRenderer {
+
+  constructor(tiles, tileset) {
+    this.tiles = tiles;
+    this.tileset = tileset;
+  }
+
+  renderChunk(renderer, rectangle) {
+    // No rectangle? Render all.
+    if (!rectangle) {
+      rectangle = Rectangle.compose([0, 0], this.tiles.size);
+    }
+    const slice = this.tiles.slice(rectangle);
+    if (!slice) {
+      return undefined;
+    }
+    // Precalcs.
+    const size = Rectangle.size(rectangle);
+    const tileSize = this.tileset.tileSize;
+    const rowWidth = size[0] * tileSize[0];
+    // Render all tiles.
+    const container = new Container();
+    const position = [0, 0];
+    for (let i = 0; i < slice.length; ++i) {
+      const index = slice[i];
+      const sprite = new Sprite(this.tileset.subimages[index]);
+      sprite.position = position;
+      container.addChild(sprite);
+      // Only adds, please.
+      position[0] += tileSize[0];
+      if (rowWidth === position[0]) {
+        position[0] = 0;
+        position[1] += tileSize[1];
+      }
+    }
+    // Blit to canvas.
+    const canvasSize = Vector.mul(size, tileSize);
+    const canvas = new Canvas(canvasSize);
+    canvas.renderWith(container, renderer);
+    container.destroy();
+    // Convert to image and return.
+    const image = canvas.toImage();
+    canvas.destroy();
+    return image;
+  }
+
+}

packages/topdown/tiles-view.js

@@ -1,72 +0,0 @@
-import {compose} from '@avocado/core';
-import {Canvas, Container, Renderable, Sprite} from '@avocado/graphics';
-import {Vector} from '@avocado/math';
-
-export class TilesView extends Renderable {
-
-  constructor(tiles, tileset) {
-    super();
-    this.tiles = tiles;
-    this.tileset = tileset;
-    this.canvas = new Canvas();
-    this.sprite = undefined;
-  }
-
-  destroy() {
-    this.container.destroy();
-  }
-
-  indexMapFromSlice(slice) {
-    const indexes = new Map();
-    for (const i in slice) {
-      const tile = slice[i];
-      if (!indexes.get(tile)) {
-        indexes.set(tile, new Set());
-      }
-      indexes.get(tile).add(parseInt(i));
-    }
-    return indexes;
-  }
-
-  get internal() {
-    return this.canvas.internal;
-  }
-
-  renderWith(renderer) {
-    const size = this.tiles.size;
-    const tileSize = Vector.mul(this.tileset.tileSize, this.scale);
-    const rowWidth = size[0] * tileSize[0];
-    const canvasSize = Vector.mul(size, tileSize);
-    this.canvas.size = canvasSize;
-    const slice = this.tiles.slice([0, 0, size[0], size[1]]);
-    const indexMap = this.indexMapFromSlice(slice);
-    const container = new Container();
-    for (const [tile, indexes] of indexMap.entries()) {
-      let iterator = indexes.values();
-      let result = iterator.next();
-      while (!result.done) {
-        const position = [0, 0];
-        const validIndex = result.value;
-        for (const indexString in slice) {
-          const index = parseInt(indexString);
-          if (index === validIndex) {
-            const sprite = new Sprite(this.tileset.subimages[tile]);
-            sprite.scale = this.scale;
-            sprite.position = position;
-            container.addChild(sprite);
-          }
-          position[0] += tileSize[0];
-          if (rowWidth === position[0]) {
-            position[1] += tileSize[1];
-            position[0] = 0;
-          }
-        }
-        result = iterator.next();
-      }
-    }
-    this.canvas.renderWith(container, renderer);
-    container.destroy();
-    return this.canvas.toImage();
-  }
-
-}