move generate thumb

src/constants/saveConstants.js

@@ -1,4 +1,2 @@
-export const THUMBNAIL_WIDTH = 240 * 2; // multiply times 2 because retina
-export const THUMBNAIL_HEIGHT = 200 * 2;
 export const IMAGE_TYPE = 'image/jpeg';
 export const IMAGE_QUALITY = 1; // 0 - 1

src/utils/exportUtils.js

@@ -10,6 +10,8 @@ import { shapeToPoints } from '../shape/shapeToPoints.js';
 import { SHAPE_TYPE_PROPERTIES } from '../constants/shapeTypeProperties.js';
 import { LINE_WIDTH } from '../constants/exportConstants.js';
 import { bufferToBase64 } from '../utils/binaryUtils.js';
+import { IMAGE_TYPE, IMAGE_QUALIT } from 'doodle3d-core/constants/saveConstants.js';
+import createScene from '../d3/createScene.js';
 
 const THREE_BSP = ThreeBSP(THREE);
 
@@ -165,3 +167,34 @@ export async function createFile(state, type, options) {
       throw new Error(`did not regonize type ${type}`);
   }
 }
+
+export function generateThumb(state, responseType = 'blob', width = THUMBNAIL_WIDTH, height = THUMBNAIL_HEIGHT) {
+  return new Promise((resolve) => {
+    const { render, renderer, setSize } = createScene(state);
+
+    setSize(width, height, 1.0);
+    render();
+
+    // possible to add encoder options for smaller file setSize
+    // https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/toBlob
+    switch (responseType) {
+      case 'base64':
+        const base64 = renderer.domElement.toDataURL(IMAGE_TYPE, IMAGE_QUALITY);
+        resolve(base64);
+        break;
+
+      case 'objectURL':
+        renderer.domElement.toCanvas((blob) => {
+          const objectURL = URL.createObjectURL(blob);
+          resolve(objectURL);
+        }, IMAGE_TYPE, IMAGE_QUALITY);
+        break;
+
+      default:
+        renderer.domElement.toBlob((blob) => {
+          resolve(blob);
+        }, IMAGE_TYPE, IMAGE_QUALITY);
+        break;
+    }
+  });
+}