Added readme content

README.md

@@ -1,9 +1,63 @@
 # gemini-viewer-examples
 Examples and demos for gemini-viewer sdk
 
-# start
+# Set up the example project
 npm install
 
 npm start
 
-http://localhost:3000/#/demo
+http://localhost:3000/#/demo
+
+
+
+# gemini-viewer
+gemini-viewer is a WebGL based JS SDK, it is built on top of three.js. It provides following viewers:
+
+#### 1. BimViewer
+Used to view 3d BIM models. It supports formats including gltf, obj, fbx, ifc, dae, etc. Its features including measurement, section, display outline, orthographic camera, selection, etc.
+
+#### 2. DxfViewer
+Used to view 2d drawings. Only dxf format is supported, so user needs to convert dwg files to dxf. It supports most common entity types, it supports OLE and region via dwg2dxf; It supports common line types; It supports common hatch styles; It doesn't support line width;
+
+#### 3. VRViewer
+Used to view panoramas. It supports viewing a panorama with 1 image, 6 images, or 24 images; It supports viewing a serials of panoramas; It supports hotpoints;
+
+## Installation
+To install from npm:
+```
+npm install @pattern-x/gemini-viewer-threejs
+```
+
+## Examples for DxfViewer
+``` typescript
+import { DxfViewer, DxfViewerConfig, ModelConfig } from "@pattern-x/gemini-viewer-threejs";
+
+const viewerCfg: DxfViewerConfig = {
+    containerId: "myCanvas",
+    enableToolbar: true,
+    enableSpinner: true,
+    enableLayoutBar: true,
+};
+const modelCfg: ModelConfig = {
+    modelId: "id_0",
+    name: "sample",
+    src: "http://www.abc.com/sample.dxf",
+}
+const fontFiles = ["http://www.abc.com/hztxt.shx", "http://www.abc.com/simplex.shx"];
+const viewer = new DxfViewer(viewerCfg);
+await viewer.setFont(fontFiles);
+await viewer.loadModelAsync(modelCfg, (event) => {
+    const progress = (event.loaded * 100) / event.total;
+    console.log(`${event.type}: ${progress}%`);
+});
+console.log("Loaded");
+viewer.goToHomeView();
+```
+
+## Features for DxfViewer
+- Load and view dxf file
+- Distance measurement
+- Area measurement
+- Angle measurement
+- Markups
+- Undo/redo