Change resolutions xs+, sm, sm+

docs/api/camera-source.md

 **Arguments**
 
 * `settings: object, optional`. An object with the following keys (all are optional):
-    * `resolution: Resolution`. The desired [resolution](resolution.md) of the video. The higher the resolution, the longer it takes for the video to be uploaded to the GPU, which impacts performance. The lower the resolution, the less accurate the tracking will be. Suggested values: `"md+"`, `"md"`, `"sm+"`.
+    * `resolution: Resolution`. The desired [resolution](resolution.md) of the video. The higher the resolution, the longer it takes for the video to be uploaded to the GPU, which impacts performance. The lower the resolution, the less accurate the tracking will be. Suggested values: `"md+"`, `"md"`, `"sm+"`, `"sm"`.
     * `aspectRatio: number`. A hint specifying the preferred aspect ratio of the video.
     * `constraints: MediaTrackConstraints`. Additional video constraints that will be passed to `navigator.mediaDevices.getUserMedia()`.
 

docs/api/resolution.md

 # Resolution
 
-A `Resolution` is a setting defined by a string. It is mapped to a size measured in pixels according to special rules. You may use it, for example, to change the resolution of a video captured by a webcam, to adjust the resolution of a video when it is processed by a tracker, or to set the resolution of the virtual scene when it is rendered.
+A `Resolution` is a setting defined by a string. It is mapped to a size measured in pixels according to special rules. You may use it, for example, to change the resolution of a video captured by a webcam, to adjust the resolution of a video when it is processed by a tracker, or to set the rendering resolution of a virtual scene.
 
 The table below shows examples of how resolution strings are converted to pixels:
 
-| Resolution | 16:9 landscape | 16:10 landscape | 4:3 landscape | Notes |
-| ---------- | -------------- | --------------- | ------------- | ----- |
+| Resolution | 16:9 | 16:10 | 4:3 | Notes |
+| ---------- | ---- | ----- | --- | ----- |
 | `"xs"` | 214x120 | 192x120 | 160x120 | |
-| `"xs+"` | 284x160 | 256x160 | 214x160 | |
-| `"sm"` | 356x200 | 320x200 | 266x200 | |
-| `"sm+"` | 426x240 | 384x240 | 320x240 | 240p |
+| `"xs+"` | 256x144 | 230x144 | 192x144 | 144p |
+| `"sm"` | 426x240 | 384x240 | 320x240 | 240p |
+| `"sm+"` | 512x288 | 460x288 | 384x288 | |
 | `"md"` | 568x320 | 512x320 | 426x320 | |
 | `"md+"` | 640x360 | 576x360 | 480x360 | 360p |
 | `"lg"` | 854x480 | 768x480 | 640x480 | 480p |
 | `"xl"` | 1280x720 | 1152x720 | 960x720 | 720p |
 | `"xl+"` | 1366x768 | 1228x768 | 1024x768 | |
 | `"xxl"` | 1600x900 | 1440x900 | 1200x900 | |
-| `"xxl+"` | 1706x960 | 1536x960 | 1280x960 | 960p |
+| `"xxl+"` | 1706x960 | 1536x960 | 1280x960 | |

plugins/aframe-with-encantar.js

     schema: {
 
         /** resolution of the tracker: "xs" | "xs+" | "sm" | "sm+" | "md" | "md+" | "lg" | "lg+" | "xl" | "xl+" | "xxl" | "xxl+" */
-        'resolution': { type: 'string', default: 'sm+' },
+        'resolution': { type: 'string', default: 'sm' },
 
     },
 

src/sources/camera-source.ts

 
 /** Default options for camera sources */
 const DEFAULT_CAMERA_OPTIONS: Readonly<Required<CameraSourceOptions>> = {
-    resolution: 'md', //'sm+',
+    resolution: 'md',
     aspectRatio: 16/9,
     constraints: { facingMode: 'environment' },
 };

src/trackers/image-tracker/settings.ts

  */
 
 /** Default tracking resolution */
-export const DEFAULT_TRACKING_RESOLUTION = 'sm+';
+export const DEFAULT_TRACKING_RESOLUTION = 'sm';
 
 /** Maximum number of keypoints to be stored for each reference image when in the training state */
 export const TRAIN_MAX_KEYPOINTS = 1024; //512;

src/utils/resolution.ts

 /** Reference heights when in landscape mode, measured in pixels */
 const REFERENCE_HEIGHT: { readonly [R in Resolution]: number } = {
     'xs' : 120,
-    'xs+': 160,
-    'sm' : 200,
-    'sm+': 240,
+    'xs+': 144,
+    'sm' : 240,
+    'sm+': 288,
     'md' : 320,
     'md+': 360,
     'lg' : 480,
     'lg+': 600,
-    'xl' : 720, // should we define an alias, "hd"?
+    'xl' : 720,
     'xl+': 768,
     'xxl': 900,
     'xxl+':960,
     //'ul-': 1024,
     //'ul': 1080, // what should we call this? xxxl? ul? (ultra large?)
     //'ul+': 1200,
+    // instead of defining xxxl, what if we accept custom resolution names such as "720p" and "1080p"?
 };
 
 /**