add stylus and touch mode to drawing a shape

src/ol/events/condition.js

@@ -230,6 +230,19 @@ export const mouseOnly = function(mapBrowserEvent) {
   return pointerEvent.pointerType == 'mouse';
 };
 
+export const touchOnly = (mapBrowserEvent) => {
+  const pointerEvt = /** @type {import("../MapBrowserPointerEvent").default} */ (mapBrowserEvent).pointerEvent;
+  assert(pointerEvt !== undefined, 56); // mapBrowserEvent must originate from a pointer event
+  // see http://www.w3.org/TR/pointerevents/#widl-PointerEvent-pointerType
+  return pointerEvt.pointerType === 'touch';
+};
+
+export const penOnly = (mapBrowserEvent) => {
+  const pointerEvt = /** @type {import("../MapBrowserPointerEvent").default} */ (mapBrowserEvent).pointerEvent;
+  assert(pointerEvt !== undefined, 56); // mapBrowserEvent must originate from a pointer event
+  // see http://www.w3.org/TR/pointerevents/#widl-PointerEvent-pointerType
+  return pointerEvt.pointerType === 'pen';
+};
 
 /**
  * Return `true` if the event originates from a primary pointer in

src/ol/interaction/Draw.js

@@ -528,7 +528,7 @@ class Draw extends PointerInteraction {
   handleDownEvent(event) {
     this.shouldHandle_ = !this.freehand_;
 
-    if (this.freehand_) {
+    if (this.freehand_ && ((this.condition_ && this.condition_(event)) || true)) {
       this.downPx_ = event.pixel;
       if (!this.finishCoordinate_) {
         this.startDrawing_(event);
@@ -548,7 +548,6 @@ class Draw extends PointerInteraction {
     }
   }
 
-
   /**
    * @inheritDoc
    */