diff --git a/src/kiri/init.js b/src/kiri/init.js
index f989f780..535602bf 100644
--- a/src/kiri/init.js
+++ b/src/kiri/init.js
@@ -1619,11 +1619,11 @@
             fdmSep:              UC.newBlank({class:"pop-sep", modes:FDM}),
             sliceSupportSpan:    UC.newInput(LANG.sp_span_s, {title:LANG.sp_span_l, bound:UC.bound(0.0,200.0), convert:UC.toFloat, modes:FDM, show: () => UI.sliceSupportEnable.checked}),
             sliceSupportEnable:  UC.newBoolean(LANG.sp_auto_s, onBooleanClick, {title: LANG.sp_auto_l, modes:FDM, trigger:true}),
-            // sliceSupportGen:     UC.newRow([
-            //     UI.ssaGen = UC.newButton('detect', onButtonClick)
-            // ], { modes: FDM }),
 
             fdmSep:              UC.newBlank({class:"pop-sep", modes:FDM}),
+            sliceSupportGen:     LOCAL ? UC.newRow([
+                UI.ssaGen = UC.newButton('detect', onButtonClick, {class: "f-col grow a-center"})
+            ], { modes: FDM, class: "ext-buttons f-row grow" }) : null,
             sliceSupportManual: UC.newRow([
                 (UI.ssmAdd = UC.newButton(undefined, onButtonClick, {icon:'<i class="fas fa-plus"></i>'})),
                 (UI.ssmDun = UC.newButton(undefined, onButtonClick, {icon:'<i class="fas fa-check"></i>'})),
diff --git a/src/mode/cam/driver.js b/src/mode/cam/driver.js
index 8903f6f1..e0058c11 100644
--- a/src/mode/cam/driver.js
+++ b/src/mode/cam/driver.js
@@ -34,7 +34,6 @@
                     KIRI.codec.decode(output).forEach(rec => {
                         ids.push(rec.id);
                         widgets[rec.id].traces = rec.traces;
-                        // widgets[rec.id].sindex = rec.sindex;
                     });
                     ondone(ids);
                 });
@@ -45,11 +44,10 @@
                 const { settings } = data;
                 const widgets = Object.values(cache);
                 const fresh = widgets.filter(widget => CAM.traces(settings, widget));
-                send.done(KIRI.codec.encode(fresh.map(widget => {return {
+                send.done(KIRI.codec.encode(fresh.map(widget => { return {
                     id: widget.id,
                     traces: widget.traces,
-                    // sindex: widget.sindex
-                }})));
+                } } )));
             };
 
         });
diff --git a/src/mode/fdm/client.js b/src/mode/fdm/client.js
index 491202f3..48ac5b1e 100644
--- a/src/mode/fdm/client.js
+++ b/src/mode/fdm/client.js
@@ -50,8 +50,30 @@
         });
         api.event.on("fdm.supports.gen", func.sgen = () => {
             alert = api.show.alert("analyzing part...", 1000);
-            FDM.support_generate(done => {
+            FDM.support_generate(array => {
+                console.log({generated_supports: array});
                 api.hide.alert(alert);
+                for (let rec of array) {
+                    let { widget, supports } = rec;
+                    let wa = API.widgets.annotate(widget.id);
+                    let ws = wa.support || [];
+                    for (let support of supports) {
+                        let { from, to, mid } = support;
+                        let dw = api.conf.get().process.sliceSupportSize / 2;
+                        let dh = from.z - to.z;
+                        let rec = {
+                            x: mid.x,
+                            y: mid.y,
+                            z: mid.z,
+                            dw,
+                            dh,
+                            id: Math.random() * 0xffffffffff
+                        };
+                        addWidgetSupport(widget, rec);
+                        ws.push(Object.clone(rec));
+                    }
+                    wa.support = ws;
+                }
             });
         });
         api.event.on("fdm.supports.add", func.sadd = () => {
diff --git a/src/mode/fdm/driver.js b/src/mode/fdm/driver.js
index 6a2005a4..eccdea0e 100644
--- a/src/mode/fdm/driver.js
+++ b/src/mode/fdm/driver.js
@@ -39,12 +39,24 @@
         if (KIRI.client)
         // FDM.support_generate = KIRI.client.fdm_support_generate = function(ondone) {
         FDM.support_generate = function(ondone) {
-            send('fdm_support_generate', {}, ondone);
+            KIRI.client.sync();
+            let settings = API.conf.get();
+            let widgets = API.widgets.map();
+            send('fdm_support_generate', {}, (gen) => {
+                for (let g of gen) g.widget = widgets[g.id];
+                ondone(gen);
+            });
         };
 
         if (KIRI.worker)
         KIRI.worker.fdm_support_generate = function(data, send) {
-            send.done();
+            const { settings } = data;
+            const widgets = Object.values(cache);
+            const fresh = widgets.filter(widget => FDM.supports(settings, widget));
+            send.done(KIRI.codec.encode(fresh.map(widget => { return {
+                id: widget.id,
+                supports: widget.supports,
+            } } )));
         };
 
     });
diff --git a/src/mode/fdm/slice.js b/src/mode/fdm/slice.js
index ea6b5474..0d6e4aab 100644
--- a/src/mode/fdm/slice.js
+++ b/src/mode/fdm/slice.js
@@ -1074,4 +1074,36 @@
         return good.length > 2 ? good : [];
     }
 
+    FDM.supports = function(settings, widget) {
+        let buf = new THREE.BufferGeometry();
+        buf.setAttribute('position', new THREE.BufferAttribute(widget.vertices, 3));
+        let geo = new THREE.Geometry().fromBufferGeometry(buf);
+        // console.log('geo',
+        //     geo,
+        //     {
+        //         "<": geo.faces.filter(f => f.normal.z < 0),
+        //         ">": geo.faces.filter(f => f.normal.z > 0),
+        //         "=": geo.faces.filter(f => f.normal.z == 0)
+        //     }
+        // );
+        let mesh = new THREE.Mesh(geo, new THREE.MeshBasicMaterial());
+        let dir = new THREE.Vector3(0,0,-1)
+        let add = [];
+        geo.faces.filter(f => f.normal.z < 0).forEach(face => {
+            let a = geo.vertices[face.a];
+            let b = geo.vertices[face.b];
+            let c = geo.vertices[face.c];
+            let point = a.add(b).add(c).divideScalar(3);
+            let ray = new THREE.Raycaster(point, dir);
+            let int = ray.intersectObjects([ mesh ], false);
+            if (int && int.length) {
+                console.log(int);
+                let mid = new THREE.Vector3().add(point).add(int[0].point).divideScalar(2);
+                add.push({from: point, to: int[0].point, mid});
+            }
+        });
+        widget.supports = add;
+        return add.length > 0;
+    };
+
 })();