add 'z thru' option for cleaner cutouts

src/kiri/conf.js

@@ -444,6 +444,7 @@
                     camZTopOffset: 0,
                     camZBottom: 0,
                     camZClearance: 1,
+                    camZThru: 0,
                     camFastFeed: 6000,
                     camFastFeedZ: 300,
                     camTolerance: 0.15,

src/kiri/init.js

@@ -1449,6 +1449,7 @@
             camZTopOffset:       UC.newInput(LANG.ou_ztof_s, {title:LANG.ou_ztof_l, convert:UC.toFloat, modes:CAM}),
             camZBottom:          UC.newInput(LANG.ou_zbot_s, {title:LANG.ou_zbot_l, convert:UC.toFloat, modes:CAM}),
             camZClearance:       UC.newInput(LANG.ou_zclr_s, {title:LANG.ou_zclr_l, convert:UC.toFloat, bound:UC.bound(0.01,100), modes:CAM}),
+            camZThru:            UC.newInput(LANG.ou_ztru_s, {title:LANG.ou_ztru_l, convert:UC.toFloat, bound:UC.bound(0.0,100), modes:CAM}),
             camFastFeedZ:        UC.newInput(LANG.cc_rzpd_s, {title:LANG.cc_rzpd_l, convert:UC.toInt, modes:CAM}),
             camFastFeed:         UC.newInput(LANG.cc_rapd_s, {title:LANG.cc_rapd_l, convert:UC.toInt, modes:CAM}),
             camTolerance:        UC.newInput(LANG.ou_toll_s, {title:LANG.ou_toll_l, convert:UC.toFloat, bound:UC.bound(0.001,1.0), modes:CAM}),

src/mode/cam/driver.js

@@ -882,6 +882,7 @@
             bounds = widget.getBoundingBox(),
             mesh = widget.mesh,
             zMin = Math.max(bounds.min.z, proc.camZBottom) * units,
+            zThru = (proc.camZThru || 0) * units,
             camRoughStock = proc.camRoughStock * units,
             shellRough,
             shellOutline,
@@ -986,6 +987,18 @@
             slice.tops[0].traces = nutrace;
         }
 
+        // extend bottom cutout
+        const addZThru = function(selected) {
+            let last = selected[selected.length-1];
+            let add = last.clone(true);
+            add.camMode = last.camMode;
+            add.z -= zThru;
+            add.tops.forEach(top => {
+                top.poly.setZ(add.z);
+            });
+            selected.push(add);
+        };
+
         // called when z-index slicing complete
         const camSlicesDone = function(slices) {
 
@@ -1049,6 +1062,9 @@
             if (procRough) {
                 let selected = [];
                 selectSlices(slices, proc.camRoughDown * units, CPRO.ROUGH, selected);
+                if (zThru) {
+                    addZThru(selected);
+                }
                 sliceAll.appendAll(selected);
                 if (!proc.camRoughVoid) {
                     thruHoles = holes(slices, roughToolDiam + camRoughStock);
@@ -1058,6 +1074,9 @@
             if (procOutline) {
                 let selected = [];
                 selectSlices(slices, proc.camOutlineDown * units, CPRO.OUTLINE, selected);
+                if (zThru) {
+                    addZThru(selected);
+                }
                 sliceAll.appendAll(selected);
             }
         }

web/kiri/lang/en.js

@@ -353,6 +353,8 @@ kiri.lang['en-us'] = {
     ou_zbot_l:      "offset from part bottom\nto limit cutting depth\nin workspace units",
     ou_zclr_s:      "z clearance",
     ou_zclr_l:      "travel offset from z top\nin workspace units",
+    ou_ztru_s:      "z thru",
+    ou_ztru_l:      "extend cutout pass down\nin workspace units",
     ou_conv_s:      "conventional",
     ou_conv_l:      "milling direction\nuncheck for 'climb'",
     ou_depf_s:      "depth first",