Bbox enhancements for adjuster extension

extensions/fablabchemnitz/epilog_bbox_adjust/epilog_bbox_adjust.inx

@@ -2,14 +2,24 @@
 <inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
 	<name>Epilog Dashboard BBox Adjust</name>
 	<id>fablabchemnitz.de.epilog_bbox_adjust</id>
-	<effect needs-document="true" needs-live-preview="false">
+    <param name="offset" type="float" min="0.0" max="1000.0" precision="3" gui-text="XY Offset (mm) from top left corner">1.0</param>
+    <param name="use_machine_size" type="bool" gui-text="Use machine size (else use symmetric border)">false</param>
+    <param name="machine_size" gui-text="Machine/Size" type="optiongroup" appearance="combo">
+        <option value="406x305">406 x 305 mm (Zing 16)</option>
+        <option value="610x305">610 x 305 mm (Zing 24 / Fusion Edge 12)</option>    
+        <option value="812x508">812 x 508 mm (Fusion Pro 32 / Fusion M2 32)</option>
+        <option value="1016x711">1016 x 711 (Fusion M2 40)</option>
+        <option value="1219x914">1219 x 914 mm (Fusion Pro 48)</option>
+    </param>
+    <label>Widen the document to send all lines properly to Epilog Dashboard</label>
+	<effect needs-document="true" needs-live-preview="true">
 		<object-type>all</object-type>
 		<effects-menu>
             <submenu name="FabLab Chemnitz">
 				<submenu name="Various"/>
             </submenu>
 		</effects-menu>
-        <menu-tip>Widen the document to send all lines properly to Epilog Dashboard (adds 1.0 doc units of extra offset)</menu-tip>
+        <menu-tip>Widen the document to send all lines properly to Epilog Dashboard</menu-tip>
 	</effect>
 	<script>
 		<command location="inx" interpreter="python">epilog_bbox_adjust.py</command>

extensions/fablabchemnitz/epilog_bbox_adjust/epilog_bbox_adjust.py

@@ -10,17 +10,29 @@ So we add a default (small) amount of 1.0 doc units to expand the document's can
 Author: Mario Voigt / FabLab Chemnitz
 Mail: mario.voigt@stadtfabrikanten.org
 Date: 21.04.2021
-Last patch: 21.04.2021
+Last patch: 23.05.2021
 License: GNU GPL v3
+
+#known bugs:
+- viewbox/width/height do not correctly apply if documents only contain an object (not a path). After converting it to path it works. Seems to be a bbox problem
+- note from 07.05.2021: seems if the following order is viewBox/width/height, or width/height/viewBox, the units are not respected. So me mess around a little bit
 '''
 
+import math
 import inkex
 from inkex import Transform
 
 class BBoxAdjust(inkex.EffectExtension):
 
+    def add_arguments(self, pars):
+        pars.add_argument("--offset", type=float, default="1.0", help="XY Offset (mm) from top left corner")
+        pars.add_argument("--use_machine_size", type=inkex.Boolean, default=False, help="Use machine size")
+        pars.add_argument("--machine_size", default="812x508", help="Machine/Size")
+
     def effect(self):
-        offset = 1.0 #in documents' units
+        offset = self.options.offset
+        #units = self.svg.unit
+        units = "mm" #force millimeters
 
         # create a new bounding box and get the bbox size of all elements of the document (we cannot use the page's bbox)
         bbox = inkex.BoundingBox()
@@ -28,12 +40,21 @@ class BBoxAdjust(inkex.EffectExtension):
             if isinstance (element, inkex.ShapeElement):
                 bbox += element.bounding_box()
 
-        # adjust the viewBox to the bbox size and add the desired offset
+        if abs(bbox.width) == math.inf or abs(bbox.height) == math.inf:
-        # note from 07.05.2021: seems if the following order is viewBox/width/height, or width/height/viewBox, the units are not respected. So me mess around a little bit
+            inkex.utils.debug("Error calculating bounding box!")
-        self.document.getroot().attrib['width'] = f'{bbox.width + offset * 2}' + self.svg.unit
+            return
-        self.document.getroot().attrib['viewBox'] = f'{-offset} {-offset} {bbox.width + offset * 2} {bbox.height + offset * 2}'
-        self.document.getroot().attrib['height'] = f'{bbox.height + offset * 2}' + self.svg.unit
 
+    # adjust the viewBox to the bbox size and add the desired offset
+        if self.options.use_machine_size is True:
+            machineHeight = float(self.options.machine_size.split('x')[0])
+            machineWidth = float(self.options.machine_size.split('x')[1])
+            self.document.getroot().attrib['width'] = f'{machineHeight}' + units
+            self.document.getroot().attrib['viewBox'] = f'{-offset} {-offset} {machineHeight} {machineWidth}'     
+            self.document.getroot().attrib['height'] = f'{machineWidth}' + units
+        else:
+            self.document.getroot().attrib['width'] = f'{bbox.width + offset * 2}' + units
+            self.document.getroot().attrib['viewBox'] = f'{-offset} {-offset} {bbox.width + offset * 2} {bbox.height + offset * 2}'
+            self.document.getroot().attrib['height'] = f'{bbox.height + offset * 2}' + units
         # translate all elements to fit the adjusted viewBox
         mat = Transform("translate(%f, %f)" % (-bbox.left,-bbox.top)).matrix
         for element in self.svg.root.getchildren():