Added fitView option to SVG export

Author: jmwright

cadquery/occ_impl/exporters/svg.py

@@ -180,6 +180,7 @@ def getSVG(shape, opts=None):
     hiddenColor = tuple(d["hiddenColor"])
     showHidden = bool(d["showHidden"])
     focus = float(d["focus"]) if d.get("focus") else None
+    fitView = bool(d["fitView"]) if d.get("fitView") else None
 
     hlr = HLRBRep_Algo()
     hlr.Add(shape.wrapped)
@@ -235,8 +236,15 @@ def getSVG(shape, opts=None):
     # get bounding box -- these are all in 2D space
     bb = Compound.makeCompound(hidden + visible).BoundingBox()
 
+    # Determine whether the user wants to fit the drawing to the bounding box
+    bb_scale = 0.75
+    if fitView:
+        bb_scale = 1.0
+        width = bb.xlen
+        height = bb.ylen
+
     # width pixels for x, height pixels for y
-    unitScale = min(width / bb.xlen * 0.75, height / bb.ylen * 0.75)
+    unitScale = min(width / bb.xlen * bb_scale, height / bb.ylen * bb_scale)
 
     # compute amount to translate-- move the top left into view
     (xTranslate, yTranslate) = (

doc/importexport.rst

@@ -216,6 +216,7 @@ options are as follows.
 * *hiddenColor* - Color of the line that hidden edges are drawn with.
 * *showHidden* - Whether or not to show hidden lines.
 * *focus* - If specified, creates a perspective SVG with the projector at the distance specified.
+* *fitView* - If specified, will attempt to fit the height and width of the image to the contents. The ``marginLeft`` and ``marginTop`` options should be set to 0 or the object will fall outside the viewport. The ``width`` and ``height`` options that were specified will be overridden, which can cause unexpected final image sizes.
 
 The options are passed to the exporter in a dictionary, and can be left out to force the SVG to be created with default options. 
 Below are examples with and without options set.

tests/test_exporters.py

@@ -562,6 +562,7 @@ def testSVGOptions(self):
                 "hiddenColor": (0, 0, 255),
                 "showHidden": True,
                 "focus": 4,
+                "fitView": True,
             },
         )