Merge pull request #106 from CadQuery/adam-urbanczyk-text-rendering

Support for text rendering

cadquery/cq.py

@@ -2268,6 +2268,20 @@ class Workplane(CQ):
             r = baseSolid.fuse(obj)
 
         return self.newObject([r])
+      
+    def _cutFromBase(self, obj):
+        """
+        Cuts the provided object from the base solid, if one can be found.
+        :param obj:
+        :return: a new object that represents the result of combining the base object with obj,
+           or obj if one could not be found
+        """
+        baseSolid = self.findSolid(searchParents=True)
+        r = obj
+        if baseSolid is not None:
+            r = baseSolid.cut(obj)
+
+        return self.newObject([r])
 
     def combine(self, clean=True):
         """
@@ -2770,6 +2784,45 @@ class Workplane(CQ):
             raise AttributeError(
                 "%s object doesn't support `clean()` method!" % obj.ShapeType())
         return self.newObject(cleanObjects)
+      
+    def text(self, txt, fontsize, distance, cut=True, combine=False, clean=True,
+             font="Arial", kind='regular'):
+        """
+        Create a 3D text
+
+        :param str txt: text to be rendered
+        :param distance: the distance to extrude, normal to the workplane plane
+        :type distance: float, negative means opposite the normal direction
+        :param float fontsize: size of the font
+        :param boolean cut: True to cut the resulting solid from the parent solids if found.
+        :param boolean combine: True to combine the resulting solid with parent solids if found.
+        :param boolean clean: call :py:meth:`clean` afterwards to have a clean shape
+        :param str font: fontname (default: Arial)
+        :param str kind: font type (default: Normal)
+        :return: a CQ object with the resulting solid selected.
+
+        extrude always *adds* material to a part.
+
+        The returned object is always a CQ object, and depends on wither combine is True, and
+        whether a context solid is already defined:
+
+        *  if combine is False, the new value is pushed onto the stack.
+        *  if combine is true, the value is combined with the context solid if it exists,
+           and the resulting solid becomes the new context solid.
+
+        """
+        r = Compound.makeText(txt,fontsize,distance,font=font,kind=kind,
+                              position=self.plane)
+        
+        if cut:
+            newS = self._cutFromBase(r)
+        elif combine:
+            newS = self._combineWithBase(r)
+        else:
+            newS = self.newObject([r])
+        if clean:
+            newS = newS.clean()
+        return newS
         
     def _repr_html_(self):
         """

cadquery/occ_impl/shapes.py

@@ -1,4 +1,4 @@
-from cadquery import Vector, BoundBox
+from cadquery import Vector, BoundBox, Plane
 
 import OCC.Core.TopAbs as ta  # Tolopolgy type enum
 import OCC.Core.GeomAbs as ga  # Geometry type enum
@@ -106,6 +106,11 @@ from OCC.LocOpe import LocOpe_DPrism
 
 from OCC.BRepCheck import BRepCheck_Analyzer
 
+from OCC.Core.Addons import (text_to_brep,
+                             Font_FA_Regular,
+                             Font_FA_Italic,
+                             Font_FA_Bold)
+
 from math import pi, sqrt
 
 TOLERANCE = 1e-6
@@ -1451,6 +1456,24 @@ class Compound(Shape, Mixin3D):
             comp_builder.Add(comp, s.wrapped)
 
         return cls(comp)
+      
+    @classmethod
+    def makeText(cls, text, size, height, font="Arial", kind='regular',
+                 position=Plane.XY()):
+        """
+        Create a 3D text
+        """
+        
+        font_kind = {'regular' : Font_FA_Regular,
+                     'bold'    : Font_FA_Bold,
+                     'italic'  : Font_FA_Italic}[kind]
+        
+        text_flat = Shape(text_to_brep(text, font, font_kind, size, False))
+        vecNormal = text_flat.Faces()[0].normalAt()*height
+        
+        text_3d = BRepPrimAPI_MakePrism(text_flat.wrapped, vecNormal.wrapped)
+        
+        return cls(text_3d.Shape()).transformShape(position.rG)
 
 # TODO this is likely not needed if sing PythonOCC.Core.correclty but we will see
 

tests/TestCadQuery.py

@@ -1800,3 +1800,27 @@ class TestCadQuery(BaseTest):
 
         # The obj1 shape shall have the same volume as the obj2 shape.
         self.assertAlmostEqual(obj1.val().Volume(), obj2.val().Volume())
+        
+    def testText(self):
+      
+        box = Workplane("XY" ).box(4, 4, 0.5)
+        
+        obj1 = box.faces('>Z').workplane().text('CQ 2.0',0.5,-.05,cut=True)
+        
+        #combined object should have smaller volume
+        self.assertGreater(box.val().Volume(),obj1.val().Volume())
+        
+        obj2 = box.faces('>Z').workplane()\
+            .text('CQ 2.0',0.5,.05,cut=False,combine=True)
+        
+        #combined object should have bigger volume
+        self.assertLess(box.val().Volume(),obj2.val().Volume())
+        
+        #verify that the number of top faces is correct (NB: this is font specific)
+        self.assertEqual(len(obj2.faces('>Z').vals()),5)
+        
+        obj3 = box.faces('>Z').workplane()\
+            .text('CQ 2.0',0.5,.05,cut=False,combine=False)
+            
+        #verify that the number of solids is correct
+        self.assertEqual(len(obj3.solids().vals()),5)