Improve text alignment (#1455)

* Add test to check text alignment options

* Improve text alignment

* Simplify text alignment tests in Cadquery

* Refactor text alignment in shapes module

* Remove unused import in test_cadquery module

* Refactor alignment tests in test_cadquery

* Adjust volume value in exporter test

Author: egrim

cadquery/occ_impl/shapes.py

@@ -200,6 +200,14 @@
 )
 
 from OCP.StdPrs import StdPrs_BRepFont, StdPrs_BRepTextBuilder as Font_BRepTextBuilder
+from OCP.Graphic3d import (
+    Graphic3d_HTA_LEFT,
+    Graphic3d_HTA_CENTER,
+    Graphic3d_HTA_RIGHT,
+    Graphic3d_VTA_BOTTOM,
+    Graphic3d_VTA_CENTER,
+    Graphic3d_VTA_TOP,
+)
 
 from OCP.NCollection import NCollection_Utf8String
 
@@ -3665,23 +3673,28 @@ def makeText(
             font_kind,
             float(size),
         )
-        text_flat = Shape(builder.Perform(font_i, NCollection_Utf8String(text)))
-
-        bb = text_flat.BoundingBox()
-
-        t = Vector()
-
-        if halign == "center":
-            t.x = -bb.xlen / 2
-        elif halign == "right":
-            t.x = -bb.xlen
-
-        if valign == "center":
-            t.y = -bb.ylen / 2
-        elif valign == "top":
-            t.y = -bb.ylen
-
-        text_flat = text_flat.translate(t)
+        if halign == "left":
+            theHAlign = Graphic3d_HTA_LEFT
+        elif halign == "center":
+            theHAlign = Graphic3d_HTA_CENTER
+        else:  # halign == "right"
+            theHAlign = Graphic3d_HTA_RIGHT
+
+        if valign == "bottom":
+            theVAlign = Graphic3d_VTA_BOTTOM
+        elif valign == "center":
+            theVAlign = Graphic3d_VTA_CENTER
+        else:  # valign == "top":
+            theVAlign = Graphic3d_VTA_TOP
+
+        text_flat = Shape(
+            builder.Perform(
+                font_i,
+                NCollection_Utf8String(text),
+                theHAlign=theHAlign,
+                theVAlign=theVAlign,
+            )
+        )
 
         if height != 0:
             vecNormal = text_flat.Faces()[0].normalAt() * height

tests/test_cadquery.py

@@ -3875,6 +3875,22 @@ def testText(self):
             )
         )
 
+    def testTextAlignment(self):
+        left_bottom = Workplane().text("I", 10, 0, halign="left", valign="bottom")
+        lb_bb = left_bottom.val().BoundingBox()
+        self.assertGreaterEqual(lb_bb.xmin, 0)
+        self.assertGreaterEqual(lb_bb.ymin, 0)
+
+        centers = Workplane().text("I", 10, 0, halign="center", valign="center")
+        c_bb = centers.val().BoundingBox()
+        self.assertAlmostEqual(c_bb.center.x, 0, places=0)
+        self.assertAlmostEqual(c_bb.center.y, 0, places=0)
+
+        right_top = Workplane().text("I", 10, 0, halign="right", valign="top")
+        rt_bb = right_top.val().BoundingBox()
+        self.assertLessEqual(rt_bb.xmax, 0)
+        self.assertLessEqual(rt_bb.ymax, 0)
+
     def testParametricCurve(self):
 
         from math import sin, cos, pi

tests/test_exporters.py

@@ -910,7 +910,7 @@ def test_dxf_text(tmpdir, testdatadir):
     s2 = Sketch().importDXF(fname)
     w2 = Workplane("XZ", origin=(0, -0.5, 0)).placeSketch(s2).extrude(-1)
 
-    assert w1.val().Volume() == approx(59.983287, 1e-2)
+    assert w1.val().Volume() == approx(61.669465, 1e-2)
     assert w2.val().Volume() == approx(w1.val().Volume(), 1e-2)
     assert w2.intersect(w1).val().Volume() == approx(w1.val().Volume(), 1e-2)