[instancer-solver] Fix a bug

Fixes #3139
fonttools · May 29, 2023 · 661d6fc · 661d6fc
1 parent b8dcb85
commit 661d6fc
Show file tree

Hide file tree

Showing 2 changed files with 13 additions and 1 deletion.
diff --git a/Lib/fontTools/varLib/instancer/solver.py b/Lib/fontTools/varLib/instancer/solver.py
@@ -102,7 +102,7 @@ def _solve(tent, axisLimit, negative=False):
         # Crossing point on the axis.
         crossing = peak + ((1 - gain) * (upper - peak) / (1 - outGain))
 
-        loc = (peak, peak, crossing)
+        loc = (axisDef, peak, crossing)
         scalar = 1
 
         # The part before the crossing point.

diff --git a/Tests/varLib/instancer/solver_test.py b/Tests/varLib/instancer/solver_test.py
@@ -218,6 +218,18 @@ class RebaseTentTest(object):
                     (1, (0, 0.4, 1.99994)),
                 ],
             ),
+            # https://github.com/fonttools/fonttools/issues/3139
+            pytest.param(
+                (0, 0.5, 1),
+                (-1, .25, 1),
+                [
+                    (.5, None),
+                    (0.5, (0.0, 1/3, 2/3)),
+                    (-0.5, (2/3, 1, 1)),
+                    (-0.5, (-1, -.2, 0)),
+                    (-0.5, (-1, -1, -.2)),
+                ],
+            ),
             # Dirac delta at new default. Fancy!
             pytest.param(
                 (0.5, 0.5, 0.5),