Fix test structure and add rendering tests

test/__init__.py

@@ -1,5 +1,7 @@
+from .test_element_rendering import *
 from .test_markup import *
 
 __all__ = []
 
 __all__+= test_element_rendering.__all__
+__all__+= test_markup.__all__

test/test_element_rendering.py

@@ -0,0 +1,26 @@
+import unittest
+
+import cheuph
+
+__all__ = ["TestCursorTreeRenderer"]
+
+class TestCursorTreeRenderer(unittest.TestCase):
+
+    def test_static_offset(self):
+        gao = cheuph.CursorTreeRenderer.get_absolute_offset
+        gro = cheuph.CursorTreeRenderer.get_relative_offset
+
+        self.assertEqual(0, gao(0.0, 6))
+        self.assertEqual(1, gao(0.2, 6))
+        self.assertEqual(2, gao(0.4, 6))
+        self.assertEqual(3, gao(0.6, 6))
+        self.assertEqual(4, gao(0.8, 6))
+        self.assertEqual(5, gao(1.0, 6))
+
+        for i in range(1, 1000):
+            self.assertEqual(0, gao(0.0, i))
+            self.assertEqual(i, gao(1.0, i + 1))
+
+        height = 1000
+        for i in range(height):
+            self.assertEqual(i, gao(gro(i, height), height))