Fix sdl2.ext.draw on 1bpp surfaces

AUTHORS.txt

@@ -11,6 +11,7 @@ with contributions from
 
 Thanks to everyone else for their assistance, support, fixes and improvements:
 
+* A-Wpro
 * Andreas Schiefer
 * Bao "Mantle" Rong
 * Ben Greiner 

doc/news.rst

@@ -21,6 +21,7 @@ Fixed Bugs:
 
 * Fixed broken behaviour (and potential segfaults) with usage of
   :func:`sdl2.SDL_GUIDToString` on Python 3.6 and older (PR #246).
+* Fixed :func:`sdl2.ext.draw` when drawing on 1bpp surfaces (PR #242).
 
 
 0.9.13

sdl2/ext/draw.py

@@ -148,7 +148,9 @@ def line(target, color, dline, width=1):
 
     if bpp == 3:
         raise UnsupportedError("24bpp surfaces are not currently supported.")
-    if bpp == 2:
+    if bpp == 1:
+        pxbuf = ctypes.cast(rtarget.pixels, ctypes.POINTER(ctypes.c_uint8))
+    elif bpp == 2:
         pxbuf = ctypes.cast(rtarget.pixels, ctypes.POINTER(ctypes.c_uint16))
     elif bpp == 4:
         pxbuf = ctypes.cast(rtarget.pixels, ctypes.POINTER(ctypes.c_uint32))

sdl2/test/sdl2ext_draw_test.py

@@ -109,6 +109,13 @@ def test_line(testsurf):
     assert all(x == 255 for x in view[-1][-1][:3])
     assert all(x == 0 for x in view[1][5][:3])
 
+    # Test surfaces with nonstandard bpp values
+    fmts = ["RGB332", "RGBA4444"]
+    for f in fmts:
+        sf2 = _create_surface((10, 10), fmt=f)
+        sdl2ext.line(sf2.contents, WHITE, (1, 1, 9, 9))
+        SDL_FreeSurface(sf2)
+
     # Test exception on bad input
     with pytest.raises(ValueError):
         sdl2ext.line(sf.contents, WHITE, (1, 2, 3))