Fix remaining svg rendering/gerber compositing bugs

2 files changed, 10 insertions, 6 deletions

diff --git a/gerbonara/gerber/tests/image_support.py b/gerbonara/gerber/tests/image_support.py
index ee84203..ba28561 100644
--- a/gerbonara/gerber/tests/image_support.py
+++ b/gerbonara/gerber/tests/image_support.py
@@ -63,13 +63,14 @@ def run_cargo_cmd(cmd, args, **kwargs):
 def svg_to_png(in_svg, out_png, dpi=100, bg='black'):
     run_cargo_cmd('resvg', ['--background', bg, '--dpi', str(dpi), in_svg, out_png], check=True, stdout=subprocess.DEVNULL)
 
-def gerbv_export(in_gbr, out_svg, format='svg', origin=(0, 0), size=(6, 6), fg='#ffffff'):
+def gerbv_export(in_gbr, out_svg, format='svg', origin=(0, 0), size=(6, 6), fg='#ffffff', bg='#000000'):
     x, y = origin
     w, h = size
     cmd = ['gerbv', '-x', format,
         '--border=0',
         f'--origin={x:.6f}x{y:.6f}', f'--window_inch={w:.6f}x{h:.6f}',
         f'--foreground={fg}',
+        f'--background={bg}',
         '-o', str(out_svg), str(in_gbr)]
     subprocess.run(cmd, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
 
diff --git a/gerbonara/gerber/tests/test_rs274x.py b/gerbonara/gerber/tests/test_rs274x.py
index 5be0af5..7382997 100644
--- a/gerbonara/gerber/tests/test_rs274x.py
+++ b/gerbonara/gerber/tests/test_rs274x.py
@@ -46,7 +46,7 @@ def print_on_error(request):
 
     if request.node.rep_call.failed:
         for msg in messages:
-            print(msg)
+            print(msg, end='')
 
 @pytest.fixture
 def tmpfile(request):
@@ -322,8 +322,14 @@ def test_svg_export(reference, tmpfile):
     with open(out_svg, 'w') as f:
         f.write(str(grb.to_svg(force_bounds=bounds, arg_unit='inch', color='white')))
 
+    # NOTE: Instead of having gerbv directly export a PNG, we ask gerbv to output SVG which we then rasterize using
+    # resvg. We have to do this since gerbv's built-in cairo-based PNG export has severe aliasing issues. In contrast,
+    # using resvg for both allows an apples-to-apples comparison of both results.
+    ref_svg = tmpfile('Reference export', '.svg')
     ref_png = tmpfile('Reference render', '.png')
-    gerbv_export(reference, ref_png, origin=bounds[0], size=bounds[1], format='png', fg='#000000')
+    gerbv_export(reference, ref_svg, origin=bounds[0], size=bounds[1])
+    svg_to_png(ref_svg, ref_png, dpi=72) # make dpi match Cairo's default
+
     out_png = tmpfile('Output render', '.png')
     svg_to_png(out_svg, out_png, dpi=72) # make dpi match Cairo's default
 
@@ -363,11 +369,8 @@ def test_bounding_box(reference, tmpfile):
     assert (img > 0).any() # there must be some content, none of the test gerbers are completely empty.
     cols = img.sum(axis=1)
     rows = img.sum(axis=0)
-    print('shape:', img.shape)
     col_prefix, col_suffix = np.argmax(cols > 0), np.argmax(cols[::-1] > 0)
     row_prefix, row_suffix = np.argmax(rows > 0), np.argmax(rows[::-1] > 0)
-    print('cols', 'prefix:', row_prefix, 'suffix:', row_suffix)
-    print('rows', 'prefix:', row_prefix, 'suffix:', row_suffix)
 
     # Check that all margins are completely black and that the content touches the margins. Allow for some tolerance to
     # allow for antialiasing artifacts.