Fix crash in wxImage::Paste() when using images without alpha

Check for the presence of alpha channel before using it in the fallback
code.

Also add a unit test exercising this branch of the code and which
crashed before.
This commit is contained in:
Hartwig 2020-10-05 18:17:16 +02:00 committed by Vadim Zeitlin
parent d58f9bea72
commit 728f2f958f
2 changed files with 8 additions and 3 deletions

View File

@ -1786,12 +1786,13 @@ wxImage::Paste(const wxImage & image, int x, int y,
{
// Copy the non masked pixel
memcpy(target_data + i, source_data + i, 3);
// Make the copied pixel fully opaque
if (alpha_target_data != NULL) // Make the copied pixel fully opaque
alpha_target_data[i / 3] = wxALPHA_OPAQUE;
}
}
source_data += source_step;
target_data += target_step;
if (alpha_target_data != NULL)
alpha_target_data += target_alpha_step;
}
}

View File

@ -1540,6 +1540,10 @@ TEST_CASE("wxImage::Paste", "[image][paste]")
wxImage expected(toggle_equal_size_xpm);
actual.Paste(paste, 0, 0);
CHECK_THAT(actual, RGBSameAs(expected));
// Without alpha using "compose" doesn't change anything.
actual.Paste(paste, 0, 0, wxIMAGE_ALPHA_BLEND_COMPOSE);
CHECK_THAT(actual, RGBSameAs(expected));
}
SECTION("Paste larger image")