LibGfx:: Implement scale support for blit_with_opacity()

Now we no longer crash on mousewheel over Terminal while holding the
super key. The terminal window doesn't yet correctly become transparent
in hidpi mode (needs more investigation), but it works in LibGfxScaleDemo,
so maybe that's a problem elsewhere.

Also add a FIXME for a pre-existing bug.

1 files changed, 6 insertions, 0 deletions

diff --git a/Userland/Demos/LibGfxScaleDemo/main.cpp b/Userland/Demos/LibGfxScaleDemo/main.cpp
index 7352420d31..aa4552fc81 100644
--- a/Userland/Demos/LibGfxScaleDemo/main.cpp
+++ b/Userland/Demos/LibGfxScaleDemo/main.cpp
@@ -98,6 +98,7 @@ void Canvas::draw(Gfx::Painter& painter)
     painter.draw_rect({ 20, 34, WIDTH - 40, HEIGHT - 45 }, palette().color(Gfx::ColorRole::Selection), true);
     painter.draw_rect({ 24, 38, WIDTH - 48, HEIGHT - 53 }, palette().color(Gfx::ColorRole::Selection));
 
+    // buggie.png has an alpha channel.
     auto buggie = Gfx::Bitmap::load_from_file("/res/graphics/buggie.png");
     painter.blit({ 25, 39 }, *buggie, { 2, 30, 62, 20 });
     painter.draw_scaled_bitmap({ 88, 39, 62 * 2, 20 * 2 }, *buggie, Gfx::IntRect { 2, 30, 62, 20 });
@@ -106,6 +107,11 @@ void Canvas::draw(Gfx::Painter& painter)
     painter.draw_tiled_bitmap({ 25, 60, WIDTH - 50, 40 }, *buggie);
 
     painter.blit({ 25, 101 }, *buggie, { 2, 30, 3 * buggie->width(), 20 });
+
+    // banner does not have an alpha channel.
+    auto banner = Gfx::Bitmap::load_from_file("/res/graphics/brand-banner.png");
+    painter.fill_rect({ 25, 122, 28, 20 }, Color::Green);
+    painter.blit({ 25, 122 }, *banner, { 314, 12, 28, 20 }, 0.8);
 }
 
 int main(int argc, char** argv)