diff --git a/Libraries/LibWeb/Page/EventHandler.cpp b/Libraries/LibWeb/Page/EventHandler.cpp index 4d3c5859de1..870fc064410 100644 --- a/Libraries/LibWeb/Page/EventHandler.cpp +++ b/Libraries/LibWeb/Page/EventHandler.cpp @@ -136,13 +136,44 @@ static Gfx::StandardCursor cursor_css_to_gfx(Optional cursor) } } +// https://drafts.csswg.org/cssom-view/#dom-mouseevent-offsetx static CSSPixelPoint compute_mouse_event_offset(CSSPixelPoint position, Layout::Node const& layout_node) { - auto top_left_of_layout_node = layout_node.first_paintable()->box_type_agnostic_position(); - return { - position.x() - top_left_of_layout_node.x(), - position.y() - top_left_of_layout_node.y() + // If the event’s dispatch flag is set, + // FIXME: Is this guaranteed to be dispatched? + + // return the x-coordinate of the position where the event occurred, + Gfx::Point precision_offset = { + position.x().to_double(), + position.y().to_double() }; + + // ignoring the transforms that apply to the element and its ancestors, + if (layout_node.has_css_transform()) { + auto const& paintable_box = layout_node.dom_node()->paintable_box(); + auto const affine_transform = Gfx::extract_2d_affine_transform(paintable_box->transform().inverse()); + + auto const& origin = paintable_box->transform_origin(); + Gfx::Point const precision_origin = { + origin.x().to_double(), + origin.y().to_double() + }; + + precision_offset.translate_by(-precision_origin); + precision_offset.transform_by(affine_transform); + precision_offset.translate_by(precision_origin); + } + + // relative to the origin of the padding edge of the target node + auto const top_left_of_layout_node = layout_node.first_paintable()->box_type_agnostic_position(); + CSSPixelPoint offset = { + CSSPixels(precision_offset.x()), + CSSPixels(precision_offset.y()) + }; + offset -= top_left_of_layout_node; + + // and terminate these steps. + return offset; } EventHandler::EventHandler(Badge, HTML::Navigable& navigable) diff --git a/Tests/LibWeb/Text/expected/CSSOMView/mouse-event-offset-values.txt b/Tests/LibWeb/Text/expected/CSSOMView/mouse-event-offset-values.txt new file mode 100644 index 00000000000..cab2f2a7f70 --- /dev/null +++ b/Tests/LibWeb/Text/expected/CSSOMView/mouse-event-offset-values.txt @@ -0,0 +1,2 @@ +offsetX: 45.75 +offsetY: 57.078125 diff --git a/Tests/LibWeb/Text/input/CSSOMView/mouse-event-offset-values.html b/Tests/LibWeb/Text/input/CSSOMView/mouse-event-offset-values.html new file mode 100644 index 00000000000..39067557c7f --- /dev/null +++ b/Tests/LibWeb/Text/input/CSSOMView/mouse-event-offset-values.html @@ -0,0 +1,21 @@ + + +
+ + + +