Files
ladybird/Libraries/LibWeb/Painting/SVGMaskable.cpp
Jelle Raaijmakers 90a211bf47 LibWeb: Use device-pixel coordinates in display list and AVC
Stop converting between CSS and device pixels as part of rendering - the
display list should be as simple as possible, so convert to DevicePixels
once when constructing the display list.
2026-02-26 07:43:00 +01:00

120 lines
4.7 KiB
C++

/*
* Copyright (c) 2024-2026, Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/Layout/SVGClipBox.h>
#include <LibWeb/Layout/SVGMaskBox.h>
#include <LibWeb/Painting/SVGClipPaintable.h>
#include <LibWeb/Painting/SVGGraphicsPaintable.h>
#include <LibWeb/Painting/StackingContext.h>
#include <LibWeb/SVG/SVGSVGElement.h>
namespace Web::Painting {
template<typename T>
static T const* first_child_layout_node_of_type(SVG::SVGGraphicsElement const& graphics_element)
{
if (!graphics_element.layout_node())
return nullptr;
return graphics_element.layout_node()->first_child_of_type<T>();
}
static auto get_mask_box(SVG::SVGGraphicsElement const& graphics_element)
{
return first_child_layout_node_of_type<Layout::SVGMaskBox>(graphics_element);
}
static auto get_clip_box(SVG::SVGGraphicsElement const& graphics_element)
{
return first_child_layout_node_of_type<Layout::SVGClipBox>(graphics_element);
}
Optional<CSSPixelRect> SVGMaskable::get_svg_mask_area() const
{
auto const& graphics_element = as<SVG::SVGGraphicsElement const>(*dom_node_of_svg());
if (auto* mask_box = get_mask_box(graphics_element))
return mask_box->dom_node().resolve_masking_area(mask_box->paintable_box()->absolute_border_box_rect());
return {};
}
Optional<CSSPixelRect> SVGMaskable::get_svg_clip_area() const
{
auto const& graphics_element = as<SVG::SVGGraphicsElement const>(*dom_node_of_svg());
if (auto* clip_box = get_clip_box(graphics_element))
return clip_box->paintable_box()->absolute_border_box_rect();
return {};
}
static Gfx::MaskKind mask_type_to_gfx_mask_kind(CSS::MaskType mask_type)
{
switch (mask_type) {
case CSS::MaskType::Alpha:
return Gfx::MaskKind::Alpha;
case CSS::MaskType::Luminance:
return Gfx::MaskKind::Luminance;
default:
VERIFY_NOT_REACHED();
}
}
Optional<Gfx::MaskKind> SVGMaskable::get_svg_mask_type() const
{
auto const& graphics_element = as<SVG::SVGGraphicsElement const>(*dom_node_of_svg());
if (auto* mask_box = get_mask_box(graphics_element))
return mask_type_to_gfx_mask_kind(mask_box->computed_values().mask_type());
return {};
}
static RefPtr<DisplayList> paint_mask_or_clip_to_display_list(
DisplayListRecordingContext& context,
Gfx::AffineTransform const& target_svg_transform,
PaintableBox const& paintable,
CSSPixelRect const& area,
bool is_clip_path)
{
auto mask_rect = context.enclosing_device_rect(area);
auto display_list = DisplayList::create();
DisplayListRecorder display_list_recorder(*display_list);
display_list_recorder.translate(-mask_rect.location().to_type<int>());
auto paint_context = context.clone(display_list_recorder);
auto const& mask_element = as<SVG::SVGGraphicsElement const>(*paintable.dom_node());
// Layout computes transforms only within the mask/clip subtree, so prepend the target's accumulated transform here.
auto svg_transform = Gfx::AffineTransform { target_svg_transform }.multiply(mask_element.element_transform());
paint_context.set_svg_transform(svg_transform);
paint_context.set_draw_svg_geometry_for_clip_path(is_clip_path);
StackingContext::paint_svg(paint_context, paintable, PaintPhase::Foreground);
return display_list;
}
Gfx::AffineTransform SVGMaskable::target_svg_transform() const
{
// Only SVGGraphicsPaintable carries an SVG transform; other targets (e.g. foreign objects) use identity.
if (auto const* svg_graphics_paintable = as_if<SVGGraphicsPaintable>(*this))
return svg_graphics_paintable->computed_transforms().svg_transform();
return {};
}
RefPtr<DisplayList> SVGMaskable::calculate_svg_mask_display_list(DisplayListRecordingContext& context, CSSPixelRect const& mask_area) const
{
auto const& graphics_element = as<SVG::SVGGraphicsElement const>(*dom_node_of_svg());
auto* mask_box = get_mask_box(graphics_element);
if (!mask_box)
return nullptr;
auto& mask_paintable = static_cast<PaintableBox const&>(*mask_box->first_paintable());
return paint_mask_or_clip_to_display_list(context, target_svg_transform(), mask_paintable, mask_area, false);
}
RefPtr<DisplayList> SVGMaskable::calculate_svg_clip_display_list(DisplayListRecordingContext& context, CSSPixelRect const& clip_area) const
{
auto const& graphics_element = as<SVG::SVGGraphicsElement const>(*dom_node_of_svg());
auto* clip_box = get_clip_box(graphics_element);
if (!clip_box)
return nullptr;
auto& clip_paintable = static_cast<PaintableBox const&>(*clip_box->first_paintable());
return paint_mask_or_clip_to_display_list(context, target_svg_transform(), clip_paintable, clip_area, true);
}
}