// Copyright 2020 The Chromium Authors // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include "third_party/blink/renderer/core/paint/mathml_painter.h" #include "third_party/blink/renderer/core/layout/mathml/math_layout_utils.h" #include "third_party/blink/renderer/core/mathml/mathml_radical_element.h" #include "third_party/blink/renderer/core/paint/box_fragment_painter.h" #include "third_party/blink/renderer/core/paint/paint_auto_dark_mode.h" #include "third_party/blink/renderer/core/paint/paint_info.h" #include "third_party/blink/renderer/platform/fonts/text_fragment_paint_info.h" #include "third_party/blink/renderer/platform/geometry/layout_unit.h" #include "third_party/blink/renderer/platform/graphics/graphics_context_state_saver.h" #include "third_party/blink/renderer/platform/graphics/paint/drawing_recorder.h" namespace blink { void MathMLPainter::PaintBar(const PaintInfo& info, const PhysicalRect& bar_rect) { gfx::Rect snapped_bar_rect = ToPixelSnappedRect(bar_rect); if (snapped_bar_rect.IsEmpty()) { return; } // The (vertical) origin of `snapped_bar_rect` is now at the mid-point of the // bar. Shift up by half the height to produce the corresponding rectangle. snapped_bar_rect -= gfx::Vector2d(0, snapped_bar_rect.height() / 2); const ComputedStyle& style = box_fragment_.Style(); info.context.FillRect( snapped_bar_rect, style.VisitedDependentColor(GetCSSPropertyColor()), PaintAutoDarkMode(style, DarkModeFilter::ElementRole::kForeground)); } void MathMLPainter::PaintStretchyOrLargeOperator(const PaintInfo& info, PhysicalOffset paint_offset) { const ComputedStyle& style = box_fragment_.Style(); const MathMLPaintInfo& parameters = box_fragment_.GetMathMLPaintInfo(); UChar operator_character = parameters.operator_character; TextFragmentPaintInfo text_fragment_paint_info = { StringView(base::span_from_ref(operator_character)), 0, 1, parameters.operator_shape_result_view.Get()}; GraphicsContextStateSaver state_saver(info.context); info.context.SetFillColor(style.VisitedDependentColor(GetCSSPropertyColor())); AutoDarkMode auto_dark_mode( PaintAutoDarkMode(style, DarkModeFilter::ElementRole::kForeground)); info.context.DrawText(*style.GetFont(), text_fragment_paint_info, gfx::PointF(paint_offset), kInvalidDOMNodeId, auto_dark_mode); } void MathMLPainter::PaintFractionBar(const PaintInfo& info, PhysicalOffset paint_offset) { DCHECK(box_fragment_.Style().IsHorizontalWritingMode()); const ComputedStyle& style = box_fragment_.Style(); LayoutUnit line_thickness = FractionLineThickness(style); if (!line_thickness) return; LayoutUnit axis_height = MathAxisHeight(style); if (auto baseline = box_fragment_.FirstBaseline()) { auto borders = box_fragment_.Borders(); auto padding = box_fragment_.Padding(); PhysicalRect bar_rect = { borders.left + padding.left, *baseline - axis_height, box_fragment_.Size().width - borders.HorizontalSum() - padding.HorizontalSum(), line_thickness}; bar_rect.Move(paint_offset); PaintBar(info, bar_rect); } } void MathMLPainter::PaintOperator(const PaintInfo& info, PhysicalOffset paint_offset) { const ComputedStyle& style = box_fragment_.Style(); const MathMLPaintInfo& parameters = box_fragment_.GetMathMLPaintInfo(); LogicalOffset offset(LayoutUnit(), parameters.operator_ascent); PhysicalOffset physical_offset = offset.ConvertToPhysical( style.GetWritingDirection(), PhysicalSize(box_fragment_.Size().width, box_fragment_.Size().height), PhysicalSize(parameters.operator_inline_size, parameters.operator_ascent + parameters.operator_descent)); auto borders = box_fragment_.Borders(); auto padding = box_fragment_.Padding(); physical_offset.left += borders.left + padding.left; physical_offset.top += borders.top + padding.top; // TODO(http://crbug.com/1124301): MathOperatorLayoutAlgorithm::Layout // passes the operator's inline size but this does not match the width of the // box fragment, which relies on the min-max sizes instead. Shift the paint // offset to work around that issue, splitting the size error symmetrically. DCHECK(box_fragment_.Style().IsHorizontalWritingMode()); bool is_ltr = style.GetWritingDirection().IsLtr() || !RuntimeEnabledFeatures::MathMLOperatorRTLMirroringEnabled(); physical_offset.left += (box_fragment_.Size().width - borders.HorizontalSum() - padding.HorizontalSum() - parameters.operator_inline_size) / 2 * (is_ltr ? 1 : -1); PaintStretchyOrLargeOperator(info, paint_offset + physical_offset); } void MathMLPainter::PaintRadicalSymbol(const PaintInfo& info, PhysicalOffset paint_offset) { LayoutUnit base_child_width; LayoutUnit base_child_ascent; if (!box_fragment_.Children().empty()) { const auto& base_child = To(*box_fragment_.Children()[0]); base_child_width = base_child.Size().width; base_child_ascent = base_child.FirstBaseline().value_or(base_child.Size().height); } const MathMLPaintInfo& parameters = box_fragment_.GetMathMLPaintInfo(); DCHECK(box_fragment_.Style().IsHorizontalWritingMode()); // Paint the vertical symbol. const ComputedStyle& style = box_fragment_.Style(); bool has_index = To(box_fragment_.GetNode())->HasIndex(); auto vertical = GetRadicalVerticalParameters(style, has_index); auto radical_base_ascent = base_child_ascent + parameters.radical_base_margins.inline_start; LayoutUnit block_offset = box_fragment_.FirstBaseline().value_or(box_fragment_.Size().height) - vertical.vertical_gap - radical_base_ascent; auto borders = box_fragment_.Borders(); auto padding = box_fragment_.Padding(); LayoutUnit inline_offset = borders.left + padding.left; inline_offset += *parameters.radical_operator_inline_offset; LogicalOffset radical_symbol_offset( inline_offset, block_offset + parameters.operator_ascent); auto radical_symbol_physical_offset = radical_symbol_offset.ConvertToPhysical( style.GetWritingDirection(), PhysicalSize(box_fragment_.Size().width, box_fragment_.Size().height), PhysicalSize(RuntimeEnabledFeatures::MathMLOperatorRTLMirroringEnabled() ? parameters.operator_inline_size : parameters.operator_ascent, parameters.operator_ascent + parameters.operator_descent)); PaintStretchyOrLargeOperator(info, paint_offset + radical_symbol_physical_offset); // Paint the horizontal overbar. LayoutUnit rule_thickness = vertical.rule_thickness; if (!rule_thickness) return; LayoutUnit base_width = base_child_width + parameters.radical_base_margins.InlineSum(); LogicalOffset bar_offset = LogicalOffset(inline_offset, block_offset) + LogicalSize(parameters.operator_inline_size, LayoutUnit()); auto bar_physical_offset = bar_offset.ConvertToPhysical( style.GetWritingDirection(), box_fragment_.Size(), PhysicalSize(base_width, rule_thickness)); PhysicalRect bar_rect = {bar_physical_offset.left, bar_physical_offset.top, base_width, rule_thickness}; bar_rect.Move(paint_offset); PaintBar(info, bar_rect); } void MathMLPainter::Paint(const PaintInfo& info, PhysicalOffset paint_offset) { const DisplayItemClient& display_item_client = *box_fragment_.GetLayoutObject(); if (DrawingRecorder::UseCachedDrawingIfPossible( info.context, display_item_client, info.phase)) return; DrawingRecorder recorder( info.context, display_item_client, info.phase, BoxFragmentPainter(box_fragment_).VisualRect(paint_offset)); // Fraction if (box_fragment_.IsMathMLFraction()) { PaintFractionBar(info, paint_offset); return; } // Radical symbol if (box_fragment_.GetMathMLPaintInfo().IsRadicalOperator()) { PaintRadicalSymbol(info, paint_offset); return; } // Operator PaintOperator(info, paint_offset); } } // namespace blink