LibWeb: Position grid items with fixed row positions

This commit is contained in:
martinfalisse 2022-09-07 15:35:01 +02:00 committed by Andreas Kling
parent f143fefca2
commit 707b76ed41
Notes: sideshowbarker 2024-07-17 16:23:55 +09:00

View File

@ -170,6 +170,69 @@ void GridFormattingContext::run(Box const& box, LayoutMode)
}
// 2. Process the items locked to a given row.
// FIXME: Do "dense" packing
for (size_t i = 0; i < boxes_to_place.size(); i++) {
auto const& child_box = boxes_to_place[i];
if (child_box.computed_values().grid_row_start().is_auto()
|| child_box.computed_values().grid_row_end().is_auto())
continue;
int row_start = child_box.computed_values().grid_row_start().position();
int row_end = child_box.computed_values().grid_row_end().position();
int row_span = 1;
// https://drafts.csswg.org/css-grid/#grid-placement-int
// [ <integer [−∞,1]> | <integer [1,∞]> ] && <custom-ident>?
// Contributes the Nth grid line to the grid items placement. If a negative integer is given, it
// instead counts in reverse, starting from the end edge of the explicit grid.
if (row_end < 0)
row_end = static_cast<int>(occupation_grid.size()) + row_end + 2;
// FIXME: If a name is given as a <custom-ident>, only lines with that name are counted. If not enough
// lines with that name exist, all implicit grid lines are assumed to have that name for the purpose
// of finding this position.
// FIXME: An <integer> value of zero makes the declaration invalid.
// https://drafts.csswg.org/css-grid/#grid-placement-errors
// 8.3.1. Grid Placement Conflict Handling
// If the placement for a grid item contains two lines, and the start line is further end-ward than
// the end line, swap the two lines. If the start line is equal to the end line, remove the end
// line.
if (row_start > row_end) {
auto temp = row_end;
row_end = row_start;
row_start = temp;
}
if (row_start != row_end)
row_span = row_end - row_start;
// FIXME: If the placement contains two spans, remove the one contributed by the end grid-placement
// property.
// FIXME: If the placement contains only a span for a named line, replace it with a span of 1.
row_start -= 1;
maybe_add_row_to_occupation_grid(row_start + row_span, occupation_grid);
int column_start = 0;
int column_span = 1;
bool found_available_column = false;
for (int column_index = column_start; column_index < (int)occupation_grid[0].size(); column_index++) {
if (!occupation_grid[0][column_index]) {
found_available_column = true;
column_start = column_index;
break;
}
}
if (!found_available_column) {
column_start = occupation_grid[0].size();
maybe_add_column_to_occupation_grid(column_start + column_span, occupation_grid);
}
set_occupied_cells(row_start, row_start + row_span, column_start, column_start + column_span, occupation_grid);
positioned_boxes.append({ child_box, row_start, row_span, column_start, column_span });
boxes_to_place.remove(i);
i--;
}
// 3. Determine the columns in the implicit grid.