diff options
Diffstat (limited to 'source/blender/editors/interface/views/grid_view.cc')
| -rw-r--r-- | source/blender/editors/interface/views/grid_view.cc | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/source/blender/editors/interface/views/grid_view.cc b/source/blender/editors/interface/views/grid_view.cc new file mode 100644 index 00000000000..52ff1460cbd --- /dev/null +++ b/source/blender/editors/interface/views/grid_view.cc @@ -0,0 +1,463 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +/** \file + * \ingroup edinterface + */ + +#include <limits> +#include <stdexcept> + +#include "BLI_index_range.hh" + +#include "WM_types.h" + +#include "UI_interface.h" +#include "interface_intern.h" + +#include "UI_grid_view.hh" + +namespace blender::ui { + +/* ---------------------------------------------------------------------- */ + +AbstractGridView::AbstractGridView() : style_(UI_preview_tile_size_x(), UI_preview_tile_size_y()) +{ +} + +AbstractGridViewItem &AbstractGridView::add_item(std::unique_ptr<AbstractGridViewItem> item) +{ + items_.append(std::move(item)); + + AbstractGridViewItem &added_item = *items_.last(); + item_map_.add(added_item.identifier_, &added_item); + register_item(added_item); + + return added_item; +} + +void AbstractGridView::foreach_item(ItemIterFn iter_fn) const +{ + for (const auto &item_ptr : items_) { + iter_fn(*item_ptr); + } +} + +AbstractGridViewItem *AbstractGridView::find_matching_item( + const AbstractGridViewItem &item_to_match, const AbstractGridView &view_to_search_in) const +{ + AbstractGridViewItem *const *match = view_to_search_in.item_map_.lookup_ptr( + item_to_match.identifier_); + BLI_assert(!match || item_to_match.matches(**match)); + + return match ? *match : nullptr; +} + +void AbstractGridView::change_state_delayed() +{ + BLI_assert_msg( + is_reconstructed(), + "These state changes are supposed to be delayed until reconstruction is completed"); + foreach_item([](AbstractGridViewItem &item) { item.change_state_delayed(); }); +} + +void AbstractGridView::update_children_from_old(const AbstractView &old_view) +{ + const AbstractGridView &old_grid_view = dynamic_cast<const AbstractGridView &>(old_view); + + foreach_item([this, &old_grid_view](AbstractGridViewItem &new_item) { + const AbstractGridViewItem *matching_old_item = find_matching_item(new_item, old_grid_view); + if (!matching_old_item) { + return; + } + + new_item.update_from_old(*matching_old_item); + }); +} + +const GridViewStyle &AbstractGridView::get_style() const +{ + return style_; +} + +int AbstractGridView::get_item_count() const +{ + return items_.size(); +} + +GridViewStyle::GridViewStyle(int width, int height) : tile_width(width), tile_height(height) +{ +} + +/* ---------------------------------------------------------------------- */ + +AbstractGridViewItem::AbstractGridViewItem(StringRef identifier) : identifier_(identifier) +{ +} + +bool AbstractGridViewItem::matches(const AbstractViewItem &other) const +{ + const AbstractGridViewItem &other_grid_item = dynamic_cast<const AbstractGridViewItem &>(other); + return identifier_ == other_grid_item.identifier_; +} + +void AbstractGridViewItem::grid_tile_click_fn(struct bContext * /*C*/, + void *but_arg1, + void * /*arg2*/) +{ + uiButViewItem *view_item_but = (uiButViewItem *)but_arg1; + AbstractGridViewItem &grid_item = reinterpret_cast<AbstractGridViewItem &>( + *view_item_but->view_item); + + grid_item.activate(); +} + +void AbstractGridViewItem::add_grid_tile_button(uiBlock &block) +{ + const GridViewStyle &style = get_view().get_style(); + view_item_but_ = (uiButViewItem *)uiDefBut(&block, + UI_BTYPE_VIEW_ITEM, + 0, + "", + 0, + 0, + style.tile_width, + style.tile_height, + nullptr, + 0, + 0, + 0, + 0, + ""); + + view_item_but_->view_item = reinterpret_cast<uiViewItemHandle *>(this); + UI_but_func_set(&view_item_but_->but, grid_tile_click_fn, view_item_but_, nullptr); +} + +void AbstractGridViewItem::on_activate() +{ + /* Do nothing by default. */ +} + +std::optional<bool> AbstractGridViewItem::should_be_active() const +{ + return std::nullopt; +} + +void AbstractGridViewItem::change_state_delayed() +{ + const std::optional<bool> should_be_active = this->should_be_active(); + if (should_be_active.has_value() && *should_be_active) { + activate(); + } +} + +void AbstractGridViewItem::activate() +{ + BLI_assert_msg(get_view().is_reconstructed(), + "Item activation can't be done until reconstruction is completed"); + + if (is_active()) { + return; + } + + /* Deactivate other items in the tree. */ + get_view().foreach_item([](auto &item) { item.deactivate(); }); + + on_activate(); + + is_active_ = true; +} + +void AbstractGridViewItem::deactivate() +{ + is_active_ = false; +} + +const AbstractGridView &AbstractGridViewItem::get_view() const +{ + if (UNLIKELY(!view_)) { + throw std::runtime_error( + "Invalid state, item must be added through AbstractGridView::add_item()"); + } + return dynamic_cast<AbstractGridView &>(*view_); +} + +/* ---------------------------------------------------------------------- */ + +/** + * Helper for only adding layout items for grid items that are actually in view. 3 main functions: + * - #is_item_visible(): Query if an item of a given index is visible in the view (others should be + * skipped when building the layout). + * - #fill_layout_before_visible(): Add empty space to the layout before a visible row is drawn, so + * the layout height is the same as if all items were added (important to get the correct scroll + * height). + * - #fill_layout_after_visible(): Same thing, just adds empty space for after the last visible + * row. + * + * Does two assumptions: + * - Top-to-bottom flow (ymax = 0 and ymin < 0). If that's not good enough, View2D should + * probably provide queries for the scroll offset. + * - Only vertical scrolling. For horizontal scrolling, spacers would have to be added on the + * side(s) as well. + */ +class BuildOnlyVisibleButtonsHelper { + const View2D &v2d_; + const AbstractGridView &grid_view_; + const GridViewStyle &style_; + const int cols_per_row_ = 0; + /* Indices of items within the view. Calculated by constructor */ + IndexRange visible_items_range_{}; + + public: + BuildOnlyVisibleButtonsHelper(const View2D &v2d, + const AbstractGridView &grid_view, + int cols_per_row); + + bool is_item_visible(int item_idx) const; + void fill_layout_before_visible(uiBlock &block) const; + void fill_layout_after_visible(uiBlock &block) const; + + private: + IndexRange get_visible_range() const; + void add_spacer_button(uiBlock &block, int row_count) const; +}; + +BuildOnlyVisibleButtonsHelper::BuildOnlyVisibleButtonsHelper(const View2D &v2d, + const AbstractGridView &grid_view, + const int cols_per_row) + : v2d_(v2d), grid_view_(grid_view), style_(grid_view.get_style()), cols_per_row_(cols_per_row) +{ + visible_items_range_ = get_visible_range(); +} + +IndexRange BuildOnlyVisibleButtonsHelper::get_visible_range() const +{ + int first_idx_in_view = 0; + int max_items_in_view = 0; + + const float scroll_ofs_y = abs(v2d_.cur.ymax - v2d_.tot.ymax); + if (!IS_EQF(scroll_ofs_y, 0)) { + const int scrolled_away_rows = (int)scroll_ofs_y / style_.tile_height; + + first_idx_in_view = scrolled_away_rows * cols_per_row_; + } + + const float view_height = BLI_rctf_size_y(&v2d_.cur); + const int count_rows_in_view = std::max(round_fl_to_int(view_height / style_.tile_height), 1); + max_items_in_view = (count_rows_in_view + 1) * cols_per_row_; + + BLI_assert(max_items_in_view > 0); + return IndexRange(first_idx_in_view, max_items_in_view); +} + +bool BuildOnlyVisibleButtonsHelper::is_item_visible(const int item_idx) const +{ + return visible_items_range_.contains(item_idx); +} + +void BuildOnlyVisibleButtonsHelper::fill_layout_before_visible(uiBlock &block) const +{ + const float scroll_ofs_y = abs(v2d_.cur.ymax - v2d_.tot.ymax); + + if (IS_EQF(scroll_ofs_y, 0)) { + return; + } + + const int scrolled_away_rows = (int)scroll_ofs_y / style_.tile_height; + add_spacer_button(block, scrolled_away_rows); +} + +void BuildOnlyVisibleButtonsHelper::fill_layout_after_visible(uiBlock &block) const +{ + const int last_item_idx = grid_view_.get_item_count() - 1; + const int last_visible_idx = visible_items_range_.last(); + + if (last_item_idx > last_visible_idx) { + const int remaining_rows = (cols_per_row_ > 0) ? + (last_item_idx - last_visible_idx) / cols_per_row_ : + 0; + BuildOnlyVisibleButtonsHelper::add_spacer_button(block, remaining_rows); + } +} + +void BuildOnlyVisibleButtonsHelper::add_spacer_button(uiBlock &block, const int row_count) const +{ + /* UI code only supports button dimensions of `signed short` size, the layout height we want to + * fill may be bigger than that. So add multiple labels of the maximum size if necessary. */ + for (int remaining_rows = row_count; remaining_rows > 0;) { + const short row_count_this_iter = std::min( + std::numeric_limits<short>::max() / style_.tile_height, remaining_rows); + + uiDefBut(&block, + UI_BTYPE_LABEL, + 0, + "", + 0, + 0, + UI_UNIT_X, + row_count_this_iter * style_.tile_height, + nullptr, + 0, + 0, + 0, + 0, + ""); + remaining_rows -= row_count_this_iter; + } +} + +/* ---------------------------------------------------------------------- */ + +class GridViewLayoutBuilder { + uiBlock &block_; + + friend class GridViewBuilder; + + public: + GridViewLayoutBuilder(uiBlock &block); + + void build_from_view(const AbstractGridView &grid_view, const View2D &v2d) const; + + private: + void build_grid_tile(uiLayout &grid_layout, AbstractGridViewItem &item) const; + + uiLayout *current_layout() const; +}; + +GridViewLayoutBuilder::GridViewLayoutBuilder(uiBlock &block) : block_(block) +{ +} + +void GridViewLayoutBuilder::build_grid_tile(uiLayout &grid_layout, + AbstractGridViewItem &item) const +{ + uiLayout *overlap = uiLayoutOverlap(&grid_layout); + + item.add_grid_tile_button(block_); + item.build_grid_tile(*uiLayoutRow(overlap, false)); +} + +void GridViewLayoutBuilder::build_from_view(const AbstractGridView &grid_view, + const View2D &v2d) const +{ + uiLayout *prev_layout = current_layout(); + + uiLayout &layout = *uiLayoutColumn(current_layout(), false); + const GridViewStyle &style = grid_view.get_style(); + + const int cols_per_row = std::max(uiLayoutGetWidth(&layout) / style.tile_width, 1); + + BuildOnlyVisibleButtonsHelper build_visible_helper(v2d, grid_view, cols_per_row); + + build_visible_helper.fill_layout_before_visible(block_); + + /* Use `-cols_per_row` because the grid layout uses a multiple of the passed absolute value for + * the number of columns then, rather than distributing the number of items evenly over rows and + * stretching the items to fit (see #uiLayoutItemGridFlow.columns_len). */ + uiLayout *grid_layout = uiLayoutGridFlow(&layout, true, -cols_per_row, true, true, true); + + int item_idx = 0; + grid_view.foreach_item([&](AbstractGridViewItem &item) { + /* Skip if item isn't visible. */ + if (!build_visible_helper.is_item_visible(item_idx)) { + item_idx++; + return; + } + + build_grid_tile(*grid_layout, item); + item_idx++; + }); + + /* If there are not enough items to fill the layout, add padding items so the layout doesn't + * stretch over the entire width. */ + if (grid_view.get_item_count() < cols_per_row) { + for (int padding_item_idx = 0; padding_item_idx < (cols_per_row - grid_view.get_item_count()); + padding_item_idx++) { + uiItemS(grid_layout); + } + } + + UI_block_layout_set_current(&block_, prev_layout); + + build_visible_helper.fill_layout_after_visible(block_); +} + +uiLayout *GridViewLayoutBuilder::current_layout() const +{ + return block_.curlayout; +} + +/* ---------------------------------------------------------------------- */ + +GridViewBuilder::GridViewBuilder(uiBlock &block) : block_(block) +{ +} + +void GridViewBuilder::build_grid_view(AbstractGridView &grid_view, const View2D &v2d) +{ + grid_view.build_items(); + grid_view.update_from_old(block_); + grid_view.change_state_delayed(); + + GridViewLayoutBuilder builder(block_); + builder.build_from_view(grid_view, v2d); +} + +/* ---------------------------------------------------------------------- */ + +PreviewGridItem::PreviewGridItem(StringRef identifier, StringRef label, int preview_icon_id) + : AbstractGridViewItem(identifier), label(label), preview_icon_id(preview_icon_id) +{ +} + +void PreviewGridItem::build_grid_tile(uiLayout &layout) const +{ + const GridViewStyle &style = get_view().get_style(); + uiBlock *block = uiLayoutGetBlock(&layout); + + uiBut *but = uiDefBut(block, + UI_BTYPE_PREVIEW_TILE, + 0, + label.c_str(), + 0, + 0, + style.tile_width, + style.tile_height, + nullptr, + 0, + 0, + 0, + 0, + ""); + ui_def_but_icon(but, + preview_icon_id, + /* NOLINTNEXTLINE: bugprone-suspicious-enum-usage */ + UI_HAS_ICON | UI_BUT_ICON_PREVIEW); +} + +void PreviewGridItem::set_on_activate_fn(ActivateFn fn) +{ + activate_fn_ = fn; +} + +void PreviewGridItem::set_is_active_fn(IsActiveFn fn) +{ + is_active_fn_ = fn; +} + +void PreviewGridItem::on_activate() +{ + if (activate_fn_) { + activate_fn_(*this); + } +} + +std::optional<bool> PreviewGridItem::should_be_active() const +{ + if (is_active_fn_) { + return is_active_fn_(); + } + return std::nullopt; +} + +} // namespace blender::ui |