(wip) vaev-driver: Pagination rework.

src/vaev-engine/dom/window.cpp

@@ -82,7 +82,11 @@ export struct Window {
         Font::Database db;
         if (not db.loadSystemFonts())
             logWarn("not all fonts were properly loaded into database");
-        Style::Computer computer{_media, *_document->styleSheets, db};
+        Style::Computer computer{
+            _media,
+            *_document->styleSheets,
+            std::move(db),
+        };
         computer.build();
         computer.styleDocument(*_document);
     }
@@ -96,8 +100,10 @@ export struct Window {
     }
 
     [[clang::coro_wrapper]]
-    Generator<Print::Page> print(Print::Settings const& settings) const {
-        return Driver::print(_document.upgrade(), settings);
+    Generator<Print::Page> print(Print::Settings const& settings) {
+        auto context = Driver::PaginationContext::create(*_document, settings);
+        for (auto p : context.iterPages())
+            co_yield p;
     }
 };
 

src/vaev-engine/driver/render.cpp

@@ -21,11 +21,15 @@ export struct RenderResult {
 };
 
 export RenderResult render(Gc::Ref<Dom::Document> dom, Style::Media const& media, Layout::Viewport viewport) {
-    Font::Database db;
-    if (not db.loadSystemFonts())
+    Font::Database database;
+    if (not database.loadSystemFonts())
         logWarn("not all fonts were properly loaded into database");
 
-    Style::Computer computer{media, *dom->styleSheets, db};
+    Style::Computer computer{
+        media,
+        *dom->styleSheets,
+        std::move(database),
+    };
     computer.build();
     computer.styleDocument(*dom);
 

src/vaev-engine/layout/base/breaks.cpp

@@ -82,6 +82,9 @@ export struct Breakpoint {
     Vec<Opt<Breakpoint>> children = {};
     Advance advance;
 
+    static Breakpoint const START_OF_DOCUMENT;
+    static Breakpoint const END_OF_DOCUMENT;
+
     static Breakpoint forced(usize endIdx) {
         return {
             .endIdx = endIdx,
@@ -171,19 +174,29 @@ export struct Breakpoint {
     }
 };
 
+Breakpoint const Breakpoint::START_OF_DOCUMENT = {
+    .endIdx = 0,
+    .advance = Advance::WITHOUT_CHILDREN
+};
+
+Breakpoint const Breakpoint::END_OF_DOCUMENT = {
+    .endIdx = 1,
+    .advance = Advance::WITHOUT_CHILDREN
+};
+
 export struct BreakpointTraverser {
-    MutCursor<Breakpoint> prevIteration, currIteration;
+    Cursor<Breakpoint> prevIteration, currIteration;
 
     BreakpointTraverser(
-        MutCursor<Breakpoint> prev = nullptr,
-        MutCursor<Breakpoint> curr = nullptr
+        Cursor<Breakpoint> prev = nullptr,
+        Cursor<Breakpoint> curr = nullptr
     ) : prevIteration(prev), currIteration(curr) {}
 
     bool isDeactivated() {
         return prevIteration == nullptr and currIteration == nullptr;
     }
 
-    MutCursor<Breakpoint> traversePrev(usize i, usize j) {
+    Cursor<Breakpoint> traversePrev(usize i, usize j) {
         if (prevIteration and prevIteration->children.len() > 0 and
             (i + 1 == prevIteration->endIdx or
              (prevIteration->advance == Breakpoint::Advance::WITH_CHILDREN and i == prevIteration->endIdx))) {
@@ -193,7 +206,7 @@ export struct BreakpointTraverser {
         return nullptr;
     }
 
-    MutCursor<Breakpoint> traverseCurr(usize i, usize j) {
+    Cursor<Breakpoint> traverseCurr(usize i, usize j) {
         if (currIteration and currIteration->children.len() > 0 and i + 1 == currIteration->endIdx) {
             if (currIteration->children[j])
                 return &currIteration->children[j].unwrap();

src/vaev-engine/layout/base/input.cpp

@@ -26,8 +26,8 @@ export struct Input {
     Vec2Au position = {};
     Vec2Au availableSpace = {};
     Vec2Au containingBlock = {};
-    MutCursor<RunningPositionMap> runningPosition = nullptr;
-    usize pageNumber = 0;
+    MutCursor<Runnings> runningPosition = nullptr;
+    usize pageIndex = 0;
 
     BreakpointTraverser breakpointTraverser = {};
 

src/vaev-engine/layout/base/running-position.cpp

@@ -27,10 +27,11 @@ export struct RunningPositionInfo {
     }
 };
 
-struct RunningPositionMap {
+// Mapping the different Running positions to their respective names and their page.
+struct Runnings {
     Map<CustomIdent, Vec<RunningPositionInfo>> content;
 
-    void add(usize pageNumber, Layout::Box& box) {
+    void add(usize pageNumber, Box& box) {
         auto& style = box.style;
 
         if (auto position = style->position.is<RunningPosition>()) {
@@ -79,7 +80,6 @@ struct RunningPositionMap {
     }
 
     Slice<RunningPositionInfo> _searchPage(Slice<RunningPositionInfo> list, usize page) {
-        page++; // pages are 1-indexed
         // binary search of all running positions that match the page
 
         auto res = search(list, [&](RunningPositionInfo const& info) {

src/vaev-engine/layout/block.cpp

@@ -197,7 +197,7 @@ struct BlockFormatingContext : FormatingContext {
                 .availableSpace = {input.availableSpace.x, 0_au},
                 .containingBlock = {inlineSize, input.knownSize.y.unwrapOr(0_au)},
                 .runningPosition = input.runningPosition,
-                .pageNumber = input.pageNumber,
+                .pageIndex = input.pageIndex,
                 .breakpointTraverser = input.breakpointTraverser.traverseInsideUsingIthChild(i),
                 .pendingVerticalSizes = input.pendingVerticalSizes,
             };

src/vaev-engine/layout/builder/mod.cpp

@@ -828,7 +828,7 @@ export Box buildElement(Gc::Ref<Dom::Element> elt) {
     return box;
 }
 
-export Box buildForPseudoElement(Dom::PseudoElement& el, usize currentPage, RunningPositionMap& runningPos) {
+export Box buildForPseudoElement(Dom::PseudoElement& el, usize currentPage, Runnings& runningPos) {
     auto proseStyle = _proseStyleFromStyle(*el.specifiedValues(), el.specifiedValues()->fontFace);
 
     if (el.specifiedValues()->content.is<String>()) {

src/vaev-engine/layout/flex.cpp

@@ -1454,7 +1454,7 @@ struct FlexFormatingContext : FormatingContext {
                         .position = flexItem.position,
                         .availableSpace = availableSpace,
                         .runningPosition = input.runningPosition,
-                        .pageNumber = input.pageNumber,
+                        .pageIndex = input.pageIndex,
                     }
                 );
                 flexItem.commit(input.fragment);

src/vaev-engine/layout/inline.cpp

@@ -119,7 +119,7 @@ struct InlineFormatingContext : FormatingContext {
                         input.knownSize.y.unwrapOr(0_au)
                     },
                     .runningPosition = input.runningPosition,
-                    .pageNumber = input.pageNumber,
+                    .pageIndex = input.pageIndex,
                 }
             );
         }

src/vaev-engine/layout/positioned.cpp

@@ -65,7 +65,7 @@ export void lookForRunningPosition(Input& input, Box& box) {
 
     if (box.style->position.is<RunningPosition>()) {
         auto& runningMap = input.runningPosition.peek();
-        runningMap.add(input.pageNumber, box);
+        runningMap.add(input.pageIndex, box);
     }
 }
 

src/vaev-engine/style/computer.cpp

@@ -17,7 +17,7 @@ namespace Vaev::Style {
 export struct Computer {
     Media _media;
     StyleSheetList const& _styleBook;
-    Font::Database& fontBook;
+    Font::Database _database;
     StyleRuleLookup _styleRuleLookup{};
 
     // MARK: Cascading ---------------------------------------------------------
@@ -304,7 +304,7 @@ export struct Computer {
                 _evalRule(rule, page, *computed);
 
         for (auto& area : computed->_areas) {
-            auto font = _lookupFontface(fontBook, *area.specifiedValues());
+            auto font = _lookupFontface(_database, *area.specifiedValues());
             area.specifiedValues()->fontFace = font;
         }
 
@@ -323,7 +323,7 @@ export struct Computer {
         if (not parentSpecifiedValues.font.sameInstance(specifiedValues->font) and
             (parentSpecifiedValues.font->families != specifiedValues->font->families or
              parentSpecifiedValues.font->weight != specifiedValues->font->weight)) {
-            auto font = _lookupFontface(fontBook, *specifiedValues);
+            auto font = _lookupFontface(_database, *specifiedValues);
             specifiedValues->fontFace = font;
         } else {
             specifiedValues->fontFace = parentSpecifiedValues.fontFace;
@@ -338,7 +338,7 @@ export struct Computer {
     void styleDocument(Dom::Document& doc) {
         if (auto el = doc.documentElement()) {
             auto rootSpecifiedValues = makeRc<SpecifiedValues>(SpecifiedValues::initial());
-            rootSpecifiedValues->fontFace = _lookupFontface(fontBook, *rootSpecifiedValues);
+            rootSpecifiedValues->fontFace = _lookupFontface(_database, *rootSpecifiedValues);
             styleElement(*rootSpecifiedValues, *el);
         }
         _propagateBodyBackgroundToHtml(doc);
@@ -390,13 +390,13 @@ export struct Computer {
                         }
 
                         // FIXME: use attrs from style::FontFace
-                        if (fontBook.load(resolvedUrl.unwrap()))
+                        if (_database.load(resolvedUrl.unwrap()))
                             break;
 
                         logWarn("Failed to load font {}", ff.family);
                     } else {
                         if (
-                            fontBook.queryExact(src.identifier.unwrap<FontFamily>().name)
+                            _database.queryExact(src.identifier.unwrap<FontFamily>().name)
                         )
                             break;