From 64959a85047d3c253692a8afdfb6f467fdb2fa6a Mon Sep 17 00:00:00 2001 From: Andreas Kling Date: Sat, 9 Jul 2022 15:17:47 +0200 Subject: LibWeb: Express intrinsic size layout via size constraints Previously, we had three layout modes: - Normal: - Everything uses the computed values from CSS. - MinContent: - Containing blocks act as if they have 0 width. - All line breaking opportunities are taken. - MaxContent: - Containing blocks act as if they have infinite width. - Only forced line breaks are accepted. The above was based on a set of misunderstandings of CSS sizing. A major problem with the above was that *all* containing blocks behaved differently during intrinsic size layout, not just the relevant one. With this patch there are only two layout modes: - Normal: - Everything uses the computed values from CSS. - IntrinsicSizeDetermination: - One or more boxes have size constraints applied. There are two size constraints per layout box, set here: - FormattingState::NodeState::width_constraint - FormattingState::NodeState::height_constraint They are of type SizeConstraint and can be one of None, MinContent, or MaxContent. The default is None. When performing an IntrinsicSizeDetermination layout, we now assign a size constraint to the box we're trying to determine the intrinsic size of, which is then honored by using two new helpers to query the dimensions of containing blocks: - FormattingContext::containing_block_width_for(Box) - FormattingContext::containing_block_height_for(Box) If there's a relevant constraint in effect on the Box, the size of its containing block is adjusted accordingly. This is essentially an implementation of the "available space" constraints from CSS-SIZING-3. I'm sure some things will break from this, and we'll have to deal with that separately. Spec: https://drafts.csswg.org/css-sizing-3/#available --- Userland/Libraries/LibWeb/Layout/LineBuilder.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'Userland/Libraries/LibWeb/Layout/LineBuilder.h') diff --git a/Userland/Libraries/LibWeb/Layout/LineBuilder.h b/Userland/Libraries/LibWeb/Layout/LineBuilder.h index 0f28cfeb81..8efdbc2e42 100644 --- a/Userland/Libraries/LibWeb/Layout/LineBuilder.h +++ b/Userland/Libraries/LibWeb/Layout/LineBuilder.h @@ -23,9 +23,9 @@ public: void append_text_chunk(TextNode const&, size_t offset_in_node, size_t length_in_node, float leading_size, float trailing_size, float leading_margin, float trailing_margin, float content_width, float content_height); // Returns whether a line break occurred. - bool break_if_needed(LayoutMode layout_mode, float next_item_width) + bool break_if_needed(float next_item_width) { - if (should_break(layout_mode, next_item_width)) { + if (should_break(next_item_width)) { break_line(); return true; } @@ -45,7 +45,7 @@ public: private: void begin_new_line(bool increment_y); - bool should_break(LayoutMode, float next_item_width); + bool should_break(float next_item_width); LineBox& ensure_last_line_box(); -- cgit v1.2.3