ladybird/Userland/Libraries/LibWeb/Painting/ScrollFrame.h

/*
 * Copyright (c) 2024, Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <LibWeb/PixelUnits.h>

namespace Web::Painting {

struct ScrollFrame : public RefCounted<ScrollFrame> {
    i32 id { -1 };
    CSSPixelPoint cumulative_offset;
    CSSPixelPoint own_offset;
};

}
LibWeb: Make AddClipRect display list item account for scroll offset Before this change AddClipRect was a "special" because it didn't respect scroll frame offset and was meant to be recorded using viewport-relative coordinates. The motivation behind this was to record a "final" clip rectangle computed by intersecting all clip rectangles used by a clip frame. The disadvantage of this approach is that it blocks us from implementing an optimisation to reuse display list if the only change is in the scroll offset, because any scroll offset change leads to invalidating all AddClipRect items within a list. This change aligns AddClipRect with the rest of display list items by making it account for scroll frame offset. It required discontinuing the recording of the intersection of all clip rectangles within a clip frame and instead producing an AddClipRect for each of them. A nice side effect is the removal of code that shifts clip rectangle by `enclosing_scroll_offset()` in a bunch of places, because now it happens automatically in `DisplayList::apply_scroll_offsets()`. 2024-08-10 14:24:25 +02:00			`/*`
			`* Copyright (c) 2024, Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>`
			`*`
			`* SPDX-License-Identifier: BSD-2-Clause`
			`*/`

			`#pragma once`

			`#include <LibWeb/PixelUnits.h>`

			`namespace Web::Painting {`

			`struct ScrollFrame : public RefCounted<ScrollFrame> {`
			`i32 id { -1 };`
LibWeb: Rename offset to cumulative_offset in ScrollFrame New name reflects that offset is not just a frame's own offset but a sum of offsets from containing block chain. 2024-08-17 18:11:07 +02:00			`CSSPixelPoint cumulative_offset;`
LibWeb: Update scroll thumb position by mutating display list A new display list item type named PaintScrollBar is introduced. Having a dedicated type for scroll bars allows the thumb position to be updated without rebuilding a display list. This was not possible with FillRectWithRoundedCorners that does not allow to tell whether it belongs to scroll thumb. 2024-08-17 18:56:56 +02:00			`CSSPixelPoint own_offset;`
LibWeb: Make AddClipRect display list item account for scroll offset Before this change AddClipRect was a "special" because it didn't respect scroll frame offset and was meant to be recorded using viewport-relative coordinates. The motivation behind this was to record a "final" clip rectangle computed by intersecting all clip rectangles used by a clip frame. The disadvantage of this approach is that it blocks us from implementing an optimisation to reuse display list if the only change is in the scroll offset, because any scroll offset change leads to invalidating all AddClipRect items within a list. This change aligns AddClipRect with the rest of display list items by making it account for scroll frame offset. It required discontinuing the recording of the intersection of all clip rectangles within a clip frame and instead producing an AddClipRect for each of them. A nice side effect is the removal of code that shifts clip rectangle by `enclosing_scroll_offset()` in a bunch of places, because now it happens automatically in `DisplayList::apply_scroll_offsets()`. 2024-08-10 14:24:25 +02:00			`};`

			`}`