carousel_keylines.hpp

#pragma once
 
#include "qml_material/carousel/carousel_strategy.hpp"
 
namespace qml_material
{
 
struct Keyline {
    qreal offset     = 0; // center position in viewport (main axis)
    qreal size       = 0;
    int   size_class = 2;
};
 
struct KeylineList {
    QVector<Keyline> keylines;
    qreal            scroll_step = 0;
    qreal            large_size  = 0;
    qreal            medium_size = 0;
    qreal            small_size  = 0;
};
 
class CarouselKeylines {
public:
    static auto buildList(const CarouselLayoutInput& input) -> KeylineList;
    static auto layoutItems(const CarouselLayoutInput& input, const KeylineList& keylines)
        -> CarouselLayoutOutput;
};
 
namespace CarouselHeroKeylines
{
 
enum class HeroPhase
{
    Leading,
    Middle,
    Trailing,
};
 
struct HeroMetrics {
    bool  single_item         = false;
    qreal small_leading       = 0;
    qreal small_center        = 0;
    qreal large_leading       = 0;
    qreal large_center        = 0;
    qreal medium_leading      = 0;
    qreal medium_center       = 0;
    qreal scroll_step_leading = 0;
    qreal scroll_step_center  = 0;
};
 
auto computeMetrics(const CarouselLayoutInput& in) -> HeroMetrics;
auto phaseKeylines(const CarouselLayoutInput& in, HeroPhase phase, bool keep_leading_peek)
    -> KeylineList;
void computeHeroSnapOffsets(CarouselLayoutOutput& out, const CarouselLayoutInput& in,
                            bool keep_leading_peek);
auto keepLeadingPeek(const CarouselLayoutInput& in) -> bool;
 
} // namespace CarouselHeroKeylines
 
} // namespace qml_material