MapLibreParticleLab/include/llmr/style/properties.hpp

#ifndef LLMR_STYLE_PROPERTIES
#define LLMR_STYLE_PROPERTIES

#include <array>
#include <vector>
#include <string>
#include <limits>
#include <set>
#include <type_traits>

#include <boost/optional.hpp>

namespace llmr {

// Stores a premultiplied color, with all four channels ranging from 0..1
typedef std::array<float, 4> Color;

struct PropertyTransition {
    uint16_t duration = 0;
    uint16_t delay = 0;
};

enum class TransitionablePropertyKey {
    Translate = 1,
    FillColor = 2,
    StrokeColor = 3,
    Opacity = 4,
    Width = 5,
    Offset = 6,
    Color = 7,
    DashArray = 8,
    Radius = 9,
    Blur = 10,
    Halo = 11,
    HaloRadius = 12,
    HaloBlur = 13,
};

enum class Winding {
    EvenOdd = 1,
    NonZero = 2
};

// enum LineCap {
//     Round = 1
// };

// enum LineJoin {
//     Butt = 1,
//     Bevel = 2
// };

enum class Property {
    Null = 1,
    Constant = 2,
    Stops = 3,
    Linear = 4
};

enum class TranslateAnchor : uint8_t {
    Map = 1,
    Viewport = 2
};

namespace functions {

float null(float z, const std::vector<float>&);
float constant(float z, const std::vector<float>& values);
float min(float z, const std::vector<float>& values);
float max(float z, const std::vector<float>& values);
float stops(float z, const std::vector<float>& values);
float linear(float z, const std::vector<float>& values);
float exponential(float z, const std::vector<float>& values);

}

struct FunctionProperty {
    typedef float (*fn)(float z, const std::vector<float>& values);

    fn function;
    std::vector<float> values;

    inline FunctionProperty() : function(&functions::null) {}
    inline FunctionProperty(float value) : function(&functions::constant), values(1, value) {}
    template <typename T> inline T evaluate(float z) const { return function(z, values); }
};

struct GenericClass {
    boost::optional<FunctionProperty> enabled;
    boost::optional<std::array<FunctionProperty, 2>> translate;
    boost::optional<PropertyTransition> translate_transition;
    boost::optional<TranslateAnchor> translateAnchor;
    boost::optional<FunctionProperty> opacity;
    boost::optional<PropertyTransition> opacity_transition;
    boost::optional<bool> prerender;
    boost::optional<float> prerenderBuffer;
    boost::optional<uint16_t> prerenderSize;
    boost::optional<uint16_t> prerenderBlur;
};

struct GenericProperties {
    bool enabled = true;
    std::array<float, 2> translate = {{ 0, 0 }};
    TranslateAnchor translateAnchor = TranslateAnchor::Map;
    float opacity = 1.0;
    bool prerender = false;
    float prerenderBuffer = 1.0f / 32.0f;
    uint16_t prerenderSize = 256;
    uint16_t prerenderBlur = 0;

    virtual bool isVisible() const {
        if (!enabled) { return false; }
        if (opacity <= 0) { return false; }
        return true;
    }
};

struct IconClass : public GenericClass {
    boost::optional<FunctionProperty> size;
    boost::optional<Color> color;
    boost::optional<PropertyTransition> color_transition;
    boost::optional<std::string> image;
    boost::optional<FunctionProperty> radius;
    boost::optional<PropertyTransition> radius_transition;
    boost::optional<FunctionProperty> blur;
    boost::optional<PropertyTransition> blur_transition;
};

struct IconProperties : public GenericProperties {
    float size = 0;
    Color color = {{ 1, 1, 1, 1 }};
    std::string image;
    float radius = 0;
    float blur = 0;
};

struct LineClass : public GenericClass {
    boost::optional<FunctionProperty> width;
    boost::optional<PropertyTransition> width_transition;
    boost::optional<FunctionProperty> offset;
    boost::optional<PropertyTransition> offset_transition;
    boost::optional<Color> color;
    boost::optional<PropertyTransition> color_transition;
    boost::optional<std::array<FunctionProperty, 2>> dash_array;
    boost::optional<PropertyTransition> dash_array_transition;
};

struct LineProperties : public GenericProperties {
    float width = 0;
    float offset = 0;
    Color color = {{ 0, 0, 0, 1 }};
    std::array<float, 2> dash_array = {{ 1, -1 }};
};

struct FillClass : public GenericClass {
    boost::optional<Winding> winding;
    boost::optional<FunctionProperty> antialias;
    boost::optional<Color> fill_color;
    boost::optional<PropertyTransition> fill_color_transition;
    boost::optional<Color> stroke_color;
    boost::optional<PropertyTransition> stroke_color_transition;
    boost::optional<std::string> image;
};

struct FillProperties : public GenericProperties {
    Winding winding = Winding::NonZero;
    bool antialias = true;
    Color fill_color = {{ 0, 0, 0, 1 }};
    Color stroke_color = {{ 0, 0, 0, 1 }};
    float blur = 0.0f;
    std::string image;
};

struct TextClass : public GenericClass {
    boost::optional<Color> color;
    boost::optional<PropertyTransition> color_transition;
    boost::optional<Color> halo;
    boost::optional<PropertyTransition> halo_transition;
    boost::optional<FunctionProperty> halo_radius;
    boost::optional<PropertyTransition> halo_radius_transition;
    boost::optional<FunctionProperty> halo_blur;
    boost::optional<PropertyTransition> halo_blur_transition;
    boost::optional<FunctionProperty> size;
    boost::optional<FunctionProperty> rotate;
    boost::optional<FunctionProperty> always_visible;
};

struct TextProperties : public GenericProperties {
    Color color = {{ 0, 0, 0, 1 }};
    Color halo = {{ 1, 1, 1, 0.75 }};
    float halo_radius = 0.25f;
    float halo_blur = 1.0f;
    float size = 12.0f;
    float rotate = 0.0f;
    bool always_visible = false;
};

struct BackgroundClass : public GenericClass {
    boost::optional<Color> color;
    boost::optional<PropertyTransition> color_transition;
};

struct BackgroundProperties : public GenericProperties {
    Color color = {{ 1, 1, 1, 1 }};
};

struct RasterClass : public GenericClass {
};

struct RasterProperties : public GenericProperties {
};

struct CompositeClass : public GenericClass {
};

struct CompositeProperties : public GenericProperties {
    inline CompositeProperties() : GenericProperties() {}
};


const CompositeProperties defaultCompositeProperties;

}


namespace std {

template <> struct hash<llmr::TransitionablePropertyKey> {
public:
    inline size_t operator()(llmr::TransitionablePropertyKey prop) const {
        typedef typename std::underlying_type<llmr::TransitionablePropertyKey>::type type;
        return std::hash<type>()(static_cast<type>(prop));
    }
};

}

#endif