brush.h

#pragma once
 
#include "sdl_painter/color.h"
#include "sdl_painter/geometry.h"
 
#include <cstdint>
 
namespace sdl_painter {
 
enum class BrushType : uint8_t {
  kSolid,   
  kLinear,  
  kRadial,  
};
 
class Brush {
 public:
  Brush() = default;
 
  explicit Brush(const Color& color) : mColor(color) {}
 
  [[nodiscard]] static Brush LinearGradient(const Point& start,
                                            const Point& end, const Color& from,
                                            const Color& to) noexcept {
    Brush b;
    b.mType = BrushType::kLinear;
    b.mColor = from;
    b.mColor2 = to;
    b.mStart = start;
    b.mEnd = end;
    return b;
  }
 
  [[nodiscard]] static Brush RadialGradient(const Point& center, float radius,
                                            const Color& from,
                                            const Color& to) noexcept {
    Brush b;
    b.mType = BrushType::kRadial;
    b.mColor = from;
    b.mColor2 = to;
    b.mStart = center;
    b.mRadius = radius;
    return b;
  }
 
  [[nodiscard]] BrushType GetType() const noexcept { return mType; }
 
  [[nodiscard]] bool IsGradient() const noexcept {
    return mType != BrushType::kSolid;
  }
 
  [[nodiscard]] const Color& GetColor2() const noexcept { return mColor2; }
 
  [[nodiscard]] const Point& GetStart() const noexcept { return mStart; }
 
  [[nodiscard]] const Point& GetEnd() const noexcept { return mEnd; }
 
  [[nodiscard]] float GetRadius() const noexcept { return mRadius; }
 
  [[nodiscard]] const Color& GetColor() const noexcept { return mColor; }
 
  void SetColor(const Color& color) noexcept { mColor = color; }
 
  [[nodiscard]] bool IsVisible() const noexcept {
    return mColor.a > 0 || (IsGradient() && mColor2.a > 0);
  }
 
  [[nodiscard]] bool operator==(const Brush& other) const noexcept {
    if (mColor != other.mColor || mType != other.mType) {
      return false;
    }
    if (mType == BrushType::kSolid) {
      return true;
    }
    return mColor2 == other.mColor2 && mStart.x == other.mStart.x &&
           mStart.y == other.mStart.y && mEnd.x == other.mEnd.x &&
           mEnd.y == other.mEnd.y && mRadius == other.mRadius;
  }
  [[nodiscard]] bool operator!=(const Brush& other) const noexcept {
    return !(*this == other);
  }
 
  [[nodiscard]] static Brush NoBrush() noexcept {
    return Brush(Color::Transparent());
  }
 
 private:
  Color mColor{Color::Black()};
  Color mColor2{Color::White()};
  Point mStart;
  Point mEnd;
  float mRadius{0.0F};
  BrushType mType{BrushType::kSolid};
};
 
}  // namespace sdl_painter