Curve.h

/*
 * Gamedev Framework (gf)
 * Copyright (C) 2016-2021 Julien Bernard
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
 *    appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 */
#ifndef GF_CURVE_H
#define GF_CURVE_H

#include <cstddef>

#include "GraphicsApi.h"
#include "Rect.h"
#include "Transformable.h"
#include "Vector.h"
#include "VertexArray.h"
#include "VertexBuffer.h"

namespace gf {
#ifndef DOXYGEN_SHOULD_SKIP_THIS
inline namespace v1 {
#endif

  class GF_GRAPHICS_API Curve : public Transformable {
  public:
    enum Type {
      Simple,   
      Outlined, 
    };

    Curve();

    void setType(Type type);

    Type getType() const noexcept {
      return m_type;
    }

    void setColor(const Color4f& color);

    const Color4f& getColor() const {
      return m_color;
    }

    void setWidth(float width);

    float getWidth() const {
      return m_width;
    }

    void setOutlineColor(const Color4f& color);

    const Color4f& getOutlineColor() const {
      return m_outlineColor;
    }

    void setOutlineThickness(float thickness);

    float getOutlineThickness() const {
      return m_outlineThickness;
    }

    virtual std::size_t getPointCount() const = 0;

    virtual Vector2f getPoint(std::size_t index) const = 0;

    RectF getLocalBounds() const;

    void setAnchor(Anchor anchor);

    VertexBuffer commitGeometry() const;

    VertexBuffer commitOutlineGeometry() const;

    virtual void draw(RenderTarget& target, const RenderStates& states) override;

  protected:
    void updateGeometry();

    void setClosed(bool closed = true);

  private:
    void updateColors();
    void updateOutline();
    void updateOutlineColors();

    void computeVertices(VertexArray& vertices, float halfWidth);
  private:
    Type m_type;
    bool m_closed;

    Color4f m_color;
    float m_width;
    VertexArray m_vertices;
    RectF m_bounds;

    Color4f m_outlineColor;
    float m_outlineThickness;
    VertexArray m_outlineVertices;
  };

#ifndef DOXYGEN_SHOULD_SKIP_THIS
}
#endif
}

#endif // GF_CURVE_H