CUAnchoredLayout.h

//
//  CUAnchoredLayout.h
//  Cornell University Game Library (CUGL)
//
//  This module provides an support for an anchored layout.  An anchored layout
//  attaches a child node to one of nine "anchors" in the parent (corners, sides
//  or middle), together with a percentage (or absolute) offset.  As the parent
//  grows or shinks, the child will move according to its anchor.  For example,
//  nodes in the center will stay centered, while nodes on the left side will
//  move to keep the appropriate distance from the left side.
//
//  This class uses our standard shared-pointer architecture.
//
//  1. The constructor does not perform any initialization; it just sets all
//     attributes to their defaults.
//
//  2. All initialization takes place via init methods, which can fail if an
//     object is initialized more than once.
//
//  3. All allocation takes place via static constructors which return a shared
//     pointer.
//
//
//  CUGL MIT License:
//      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.
//
//  Author: Walker White and Enze Zhou
//  Version: 1/8/18
//
#ifndef __CU_ANCHORED_LAYOUT_H__
#define __CU_ANCHORED_LAYOUT_H__
#include <cugl/2d/layout/CULayout.h>
#include <unordered_map>
 
namespace  cugl {
class AnchoredLayout : public Layout {
protected:
    class Entry {
    public:
        float x_offset;
        float y_offset;
        Anchor anchor;
        bool absolute;
    };
    
    std::unordered_map<std::string,Entry> _entries;
    
#pragma mark -
#pragma mark Constructors
public:
    AnchoredLayout() {}
    
    ~AnchoredLayout() { dispose(); }
    
    virtual bool initWithData(const std::shared_ptr<JsonValue>& data) override { return true; }
    
    virtual void dispose() override { _entries.clear(); }
 
    static std::shared_ptr<AnchoredLayout> alloc() {
        std::shared_ptr<AnchoredLayout> result = std::make_shared<AnchoredLayout>();
        return (result->init() ? result : nullptr);
    }
    
    static std::shared_ptr<AnchoredLayout> allocWithData(const std::shared_ptr<JsonValue>& data) {
        std::shared_ptr<AnchoredLayout> result = std::make_shared<AnchoredLayout>();
        return (result->initWithData(data) ? result : nullptr);
    }
    
#pragma mark Layout
 
    virtual bool add(const std::string key, const std::shared_ptr<JsonValue>& data) override;
    
    bool addAbsolute(const std::string key, Anchor anchor, const Vec2& offset);
 
    bool addRelative(const std::string key, Anchor anchor, const Vec2& offset);
 
    virtual bool remove(const std::string key) override;
    
    virtual void layout(Node* node) override;
 
};
 
}
#endif /* __CU_ANCHORED_LAYOUT_H__ */