_pen.h

Go to the documentation of this file.

/* === S T A R T =========================================================== */

#ifndef __ETL__PEN_H
#define __ETL__PEN_H

/* === H E A D E R S ======================================================= */

#include "_curve_func.h"
#include <cassert>
#include <iterator>
#include <algorithm>

/* === M A C R O S ========================================================= */

/* === T Y P E D E F S ===================================================== */

/* === C L A S S E S & S T R U C T S ======================================= */

_ETL_BEGIN_NAMESPACE

template<typename T>
class generic_pen_row_iterator
{
public:
    struct iterator_category : public std::random_access_iterator_tag {};
    typedef T value_type;
    typedef int difference_type;
    typedef value_type* pointer;
    typedef value_type& reference;

    typedef generic_pen_row_iterator<value_type> self_type;

    pointer data_;
    int pitch_;

    reference operator[](int i)const { assert(data_); return *(pointer)( (char*)data_+pitch_*i ); }
    reference operator*()const { assert(data_); return *data_; }
    pointer operator->() const { assert(data_); return &(operator*()); }

    void inc() { assert(data_); data_ = (pointer)((char*)data_ + pitch_); }
    void inc(int n) { assert(data_); data_ = (pointer)((char*)data_ + n*pitch_); }

    void dec() { assert(data_); data_ = (pointer)((char*)data_ - pitch_); }
    void dec(int n) { assert(data_); data_ = (pointer)((char*)data_ - n*pitch_); }

    const self_type &operator++() { assert(data_); inc(); return *this; }
    const self_type &operator--() { assert(data_); dec(); return *this; }

    self_type operator++(int)
        { assert(data_); self_type ret(*this); inc(); return ret; }
    self_type operator--(int)
        { assert(data_); self_type ret(*this); dec(); return ret; }

    bool operator==(const self_type &rhs)const
        { return data_==rhs.data_; }

    bool operator!=(const self_type &rhs)const
        { return data_!=rhs.data_; }

    difference_type operator-(const self_type &rhs)const
        { assert(data_); return ((char*)data_-(char*)rhs.data_-1)/pitch_+1; }

    self_type operator+(const difference_type &rhs)const
    {
        assert(data_);
        self_type ret(*this);
        ret.inc(rhs);
        return ret;
    }

    self_type operator-(const difference_type &rhs)const
    {
        assert(data_);
        self_type ret(*this);
        ret.dec(rhs);
        return ret;
    }

    operator const generic_pen_row_iterator<const value_type>()const
    {
        return generic_pen_row_iterator<const value_type>(data_,pitch_);
    }

    operator bool()const { return (bool)data_; }
    bool operator!()const { return !data_; }

    generic_pen_row_iterator(pointer data, int pitch):data_(data),pitch_(pitch) { }
    generic_pen_row_iterator():data_(NULL) { }
};

template<typename T, typename AT=T>
class generic_pen
{
public:
    typedef T value_type;
    typedef AT accumulator_type;
    typedef value_type* pointer;
    typedef accumulator_type* accumulator_pointer;
    typedef const value_type* const_pointer;
    typedef const accumulator_type* const_accumulator_pointer;
    typedef value_type& reference;
    typedef const value_type& const_reference;

    typedef pointer iterator_x;
    typedef const_pointer const_iterator_x;

    typedef generic_pen_row_iterator<value_type> iterator_y;
    typedef generic_pen_row_iterator<const value_type> const_iterator_y;

    struct difference_type
    {
        typedef int value_type;
        value_type x,y;
        difference_type(value_type x, value_type y):x(x),y(y) { }
        value_type &operator[](int i)const { return i?y:x; }
    };

protected:
    int x_,y_;
    int w_,h_;
private:
    int pitch_;
    value_type value_;
    value_type *data_;

    typedef generic_pen<T,AT> self_type;

    void addptr(int nbytes)
    {
        data_ = (pointer)((char*)data_ + nbytes);
    }

    void subptr(int nbytes)
    {
        data_ = (pointer)((char*)data_ - nbytes);
    }

public:

    generic_pen(value_type *data, int w, int h, int pitch):
        x_(0),
        y_(0),
        w_(w),
        h_(h),
        pitch_(pitch),
        data_(data)
    {
    }

    generic_pen(value_type *data, int w, int h):
        x_(0),
        y_(0),
        w_(w),
        h_(h),
        pitch_(sizeof(value_type)*w),
        data_(data)
    {
    }

    generic_pen():data_(NULL) { }

    self_type& move(int a, int b)
    {
        assert(data_);
        x_ += a, y_ += b;
        addptr(b*pitch_ + a*sizeof(value_type));
        return *this;
    }
    self_type& move_to(int x, int y) { assert(data_); return move(x - x_,y - y_);}
    void set_value(const value_type &v) { value_=v; }

    void inc_x() { assert(data_); x_++; data_++; }
    void dec_x() { assert(data_); x_--; data_--; }
    void inc_y() { assert(data_); y_++; addptr(pitch_); }
    void dec_y() { assert(data_); y_--; subptr(pitch_); }

    void inc_x(int n) { assert(data_); x_+=n; data_+=n; }
    void dec_x(int n) { assert(data_); x_-=n; data_-=n; }
    void inc_y(int n) { assert(data_); y_+=n; data_ = (pointer)((char*)data_ + pitch_*n); }
    void dec_y(int n) { assert(data_); y_-=n; data_ = (pointer)((char*)data_ - pitch_*n); }

    void put_value(const value_type &v)const { assert(data_); *data_=v; }
    void put_value()const { assert(data_); put_value(value_); }

    void put_value_clip(const value_type &v)const
        { if(!clipped()) put_value(v); }
    void put_value_clip()const { put_value_clip(value_); }

    const_reference get_value()const { assert(data_); return *data_; }

    const_reference get_value_at(int x, int y)const { assert(data_); return ((pointer)(((char*)data_)+y*pitch_))[x]; }

    const_reference get_value_clip_at(int x, int y)const { assert(data_); if(clipped(x,y))return value_type(); return ((pointer)(((char*)data_)+y*pitch_))[x]; }

    const value_type get_value_clip()const { assert(data_); if(clipped())return value_type(); return *data_; }

    const value_type get_pen_value()const { return value_; }

    void put_hline(int l,const value_type &v)
    {for(;l>0;l--,inc_x())put_value(v);}

    void put_hline(int l) {put_hline(l,value_);}

    void put_hline_clip(int l, const value_type &v)
    {l=std::min(l,w_-x_);for(;l>0;l--,inc_x())put_value_clip(v);}

    void put_hline_clip(int l) {put_hline_clip(l,value_);}

    //the put_block functions do not modify the pen
    void put_block(int h, int w, const value_type &v)
    {
        self_type row(*this);
        for(;h>0;h--,row.inc_y())
        {
            self_type col(row);
            col.put_hline(w,v);
        }
    }

    void put_block(int h, int w) { put_block(h,w,value_); }

    void put_block_clip(int h, int w, const value_type &v)
    {
        self_type row(*this);

        //clip start position
        if(row.x_ < 0) { w+=row.x_; row.inc_x(-row.x_); }
        if(row.y_ < 0) { h+=row.y_; row.inc_y(-row.y_); }

        //clip width and height of copy rect
        h = std::min(h,h_-y_);
        w = std::min(w,w_-x_);

        //copy rect
        for(;h>0;h--,row.inc_y())
        {
            self_type col(row);
            col.put_hline(w,v); //already clipped
        }
    }

    void put_block_clip(int h, int w) { put_block(h,w,value_); }


    iterator_x operator[](int i)const { assert(data_); return (pointer)(((char*)data_)+i*pitch_); }

    iterator_x x() { assert(data_); return data_; }
    iterator_x begin_x() { assert(data_); return data_-x_; }
    iterator_x end_x() { assert(data_); return data_-x_+w_; }

    iterator_y y() { assert(data_); return iterator_y(data_,pitch_); }
    iterator_y begin_y() { assert(data_); return iterator_y((pointer)((char*)data_ - y_*pitch_),pitch_); }
    iterator_y end_y() { assert(data_); return iterator_y((pointer)((char*)data_ + (h_-y_)*pitch_),pitch_); }

    operator bool()const { return (bool)data_; }
    bool operator!()const { return !data_; }
    bool operator==(const self_type &rhs)const { return data_==rhs.data_; }
    bool operator!=(const self_type &rhs)const { return data_!=rhs.data_; }
    bool clipped(int x, int y)const { return !(x_+x>=0 && y_+y>=0 && x_+x<w_ && y_+y<h_); }
    bool clipped()const { return !(x_>=0 && y_>=0 && x_<w_ && y_<h_); }

    difference_type operator-(const self_type &rhs)const
    {
        assert(data_);
        assert(pitch_==rhs.pitch_);
        int ptr_diff=(char*)data_-(char*)rhs.data_-1;
        return difference_type(ptr_diff%pitch_/sizeof(value_type)+1,ptr_diff/pitch_);
    }

    self_type operator+(const difference_type &rhs)const
    {
        assert(data_);
        self_type ret(*this);
        ret.move(rhs.x,rhs.y);
        return ret;
    }

    difference_type diff_begin()const {return difference_type(-x_,-y_);}
    difference_type diff_end()const {return difference_type(w_-x_,h_-y_);}

    self_type get_start()const  {return *this + diff_begin(); }
    self_type get_end()const    {return *this + diff_end(); }

    int get_width()const {return w_;}
    int get_height()const {return h_;}

    int get_w()const {return w_;}
    int get_h()const {return h_;}
    int get_pitch()const {return pitch_;}
};

template <
    typename PEN_,
    typename A_=float,
    class AFFINE_=affine_combo<typename PEN_::value_type,A_>
>
class alpha_pen : public PEN_
{
public:
    typedef A_ alpha_type;
    typedef AFFINE_ affine_func_type;

    typedef typename PEN_::value_type value_type;
    typedef alpha_pen self_type;

private:
    alpha_type alpha_;

protected:
    affine_func_type affine_func_;

public:
    using PEN_::get_value;
    using PEN_::get_pen_value;
    using PEN_::inc_x;
    using PEN_::dec_x;
    using PEN_::inc_y;
    using PEN_::dec_y;
    using PEN_::clipped;
    using PEN_::w_;
    using PEN_::h_;
    using PEN_::x_;
    using PEN_::y_;

    alpha_pen(const alpha_type &a = 1, const affine_func_type &func = affine_func_type()):alpha_(a),affine_func_(func) { }
    alpha_pen(const PEN_ &x, const alpha_type &a=1, const affine_func_type &func=affine_func_type())
        :PEN_(x),alpha_(a),affine_func_(func) { }

    const alpha_type& get_alpha()const { return alpha_; }
    void get_alpha(alpha_type &a) const { a=alpha_; }
    void set_alpha(alpha_type a) { alpha_=a; }

    void put_value(const value_type &v, alpha_type a=1)const
        { PEN_::put_value(affine_func_(get_value(),v,alpha_*a)); }
    void put_value()const { put_value(get_pen_value()); }
    void put_value_alpha(alpha_type a)const { put_value(get_pen_value(),a); }
    void put_hline(int l, const alpha_type &a = 1){for(;l>0;l--,inc_x())put_value_alpha(a);}

    void put_value_clip(const value_type &v, alpha_type a=1)const
        { if(!clipped())PEN_::put_value(affine_func_(get_value(),v,alpha_*a)); }
    void put_value_clip()const { put_value_clip(get_pen_value()); }
    void put_value_clip_alpha(alpha_type a)const { put_value_clip(get_pen_value(),a); }
    void put_hline_clip(int l, const alpha_type &a = 1){l=std::min(l,w_-x_);for(;l>0;l--,inc_x())put_value_clip_alpha(a);}

    //the put_block functions do not modify the pen
    void put_block(int h, int w, const alpha_type &a = 1)
    {
        self_type row(*this);
        for(;h>0;h--,row.inc_y())
        {
            self_type col(row);
            col.put_hline(w,a);
        }
    }

    void put_block_clip(int h, int w, const alpha_type &a = 1)
    {
        self_type row(*this);

        //clip start position
        if(row.x_ < 0) { w+=row.x_; row.inc_x(-row.x_); }
        if(row.y_ < 0) { h+=row.y_; row.inc_y(-row.y_); }

        //clip width and height of copy rect
        h = std::min(h,h_-y_);
        w = std::min(w,w_-x_);

        //copy rect
        for(;h>0;h--,row.inc_y())
        {
            self_type col(row);
            col.put_hline(w,a); //already clipped
        }
    }
};

_ETL_END_NAMESPACE

/* === E X T E R N S ======================================================= */

/* === E N D =============================================================== */

#endif