image_dilation.hpp

#ifndef PASTELGFX_DILATE_HPP
#define PASTELGFX_DILATE_HPP

#include "pastel/gfx/image_processing/image_dilation.h"

#include "pastel/sys/ensure.h"
#include "pastel/sys/generic/addressof.h"
#include "pastel/sys/view/view_tools.h"
#include "pastel/sys/intersect_alignedbox_alignedbox.h"

namespace Pastel
{

    template <
        typename Element_ConstView,
        typename Image_View>
        void logicOr(
        const ConstView<2, bool, Element_ConstView>& element,
        integer x,
        integer y,
        const View<2, bool, Image_View>& image)
    {
        integer elementWidth = element.width();
        integer elementHeight = element.height();

        integer width = image.width();
        integer height = image.height();

        AlignedBox2i elementWindow(
            x, y, x + elementWidth, y + elementHeight);
        AlignedBox2i imageWindow(
            0, 0, width, height);

        AlignedBox2i clippedWindow;

        if (intersect(elementWindow, imageWindow, clippedWindow))
        {
            clippedWindow.min() -= Vector2i(x, y);
            clippedWindow.max() -= Vector2i(x, y);

            integer clippedWidth = clippedWindow.width();
            integer clippedHeight = clippedWindow.height();

            integer xMinClipped = clippedWindow.min().x();
            integer yMinClipped = clippedWindow.min().y();

            for (integer i = 0;i < clippedHeight;++i)
            {
                for (integer j = 0;j < clippedWidth;++j)
                {
                    if (element(xMinClipped + j, yMinClipped + i))
                    {
                        image(x + j, y + i) = true;
                    }
                }
            }
        }
    }

    template <
        typename Input_ConstView,
        typename Element_ConstView,
        typename Output_View>
        void dilate(
        const ConstView<2, bool, Input_ConstView>& input,
        const ConstView<2, bool, Element_ConstView>& element,
        integer xPivot,
        integer yPivot,
        const View<2, bool, Output_View>& output)
    {
        integer width = input.width();
        integer height = input.height();

        clear(false, output);

        for (integer y = 0;y < height;++y)
        {
            for (integer x = 0;x < width;++x)
            {
                if (input(x, y))
                {
                    logicOr(element, x - xPivot, y - yPivot, output);
                }
            }
        }
    }

}

#endif