CCanvas.h

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */
#ifndef CCanvas_H
#define CCanvas_H

#include <mrpt/utils/utils_defs.h>
#include <mrpt/utils/TColor.h>
#include <mrpt/math/eigen_frwds.h>

namespace mrpt
{
namespace utils
{
class CImage;

/** This virtual class defines the interface of any object accepting drawing
 * primitives on it.
 *
 *  A number of text fonts can be selected with CCanvas::selectTextFont(). These
 * are the
 *   implemented font names:
 *
 *  - "6x13"
 *  - "6x13B" (bold)
 *  - "6x13O" (italic)
 *  - "9x15"
 *  - "9x15B" (bold)
 *  - "10x20"
 *  - "18x18ja" (Japanese, UNICODE character values)
 *
 *  For an example of each font check the <a
 * href="http://www.mrpt.org/Implemented_2D_Fonts">corresponding wiki page</a>.
 *
 * \sa CImage
 * \ingroup mrpt_base_grp
 */
class CCanvas
{
   protected:
        /** The selected font name. */
        std::string m_selectedFont;

        /** Direct access to character bitmaps. */
        const uint32_t* m_selectedFontBitmaps;

   public:
        CCanvas();

        /** Definition of pen styles
          */
        enum TPenStyle
        {
                psSolid = 0,
                psDash, /* -------  */
                psDot, /* .......  */
                psDashDot, /* _._._._  */
                psDashDotDot /* _.._.._  */
        };

        /** Dummy virtual destructor:
          */
        virtual ~CCanvas() {}
        /** Changes the value of the pixel (x,y).
          *  Pixel coordinates starts at the left-top corner of the image, and start
         * in (0,0).
          *  The meaning of the parameter "color" depends on the implementation: it
         * will usually
          *   be a 24bit RGB value (0x00RRGGBB), but it can also be just a 8bit gray
         * level.
          *
          *  You can also use a TColor() type as input and it will be automatically
         * converted to size_t.
          *
          *  This method must support (x,y) values OUT of the actual image size
         * without neither
          *   raising exceptions, nor leading to memory access errors.
          *
          */
        virtual void setPixel(int x, int y, size_t color) = 0;

        /** Returns the width of the image in pixels
          */
        virtual size_t getWidth() const = 0;

        /** Returns the height of the image in pixels
          */
        virtual size_t getHeight() const = 0;

        /** Draws a line.
          * \param x0 The starting point x coordinate
          * \param y0 The starting point y coordinate
          * \param x1 The end point x coordinate
          * \param y1 The end point y coordinate
          * \param color The color of the line
          * \param width The desired width of the line (this is IGNORED in this
         * virtual class)
          *  This method may be redefined in some classes implementing this
         * interface in a more appropiate manner.
          */
        virtual void line(
                int x0, int y0, int x1, int y1, const mrpt::utils::TColor color,
                unsigned int width = 1, TPenStyle penStyle = psSolid);

        /** Draws a rectangle (an empty rectangle, without filling)
          * \param x0 The top-left x coordinate
          * \param y0 The top-left y coordinate
          * \param x1 The right-bottom x coordinate
          * \param y1 The right-bottom y coordinate
          * \param color The color of the line
          * \param width The desired width of the line.
          * \sa filledRectangle
          */
        void rectangle(
                int x0, int y0, int x1, int y1, const mrpt::utils::TColor color,
                unsigned int width = 1);

        /*****************************************************AJOGD***************************************************/
        /** Draws a triangle
          * \param x0 The triangle center x coordinate
          * \param y0 The triangle center y coordinate
          * \param size The size of the triangle
          * \param color The color of the line
          *     \param inferior The position of the triangle
          * \param width The desired width of the line.
          * \sa triangle
          */
        void triangle(
                int x0, int y0, int size, const mrpt::utils::TColor color,
                bool inferior = true, unsigned int width = 1);
        /************************************************************************************************************/

        /** Draws a filled rectangle.
          * \param x0 The top-left x coordinate
          * \param y0 The top-left y coordinate
          * \param x1 The right-bottom x coordinate
          * \param y1 The right-bottom y coordinate
          * \param color The color of the rectangle fill
          *  This method may be redefined in some classes implementing this
         * interface in a more appropiate manner.
          * \sa rectangle
          */
        virtual void filledRectangle(
                int x0, int y0, int x1, int y1, const mrpt::utils::TColor color);

        /** Renders 2D text using bitmap fonts.
          * \param x0 The x coordinates
          * \param y0 The y coordinates
          * \param str The string to put. If using UNICODE characters, use UTF-8
         * encoding.
          * \param color The text color
          *
          * \sa selectTextFont
          */
        virtual void textOut(
                int x0, int y0, const std::string& str,
                const mrpt::utils::TColor color);

        /** Select the current font used when drawing text.
          * \param fontName The name of the font
          *
          *  Valid font names:
          *  - 5x7
          *  - 6x13
          *  - 6x13B
          *  - 6x13O
          *  - 9x15   (Default at start-up)
          *  - 9x15B
          *  - 10x20
          *  - 18x18ja (Asian characters for UTF-8 strings - Only available if MRPT
         * is built with MRPT_HAS_ASIAN_FONTS = true)
          *
          *   <img src="sample_textFonts.png" >
          *
          * \sa textOut, The example in <a
         * href="http://www.mrpt.org/Implemented_2D_Fonts">this page</a>.
          */
        virtual void selectTextFont(const std::string& fontName);

        /** Draws an image as a bitmap at a given position.
          * \param x0 The top-left corner x coordinates on this canvas where the
         * image is to be drawn
          * \param y0 The top-left corner y coordinates on this canvas where the
         * image is to be drawn
          * \param img The image to be drawn in this canvas
          *  This method may be redefined in some classes implementing this
         * interface in a more appropiate manner.
          */
        virtual void drawImage(int x, int y, const utils::CImage& img);

        /** Draw a cross.
        * \param x0 The point x coordinate
        * \param y0 The point y coordinate
        * \param color The color of the cross
        * \param size The size of the cross
        * \param type The cross type. It could be: 'x', '+' or ':'(like '+' but
        * clear at the center dot)
        * \param width The desired width of the cross (this is IGNORED yet)
        */
        void cross(
                int x0, int y0, const mrpt::utils::TColor color, char type,
                unsigned int size = 5, unsigned int width = 1);

        /** Draws an image as a bitmap at a given position, with some custom scale
         * and rotation changes.
          * \param x0 The top-left corner x coordinates on this canvas where the
         * image is to be drawn
          * \param y0 The top-left corner y coordinates on this canvas where the
         * image is to be drawn
          * \param rotation The rotation in radians, positive values being
         * anti-clockwise direction, 0 is the normal position.
          * \param scale The scale factor, e.g. 2 means twice the original size.
          * \param img The image to be drawn in this canvas
          *  This method may be redefined in some classes implementing this
         * interface in a more appropiate manner.
          */
        virtual void drawImage(
                int x, int y, const utils::CImage& img, float rotation, float scale);

        /** Draws a circle of a given radius.
          * \param x The center - x coordinate in pixels.
          * \param y The center - y coordinate in pixels.
          * \param radius The radius - in pixels.
          * \param color The color of the circle.
          * \param width The desired width of the line (this is IGNORED in this
         * virtual class)
          */
        virtual void drawCircle(
                int x, int y, int radius,
                const mrpt::utils::TColor& color = mrpt::utils::TColor(255, 255, 255),
                unsigned int width = 1);

        /** Draws an ellipse representing a given confidence interval of a 2D
         * Gaussian distribution.
          * \param mean_x The x coordinate of the center point of the ellipse.
          * \param mean_y The y coordinate of the center point of the ellipse.
          * \param cov2D A 2x2 covariance matrix.
          * \param confIntervalStds How many "sigmas" for the confidence level (i.e.
         * 2->95%, 3=99.97%,...)
          * \param color The color of the ellipse
          * \param width The desired width of the line (this is IGNORED in this
         * virtual class)
          * \param nEllipsePoints The number of points to generate to approximate
         * the ellipse shape.
          * \exception std::exception On an invalid matrix.
          */
        template <class MATRIX2X2>
        void ellipseGaussian(
                const MATRIX2X2* cov2D, const double mean_x, const double mean_y,
                double confIntervalStds = 2,
                const mrpt::utils::TColor& color = mrpt::utils::TColor(255, 255, 255),
                unsigned int width = 1, int nEllipsePoints = 20)
        {
                MRPT_START
                int x1 = 0, y1 = 0, x2 = 0, y2 = 0;
                double ang;
                MATRIX2X2 eigVal, eigVec;
                int i;

                // Compute the eigen-vectors & values:
                cov2D->eigenVectors(eigVec, eigVal);

                eigVal = eigVal.array().sqrt().matrix();
                MATRIX2X2 M;
                M.multiply_ABt(eigVal, eigVec);

                // Compute the points of the 2D ellipse:
                for (i = 0, ang = 0; i < nEllipsePoints;
                         i++, ang += (M_2PI / (nEllipsePoints - 1)))
                {
                        double ccos = cos(ang);
                        double ssin = sin(ang);

                        x2 = round(
                                mean_x + confIntervalStds * (ccos * M(0, 0) + ssin * M(1, 0)));
                        y2 = round(
                                mean_y + confIntervalStds * (ccos * M(0, 1) + ssin * M(1, 1)));

                        if (i > 0) line(x1, y1, x2, y2, color, width);

                        x1 = x2;
                        y1 = y2;
                }  // end for points on ellipse

                MRPT_END_WITH_CLEAN_UP(
                        std::cout << "Covariance matrix leading to error is:" << std::endl
                                          << *cov2D << std::endl;);
        }

        /** Draws a set of marks onto the image, given a generic container of
         * entities having just "x" and "y" fields.
         *  The class of FEATURELIST can be, for example,
         * std::vector<mrpt::math::TPoint2D>, std::vector<TPixelCoordsf> or
         * mrpt::vision::CFeatureList
         * \sa drawFeatures
         */
        template <class FEATURELIST>
        void drawFeaturesSimple(
                const FEATURELIST& list, const TColor& color = TColor::red(),
                const int cross_size = 5)
        {
                for (size_t i = 0; i < list.size(); ++i)
                {
                        const int x = round(list.getFeatureX(i));
                        const int y = round(list.getFeatureY(i));
                        this->cross(x, y, color, '+', cross_size);
                }
        }

        /** Draws a set of marks (or scaled circles for features with scale) onto
         * the image, given a generic container of features.
         *  The class of FEATURELIST can be:
         *    - mrpt::vision::CFeatureList
         *    - mrpt::vision::TSimpleFeatureList
         *
         * \sa drawFeaturesSimple
         */
        template <class FEATURELIST>
        void drawFeatures(
                const FEATURELIST& list, const TColor& color = TColor::red(),
                const bool showIDs = false, const bool showResponse = false)
        {
                for (size_t i = 0; i < list.size(); ++i)
                {
                        const int x = round(list.getFeatureX(i));
                        const int y = round(list.getFeatureY(i));
                        this->cross(x, y, color, '+');
                        if (showIDs)
                                this->textOut(
                                        x, y,
                                        format(
                                                "%u", static_cast<unsigned int>(list.getFeatureID(i))),
                                        TColor::red());
                        if (showResponse)
                                this->textOut(
                                        x, y + 10, format(
                                                                   "R:%u", static_cast<unsigned int>(
                                                                                           list.getFeatureResponse(i))),
                                        TColor::red());
                        if (!list.isPointFeature(i))
                                this->drawCircle(x, y, list.getScale(i), TColor::red());
                }
        }
};  // End of class

}  // end of namespace utils

}  // end of namespace mrpt

#endif