source: tags/arb_5.2/WINDOW/AW_click.cxx

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
// #include <malloc.h>
#include <X11/X.h>
#include <X11/Xlib.h>

#include <aw_root.hxx>
#include "aw_device.hxx"
#include "aw_commn.hxx"
#include <aw_click.hxx>

using namespace AW;

// *****************************************************************************************
//          device_click
// *****************************************************************************************

AW_device_click::AW_device_click(AW_common *commoni):AW_device(commoni) {
}

void AW_device_click::init(AW_pos mousex,AW_pos mousey, AW_pos max_distance_linei, AW_pos max_distance_texti, AW_pos radi, AW_bitset filteri) {
    AWUSE(radi);
    mouse_x           = mousex;
    mouse_y           = mousey;
    filter            = filteri;
    max_distance_line = max_distance_linei*max_distance_linei;
    max_distance_text = max_distance_texti;
    memset((char *)&opt_line,0,sizeof(opt_line));
    memset((char *)&opt_text,0,sizeof(opt_text));
    opt_line.exists   = false;
    opt_text.exists   = false;
}


AW_DEVICE_TYPE AW_device_click::type(void) {
    return AW_DEVICE_CLICK;
}


/***********************************************************************************************************************/
/* line  text  zoomtext  box *******************************************************************************************/
/***********************************************************************************************************************/

int AW_device_click::line(int gc, AW_pos x0, AW_pos y0, AW_pos x1, AW_pos y1, AW_bitset filteri, AW_CL clientdata1, AW_CL clientdata2) {
    AW_pos X0,Y0,X1,Y1;                             // Transformed pos
    AW_pos CX0,CY0,CX1,CY1;                         // Clipped line
    int    drawflag;                                // is line visible on screen
    AW_pos lx, ly;
    AW_pos dx, dy;
    AW_pos h1, h2;
    AW_pos distance, skalar = 0;
    bool   best_line        = false;             // is this line the best ?

    AWUSE(gc);
    if(!(filteri & filter)) return false;

    this->transform(x0,y0,X0,Y0);
    this->transform(x1,y1,X1,Y1);
    drawflag = this->clip(X0,Y0,X1,Y1,CX0,CY0,CX1,CY1);

    if (drawflag) {
        //stimmen die Kreise um die Punkte ?



        // distance to the second point of the line
        dx       = mouse_x - X1;
        dy       = mouse_y - Y1;
        distance = (dx*dx) + (dy*dy);
        if (distance < max_distance_line) {
            best_line = true;
            max_distance_line = distance;
            //add more comments
            skalar = 0.0;
        }

        // distance to the first point of the line
        dx       = mouse_x - X0;
        dy       = mouse_y - Y0;
        distance = (dx*dx) + (dy*dy);
        if (distance < max_distance_line) {
            best_line = true;
            max_distance_line = distance;
            //add more comments
            skalar = 1.0;
        }

        lx = X1 - X0;
        ly = Y1 - Y0;
        h2 = (lx*lx) + (ly*ly);

        // Punkt darf nicht in der Verlaengerung der Linie liegen
        if (h2 > 0.0000000001){
            skalar = (dx*lx+dy*ly)/h2;
            if ( 0.0 <= skalar && skalar <= 1.0 ) {
                // berechne Trefferpunkt auf Linie
                // distance to the line
                h1       = dx*ly - dy*lx;
                distance = (h1*h1) / h2;
                if (distance < max_distance_line) {
                    best_line         = true;
                    max_distance_line = distance;
                    //add more comments
                }
            }
        }

        if (best_line == true) {
            aw_assert(x0 == x0); aw_assert(x1 == x1); // not NAN
            aw_assert(y0 == y0); aw_assert(y1 == y1);

            opt_line.x0           = x0;
            opt_line.y0           = y0;
            opt_line.x1           = x1;
            opt_line.y1           = y1;
            opt_line.height       = distance;
            opt_line.length       = skalar;
            opt_line.client_data1 = clientdata1;
            opt_line.client_data2 = clientdata2;
            opt_line.exists       = true;
        }
        return true;
    }
    return false;
}


int AW_device_click::text(int gc, const char *str, AW_pos x, AW_pos y, AW_pos alignment, AW_bitset filteri, AW_CL clientdata1, AW_CL clientdata2,long opt_strlen) {
    if(filteri & filter) {
        AW_pos X0,Y0;           // Transformed pos
        this->transform(x,y,X0,Y0);

        XFontStruct *xfs = &common->gcs[gc]->curfont;

        AW_pos Y1 = Y0+(AW_pos)(xfs->max_bounds.descent);
        Y0        = Y0-(AW_pos)(xfs->max_bounds.ascent);

        /***************** Fast check text against top bottom clip ***************************/

        if (this->clip_rect.t == 0) {
            if (Y1 < this->clip_rect.t) return 0;
        }
        else {
            if (Y0 < this->clip_rect.t) return 0;
        }

        if (this->clip_rect.b == common->screen.b) {
            if (Y0 > this->clip_rect.b) return 0;
        }
        else {
            if (Y1 > this->clip_rect.b) return 0;
        }

        /***************** vertical check mouse against textsurrounding  ***************************/

        bool   exact     = true;
        double best_dist = 0;
        
        if (mouse_y > Y1) {     // outside text
            if (mouse_y > Y1+max_distance_text) return 0; // too far above
            exact = false;
            best_dist = mouse_y - Y1;
        }
        else if (mouse_y < Y0) {
            if (mouse_y < Y0-max_distance_text) return 0; // too far below
            exact = false;
            best_dist = Y0 - mouse_y;
        }

        /***************** align text  ***************************/
        int len        = opt_strlen ? opt_strlen : strlen(str);
        int text_width = (int)get_string_size(gc,str,len);

        X0        = common->x_alignment(X0,text_width,alignment);
        AW_pos X1 = X0+text_width;

        /**************** check against left right clipping areas *********/
        if (X1 < this->clip_rect.l) return 0;
        if (X0 > this->clip_rect.r) return 0;

        if (mouse_x < X0) return 0; // left of text
        if (mouse_x > X1) return 0; // right of text

        max_distance_text = best_dist; // exact hit -> distance = 0;

        int position;
        if (xfs->max_bounds.width == xfs->min_bounds.width) {           // monospaced font
            short letter_width = xfs->max_bounds.width;
            position = (int)((mouse_x-X0)/letter_width);
            if (position<0) position = 0;
            if (position>(len-1)) position = len-1;
        }
        else {                                 // non-monospaced font
            AW_GC_Xm *gcm = AW_MAP_GC(gc);
            position   = 0;
            int tmp_offset = 0;
            while (position<=len) {
                tmp_offset += gcm->width_of_chars[(unsigned char)str[position]];
                if (mouse_x <= X0+tmp_offset) break;
                position++;
            }
        }

        AW_pos dist2center = Distance(Position(mouse_x, mouse_y),
                                      LineVector(X0, Y0, X0+text_width, Y1).centroid());

        if (!opt_text.exists || // first candidate
            (!opt_text.exactHit && exact) || // previous candidate was no exact hit
            (dist2center<opt_text.dist2center)) // distance to text-center is smaller
        {
            opt_text.textArea     = Rectangle(rtransform(LineVector(X0, Y0, X1, Y1)));
            opt_text.alignment    = alignment;
            opt_text.rotation     = 0;
            opt_text.distance     = max_distance_text;
            opt_text.dist2center  = dist2center;
            opt_text.cursor       = position;
            opt_text.client_data1 = clientdata1;
            opt_text.client_data2 = clientdata2;
            opt_text.exists       = true;
            opt_text.exactHit     = exact;
        }
    }
    return 1;
}


void AW_device_click::get_clicked_line(class AW_clicked_line *ptr) {
    *ptr = opt_line;
}


void AW_device_click::get_clicked_text(class AW_clicked_text *ptr) {
    *ptr = opt_text;
}

double AW_clicked_line::distanceTo(const AW::Position& pos) {
    AW::LineVector cl(x0, y0, x1, y1);
    if (cl.length() == 0) {
        return AW::Distance(pos, cl.start());
    }
    return AW::Distance(pos, cl);
}

bool AW_getBestClick(const AW::Position& click, AW_clicked_line *cl, AW_clicked_text *ct, AW_CL *cd1, AW_CL *cd2) {
    // detect the nearest item next to 'click'
    // and return that items callback params.
    // returns false, if nothing has been clicked

    AW_clicked_element *bestClick = 0;

    if (cl->exists) {
        if (ct->exists) {
            if (cl->distanceTo(click) < ct->distance) {
                bestClick = cl;
            }
            else {
                bestClick = ct;
            }
        }
        else {
            bestClick = cl;
        }
    }
    else if (ct->exists) {
        bestClick = ct;
    }

    if (bestClick) {
        *cd1 = bestClick->client_data1;
        *cd2 = bestClick->client_data2;
    }
    else {
        *cd1 = 0;
        *cd2 = 0;
    }

    return bestClick;
}