[chaz/tint2] / src / util / area.c

/**************************************************************************
*
* Tint2 : area
*
* Copyright (C) 2008 thierry lorthiois (lorthiois@bbsoft.fr) from Omega distribution
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
**************************************************************************/

#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xatom.h>
#include <X11/extensions/Xrender.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pango/pangocairo.h>

#include "area.h"
#include "server.h"
#include "panel.h"


/************************************************************
 * !!! This design is experimental and not yet fully implemented !!!!!!!!!!!!!
 * 
 * DATA ORGANISATION :
 * Areas in tint2 are similar to widgets in a GUI. 
 * All graphical objects (panel, taskbar, task, systray, clock, ...) 'inherit' an abstract class 'Area'.
 * This class 'Area' manage the background, border, size, position and padding.
 * Area is at the begining of each object (&object == &area).
 * 
 * tint2 define one panel per monitor. And each panel have a tree of Area.
 * The root of the tree is Panel.Area. And task, clock, systray, taskbar,... are nodes.
 * 
 * The tree give the localisation of each object :
 * - tree's root is in the background while tree's leafe are foreground objects
 * - position of a node/Area depend on the layout : parent's position (posx, posy), size of previous brothers and parent's padding
 * - size of a node/Area depend on the content (SIZE_BY_CONTENT objects) or on the layout (SIZE_BY_LAYOUT objects) 
 * 
 * DRAWING AND LAYERING ENGINE :
 * Redrawing an object (like the clock) could come from an 'external event' (date change) 
 * or from a 'layering event' (position change).
 * The following 'drawing engine' take care of :
 * - posx/posy of all Area
 * - 'layering event' propagation between object
 * 1) browse tree SIZE_BY_CONTENT
 *  - resize SIZE_BY_CONTENT node : children are resized before parent
 *      - if 'size' changed then 'resize = 1' on the parent
 * 2) browse tree SIZE_BY_LAYOUT and POSITION
 *  - resize SIZE_BY_LAYOUT node : parent is resized before children
 *  - calculate position (posx,posy) : parent is calculated before children
 *      - if 'position' changed then 'redraw = 1'
 * 3) browse tree REDRAW
 *  - redraw needed objects : parent is drawn before children
 *
 * CONFIGURE PANEL'S LAYOUT :
 * 'panel_items' parameter (in config) define the list and the order of nodes in tree's panel.
 * 'panel_items = SC' define a panel with just Systray and Clock.
 * So the tree 'Panel.Area' will have 2 childs (Systray and Clock).
 *
 ************************************************************/

void init_rendering(void *obj, int pos)
{
        Area *a = (Area*)obj;
        
        // initialize fixed position/size
        GSList *l;
        for (l = a->list; l ; l = l->next) {
                Area *child = ((Area*)l->data);
                if (panel_horizontal) {
                        child->posy = pos + a->bg->border.width + a->paddingy;
                        child->height = a->height - (2 * (a->bg->border.width + a->paddingy));
                        init_rendering(child, child->posy);
                }
                else {
                        child->posx = pos + a->bg->border.width + a->paddingy;
                        child->width = a->width - (2 * (a->bg->border.width + a->paddingy));
                        init_rendering(child, child->posx);
                }
        }
}


void rendering(void *obj)
{
        Panel *panel = (Panel*)obj;

        size_by_content(&panel->area);
        size_by_layout(&panel->area, 0, 1);
        
        refresh(&panel->area);
}


void size_by_content (Area *a)
{
        // don't resize hiden objects
        if (!a->on_screen) return;

        // children node are resized before its parent
        GSList *l;
        for (l = a->list; l ; l = l->next)
                size_by_content(l->data);
        
        // calculate area's size
        a->on_changed = 0;
        if (a->resize && a->size_mode == SIZE_BY_CONTENT) {
                a->resize = 0;

                if (a->_resize) {
                        if (a->_resize(a)) {
                                // 'size' changed => 'resize = 1' on the parent
                                ((Area*)a->parent)->resize = 1;
                                a->on_changed = 1;
                        }
                }
        }
}


void size_by_layout (Area *a, int pos, int level)
{
        // don't resize hiden objects
        if (!a->on_screen) return;

        // parent node is resized before its children
        // calculate area's size
        GSList *l;
        if (a->resize && a->size_mode == SIZE_BY_LAYOUT) {
                a->resize = 0;

                if (a->_resize) {
                        a->_resize(a);
                        // resize childs with SIZE_BY_LAYOUT
                        for (l = a->list; l ; l = l->next) {
                                Area *child = ((Area*)l->data);
                                if (child->size_mode == SIZE_BY_LAYOUT && child->list)
                                        child->resize = 1;
                        }
                }
        }

        // update position of childs
        pos += a->paddingxlr + a->bg->border.width;
        int i=0;
        for (l = a->list; l ; l = l->next) {
                Area *child = ((Area*)l->data);
                if (!child->on_screen) continue;
                i++;
                
                if (panel_horizontal) {
                        if (pos != child->posx) {
                                // pos changed => redraw
                                child->posx = pos;
                                child->on_changed = 1;
                        }
                }
                else {
                        if (pos != child->posy) {
                                // pos changed => redraw
                                child->posy = pos;
                                child->on_changed = 1;
                        }
                }
                
                /*// position of each visible object
                int k;
                for (k=0 ; k < level ; k++) printf("  ");
                printf("tree level %d, object %d, pos %d, %s\n", level, i, pos, (child->size_mode == SIZE_BY_LAYOUT) ? "SIZE_BY_LAYOUT" : "SIZE_BY_CONTENT");*/
                size_by_layout(child, pos, level+1);
                
                if (panel_horizontal)
                        pos += child->width + a->paddingx;
                else
                        pos += child->height + a->paddingx;
        }       

        if (a->on_changed) {
                // pos/size changed
                a->redraw = 1;
                if (a->_on_change_layout)
                        a->_on_change_layout (a);
        }
}


void refresh (Area *a)
{
        // don't draw and resize hide objects
        if (!a->on_screen) return;

        // don't draw transparent objects (without foreground and without background)
        if (a->redraw) {
                a->redraw = 0;
                // force redraw of child
                //GSList *l;
                //for (l = a->list ; l ; l = l->next)
                        //((Area*)l->data)->redraw = 1;

                //printf("draw area posx %d, width %d\n", a->posx, a->width);
                draw(a);
        }

        // draw current Area
        if (a->pix == 0) printf("empty area posx %d, width %d\n", a->posx, a->width);
        XCopyArea (server.dsp, a->pix, ((Panel *)a->panel)->temp_pmap, server.gc, 0, 0, a->width, a->height, a->posx, a->posy);

        // and then refresh child object
        GSList *l;
        for (l = a->list; l ; l = l->next)
                refresh(l->data);
}


int resize_by_layout(void *obj, int maximum_size)
{
        Area *child, *a = (Area*)obj;
        int size, nb_by_content=0, nb_by_layout=0;

        if (panel_horizontal) {         
                // detect free size for SIZE_BY_LAYOUT's Area
                size = a->width - (2 * (a->paddingxlr + a->bg->border.width));
                GSList *l;
                for (l = a->list ; l ; l = l->next) {
                        child = (Area*)l->data;
                        if (child->on_screen && child->size_mode == SIZE_BY_CONTENT) {
                                size -= child->width;
                                nb_by_content++;
                        }
                        if (child->on_screen && child->size_mode == SIZE_BY_LAYOUT)
                                nb_by_layout++;
                }
                //printf("  resize_by_layout Deb %d, %d\n", nb_by_content, nb_by_layout);
                if (nb_by_content+nb_by_layout)
                        size -= ((nb_by_content+nb_by_layout-1) * a->paddingx);

                int width=0, modulo=0, old_width;
                if (nb_by_layout) {
                        width = size / nb_by_layout;
                        modulo = size % nb_by_layout;
                        if (width > maximum_size && maximum_size != 0) {
                                width = maximum_size;
                                modulo = 0;
                        }
                }

                // resize SIZE_BY_LAYOUT objects
                for (l = a->list ; l ; l = l->next) {
                        child = (Area*)l->data;
                        if (child->on_screen && child->size_mode == SIZE_BY_LAYOUT) {
                                old_width = child->width;
                                child->width = width;
                                if (modulo) {
                                        child->width++;
                                        modulo--;
                                }
                                if (child->width != old_width)
                                        child->on_changed = 1;
                        }
                }
        }
        else {
                // detect free size for SIZE_BY_LAYOUT's Area
                size = a->height - (2 * (a->paddingxlr + a->bg->border.width));
                GSList *l;
                for (l = a->list ; l ; l = l->next) {
                        child = (Area*)l->data;
                        if (child->on_screen && child->size_mode == SIZE_BY_CONTENT) {
                                size -= child->height;
                                nb_by_content++;
                        }
                        if (child->on_screen && child->size_mode == SIZE_BY_LAYOUT)
                                nb_by_layout++;
                }
                if (nb_by_content+nb_by_layout)
                        size -= ((nb_by_content+nb_by_layout-1) * a->paddingx);

                int height=0, modulo=0, old_height;
                if (nb_by_layout) {
                        height = size / nb_by_layout;
                        modulo = size % nb_by_layout;
                        if (height > maximum_size && maximum_size != 0) {
                                height = maximum_size;
                                modulo = 0;
                        }
                }

                // resize SIZE_BY_LAYOUT objects
                for (l = a->list ; l ; l = l->next) {
                        child = (Area*)l->data;
                        if (child->on_screen && child->size_mode == SIZE_BY_LAYOUT) {
                                old_height = child->height;
                                child->height = height;
                                if (modulo) {
                                        child->height++;
                                        modulo--;
                                }
                                if (child->height != old_height)
                                        child->on_changed = 1;
                        }
                }
        }
        return 0;
}


void set_redraw (Area *a)
{
        a->redraw = 1;

        GSList *l;
        for (l = a->list ; l ; l = l->next)
                set_redraw(l->data);
}

void hide(Area *a)
{
        Area *parent = (Area*)a->parent;

        a->on_screen = 0;
        parent->resize = 1;
        if (panel_horizontal)
                a->width = 0;
        else
                a->height = 0;
}

void show(Area *a)
{
        Area *parent = (Area*)a->parent;

        a->on_screen = 1;
        parent->resize = 1;
        a->resize = 1;
}

void draw (Area *a)
{
        if (a->pix) XFreePixmap (server.dsp, a->pix);
        a->pix = XCreatePixmap (server.dsp, server.root_win, a->width, a->height, server.depth);

        // add layer of root pixmap (or clear pixmap if real_transparency==true)
        if (server.real_transparency)
                clear_pixmap(a->pix, 0 ,0, a->width, a->height);
        XCopyArea (server.dsp, ((Panel *)a->panel)->temp_pmap, a->pix, server.gc, a->posx, a->posy, a->width, a->height, 0, 0);

        cairo_surface_t *cs;
        cairo_t *c;

        cs = cairo_xlib_surface_create (server.dsp, a->pix, server.visual, a->width, a->height);
        c = cairo_create (cs);

        draw_background (a, c);

        if (a->_draw_foreground)
                a->_draw_foreground(a, c);

        cairo_destroy (c);
        cairo_surface_destroy (cs);
}


void draw_background (Area *a, cairo_t *c)
{
        if (a->bg->back.alpha > 0.0) {
                //printf("    draw_background (%d %d) RGBA (%lf, %lf, %lf, %lf)\n", a->posx, a->posy, pix->back.color[0], pix->back.color[1], pix->back.color[2], pix->back.alpha);
                draw_rect(c, a->bg->border.width, a->bg->border.width, a->width-(2.0 * a->bg->border.width), a->height-(2.0*a->bg->border.width), a->bg->border.rounded - a->bg->border.width/1.571);
                cairo_set_source_rgba(c, a->bg->back.color[0], a->bg->back.color[1], a->bg->back.color[2], a->bg->back.alpha);
                cairo_fill(c);
        }

        if (a->bg->border.width > 0 && a->bg->border.alpha > 0.0) {
                cairo_set_line_width (c, a->bg->border.width);

                // draw border inside (x, y, width, height)
                draw_rect(c, a->bg->border.width/2.0, a->bg->border.width/2.0, a->width - a->bg->border.width, a->height - a->bg->border.width, a->bg->border.rounded);
                /*
                // convert : radian = degre * M_PI/180
                // definir le degrade dans un carre de (0,0) (100,100)
                // ensuite ce degrade est extrapoler selon le ratio width/height
                // dans repere (0, 0) (100, 100)
                double X0, Y0, X1, Y1, degre;
                // x = X * (a->width / 100), y = Y * (a->height / 100)
                double x0, y0, x1, y1;
                X0 = 0;
                Y0 = 100;
                X1 = 100;
                Y1 = 0;
                degre = 45;
                // et ensuite faire la changement d'unite du repere
                // car ce qui doit reste inchangee est les traits et pas la direction

                // il faut d'abord appliquer une rotation de 90 (et -180 si l'angle est superieur a  180)
                // ceci peut etre applique une fois pour toute au depart
                // ensuite calculer l'angle dans le nouveau repare
                // puis faire une rotation de 90
                x0 = X0 * ((double)a->width / 100);
                x1 = X1 * ((double)a->width / 100);
                y0 = Y0 * ((double)a->height / 100);
                y1 = Y1 * ((double)a->height / 100);

                x0 = X0 * ((double)a->height / 100);
                x1 = X1 * ((double)a->height / 100);
                y0 = Y0 * ((double)a->width / 100);
                y1 = Y1 * ((double)a->width / 100);

                cairo_pattern_t *linpat;
                linpat = cairo_pattern_create_linear (x0, y0, x1, y1);
                cairo_pattern_add_color_stop_rgba (linpat, 0, a->border.color[0], a->border.color[1], a->border.color[2], a->border.alpha);
                cairo_pattern_add_color_stop_rgba (linpat, 1, a->border.color[0], a->border.color[1], a->border.color[2], 0);
                cairo_set_source (c, linpat);
                */
                cairo_set_source_rgba (c, a->bg->border.color[0], a->bg->border.color[1], a->bg->border.color[2], a->bg->border.alpha);

                cairo_stroke (c);
                //cairo_pattern_destroy (linpat);
        }
}


void remove_area (Area *a)
{
        Area *parent = (Area*)a->parent;

        parent->list = g_slist_remove(parent->list, a);
        set_redraw (parent);

}


void add_area (Area *a)
{
        Area *parent = (Area*)a->parent;

        parent->list = g_slist_append(parent->list, a);
        set_redraw (parent);

}


void free_area (Area *a)
{
        GSList *l0;
        for (l0 = a->list; l0 ; l0 = l0->next)
                free_area (l0->data);

        if (a->list) {
                g_slist_free(a->list);
                a->list = 0;
        }
        if (a->pix) {
                XFreePixmap (server.dsp, a->pix);
                a->pix = 0;
        }
}


void draw_rect(cairo_t *c, double x, double y, double w, double h, double r)
{
        if (r > 0.0) {
                double c1 = 0.55228475 * r;

                cairo_move_to(c, x+r, y);
                cairo_rel_line_to(c, w-2*r, 0);
                cairo_rel_curve_to(c, c1, 0.0, r, c1, r, r);
                cairo_rel_line_to(c, 0, h-2*r);
                cairo_rel_curve_to(c, 0.0, c1, c1-r, r, -r, r);
                cairo_rel_line_to (c, -w +2*r, 0);
                cairo_rel_curve_to (c, -c1, 0, -r, -c1, -r, -r);
                cairo_rel_line_to (c, 0, -h + 2 * r);
                cairo_rel_curve_to (c, 0, -c1, r - c1, -r, r, -r);
        }
        else
                cairo_rectangle(c, x, y, w, h);
}


void clear_pixmap(Pixmap p, int x, int y, int w, int h)
{
        Picture pict = XRenderCreatePicture(server.dsp, p, XRenderFindVisualFormat(server.dsp, server.visual), 0, 0);
        XRenderColor col = { .red=0, .green=0, .blue=0, .alpha=0 };
        XRenderFillRectangle(server.dsp, PictOpSrc, pict, &col, x, y, w, h);
        XRenderFreePicture(server.dsp, pict);
}