Create WRect class.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>

lib/widget.h

@@ -15,6 +15,7 @@ typedef struct WGroup WGroup;
 /* Please note that the first element in all the widgets is a     */
 /* widget variable of type Widget.  We abuse this fact everywhere */
 
+#include "lib/widget/rect.h"
 #include "lib/widget/widget-common.h"
 #include "lib/widget/group.h"
 #include "lib/widget/dialog.h"

lib/widget/Makefile.am

@@ -21,6 +21,7 @@ libmcwidget_la_SOURCES = \
 	mouse.c mouse.h \
 	quick.c quick.h \
 	radio.c radio.h \
+	rect.c rect.h \
 	widget-common.c widget-common.h \
 	wtools.c wtools.h
 

lib/widget/rect.c

@@ -0,0 +1,231 @@
+/* Rectangular class for Midnight Commander widgets
+
+   Copyright (C) 2020
+   The Free Software Foundation, Inc.
+
+   Written by:
+   Andrew Borodin <aborodin@vmail.ru>, 2020
+
+   This file is part of the Midnight Commander.
+
+   The Midnight Commander is free software: you can redistribute it
+   and/or modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the License,
+   or (at your option) any later version.
+
+   The Midnight Commander 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, see <http://www.gnu.org/licenses/>.
+ */
+
+/** \file widget-common.c
+ *  \brief Source: shared stuff of widgets
+ */
+
+#include <config.h>
+
+#include <stdlib.h>
+
+#include "lib/global.h"
+
+#include "rect.h"
+
+/*** global variables ****************************************************************************/
+
+/*** file scope macro definitions ****************************************************************/
+
+/*** file scope type declarations ****************************************************************/
+
+/*** file scope variables ************************************************************************/
+
+/*** file scope functions ************************************************************************/
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Create new WRect object.
+  *
+  * @param y y-coordinate of left-up corner
+  * @param x x-coordinate of left-up corner
+  * @param lines heigth
+  * @param cols width
+  *
+  * @return newly allocated WRect object.
+  */
+
+WRect *
+rect_new (int y, int x, int lines, int cols)
+{
+    WRect *r;
+
+    r = g_try_new (WRect, 1);
+
+    if (r != NULL)
+        rect_init (r, y, x, lines, cols);
+
+    return r;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Initialize WRect object.
+  *
+  * @param r WRect object
+  * @param y y-coordinate of left-up corner
+  * @param x x-coordinate of left-up corner
+  * @param lines heigth
+  * @param cols width
+  */
+
+void
+rect_init (WRect * r, int y, int x, int lines, int cols)
+{
+    r->y = y;
+    r->x = x;
+    r->lines = lines;
+    r->cols = cols;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Change position of rectangle area.
+  *
+  * @param r WRect object
+  * @param dy y-shift of left-up corner
+  * @param dx x-shift of left-up corner
+  */
+
+void
+rect_move (WRect * r, int dy, int dx)
+{
+    r->y += dy;
+    r->x += dx;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Change size of rectangle area.
+  *
+  * @param r WRect object
+  * @param dl change size value of heigth
+  * @param dc change size value of width
+  */
+
+void
+rect_resize (WRect * r, int dl, int dc)
+{
+    r->lines += dl;
+    r->cols += dc;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Calculates the intersection of two rectangle areas.
+  * The resulting rectangle is the largest rectangle which contains intersection of rectangle areas.
+  *
+  * @param r first WRect object
+  * @param r1 second WRect object
+  *
+  * The resulting rectangle is stored in r.
+  */
+
+void
+rect_intersect (WRect * r, const WRect * r1)
+{
+    int y, x;
+    int y1, x1;
+
+    /* right-down corners */
+    y = r->y + r->lines;
+    x = r->x + r->cols;
+    y1 = r1->y + r1->lines;
+    x1 = r1->x + r1->cols;
+
+    /* right-down corner of intersection */
+    y = MIN (y, y1);
+    x = MIN (x, x1);
+
+    /* left-up corner of intersection */
+    r->y = MAX (r->y, r1->y);
+    r->x = MAX (r->x, r1->x);
+
+    /* intersection sizes */
+    r->lines = y - r->y;
+    r->cols = x - r->x;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Calculates the union of two rectangle areas.
+  * The resulting rectangle is the largest rectangle which contains both rectangle areas.
+  *
+  * @param r first WRect object
+  * @param r1 second WRect object
+  *
+  * The resulting rectangle is stored in r.
+  */
+
+void
+rect_union (WRect * r, const WRect * r1)
+{
+    int x, y;
+    int x1, y1;
+
+    /* right-down corners */
+    y = r->y + r->lines;
+    x = r->x + r->cols;
+    y1 = r1->y + r1->lines;
+    x1 = r1->x + r1->cols;
+
+    /* right-down corner of union */
+    y = MAX (y, y1);
+    x = MAX (x, x1);
+
+    /* left-up corner of union */
+    r->y = MIN (r->y, r1->y);
+    r->x = MIN (r->x, r1->x);
+
+    /* union sizes */
+    r->lines = y - r->y;
+    r->cols = x - r->x;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Check whether two rectangle areas are overlapped or not.
+  *
+  * @param r1 WRect object
+  * @param r2 WRect object
+  *
+  * @return TRUE if rectangle areas are overlapped, FALSE otherwise.
+  */
+
+gboolean
+rects_are_overlapped (const WRect * r1, const WRect * r2)
+{
+    return !((r2->x >= r1->x + r1->cols) || (r1->x >= r2->x + r2->cols)
+             || (r2->y >= r1->y + r1->lines) || (r1->y >= r2->y + r2->lines));
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+  * Check whether two rectangle areas are equal or not.
+  *
+  * @param r1 WRect object
+  * @param r2 WRect object
+  *
+  * @return TRUE if rectangle areas are equal, FALSE otherwise.
+  */
+
+gboolean
+rects_are_equal (const WRect * r1, const WRect * r2)
+{
+    return (r1->y == r2->y && r1->x == r2->x && r1->lines == r2->lines && r1->cols == r2->cols);
+}
+
+/* --------------------------------------------------------------------------------------------- */

lib/widget/rect.h

@@ -0,0 +1,44 @@
+
+/** \file rect.h
+ *  \brief Header: rectangular class
+ */
+
+#ifndef MC__WIDGET_RECT_H
+#define MC__WIDGET_RECT_H
+
+/*** typedefs (not structures) and defined constants *********************************************/
+
+#define RECT(x) ((WRect *)(x))
+#define CONST_RECT(x) ((const WRect *)(x))
+
+/*** enums ***************************************************************************************/
+
+/*** structures declarations (and typedefs of structures) ****************************************/
+
+struct WRect;
+typedef struct WRect WRect;
+
+struct WRect
+{
+    int y;
+    int x;
+    int lines;
+    int cols;
+};
+
+/*** global variables defined in .c file *********************************************************/
+
+/*** declarations of public functions ************************************************************/
+
+WRect *rect_new (int y, int x, int lines, int cols);
+void rect_init (WRect * r, int y, int x, int lines, int cols);
+void rect_move (WRect * r, int dy, int dx);
+void rect_resize (WRect * r, int dl, int dc);
+void rect_intersect (WRect * r, const WRect * r1);
+void rect_union (WRect * r, const WRect * r1);
+gboolean rects_are_overlapped (const WRect * r1, const WRect * r2);
+gboolean rects_are_equal (const WRect * r1, const WRect * r2);
+
+/*** inline functions ****************************************************************************/
+
+#endif /* MC__WIDGET_RECT_H */