* hyper/: De-pamphletize.

1 files changed, 706 insertions, 0 deletions

diff --git a/src/hyper/scrollbar.c b/src/hyper/scrollbar.c
new file mode 100644
index 00000000..734054aa
--- /dev/null
+++ b/src/hyper/scrollbar.c
@@ -0,0 +1,706 @@
+/*
+  Copyright (C) 1991-2002, The Numerical Algorithms Group Ltd.
+  All rights reserved.
+  Copyright (C) 2007-2008, Gabriel Dos Reis.
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are
+  met:
+
+      - Redistributions of source code must retain the above copyright
+        notice, this list of conditions and the following disclaimer.
+
+      - Redistributions in binary form must reproduce the above copyright
+        notice, this list of conditions and the following disclaimer in
+        the documentation and/or other materials provided with the
+        distribution.
+
+      - Neither the name of The Numerical Algorithms Group Ltd. nor the
+        names of its contributors may be used to endorse or promote products
+        derived from this software without specific prior written permission.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+  PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+  OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/******************************************************************************
+ *
+ * scrollbar.c:  HyperDoc Scrollbar routines
+ *
+ * Copyright The Numerical Algorithms Group Limited 1991, 1992, 1993.
+ *
+ ****************************************************************************/
+#define _SCROLLBAR_C
+#include "axiom-c-macros.h"
+#include "useproto.h"
+#include "debug.h"
+
+#include "extent.h"
+#include "display.h"
+#include "group.h"
+#include "initx.h"
+#include "scrollbar.h"
+#include "parse.h"
+
+#include "all_hyper_proto.H1"
+
+/*************************************************************************
+  Scrollbar Comments                                    10/08/89
+
+  The scrollbar is displayed on the side of the HyperDoc display, if needed.
+  It is composed of four windows
+
+  fScrollUpWindow --  the arrowed box at the top of the scrollbar. Scrolls the
+  window up a line at a time.
+  fScrollDownWindow --  Located at the bottom of the window, it is used to scroll
+  down a single line at a time.
+  scrollbar -- this is the window which does the variable scrolling. It
+  houses the actual scroller.
+  scroller -- This is the scroller inside the scroll bar.
+
+  The procedure below, makes all these windows, and also makes three bitmaps,
+  sup -- The up arrow for the fScrollUpWindow.
+  sdown -- the down arrow for the fScrollDownWindow.
+  scroller -- the scroller stipple.
+  It then fills the window with the proper Pixmap background.
+
+  The scrollbar and scroller works as follows. The size of the scroller is
+  calculated as
+
+  size of scroller            size of visible text
+  -----------------  ===  ------------------------------  .
+  size of scrollbar       size of whole scrolling region
+
+  The top of the scroller shows the relative position in the page of
+  the top of the scrolling region. This way the user knows how far
+  down the page he or she has moved.
+  When the user clicks in the scrollbar, the center of the
+  scroller, if possible, is placed at the point of the click.
+
+  See the routines
+  showScrollBars --  to see how the scroll bars are actually realized.
+  moveScroller --  to see how the scroller is moved when the user scrolls
+
+
+  **************************************************************************/
+
+#ifndef _NO_PROTO
+static int  ch(int height);
+static void changeWindowBackgroundPixmap(Window window, Pixmap pixmap);
+#else
+static int  ch();
+static void changeWindowBackgroundPixmap();
+#endif
+
+static Pixmap sup = 0, sdown = 0, sup_pressed = 0, sdown_pressed = 0, scroller = 0, scrollbar_pix = 0;
+
+
+/* #undef BITMAPS2D to get old style 2d effect */
+
+#ifdef BITMAPS2D
+
+#define CONTROLS_3D 0
+
+#include "sdown.bitmap"
+#include "sup.bitmap"
+
+#define BACKCOLOR gBackgroundColor
+#define FORECOLOR gActiveColor
+
+#else
+
+#define CONTROLS_3D 1
+
+#include "sdown3d.bitmap"
+#include "sdown3dpr.bitmap"
+
+#include "sup3d.bitmap"
+#include "sup3dpr.bitmap"
+
+#define sup_width  sup3d_width
+#define sup_height sup3d_height
+#define sup_bits sup3d_bits
+
+#define sdown_width  sdown3d_width
+#define sdown_height sdown3d_height
+#define sdown_bits   sdown3d_bits
+
+#define BACKCOLOR gControlBackgroundColor
+#define FORECOLOR gControlForegroundColor
+
+#endif
+
+
+#if 0
+#define scroller_width 3
+#define scroller_height 3
+static char scroller_bits[] = {0x05, 0x07, 0x03};
+
+#endif
+
+#define scroller_width 2
+#define scroller_height 2
+static char scroller_bits[] = {
+                               0x01, 0x02};
+
+
+
+static int supheight = sup_height;
+static int supwidth = sup_width;
+
+#define scrollbar_pix_width 3
+#define scrollbar_pix_height 3
+static char scrollbar_pix_bits[] = {0x00, 0x03, 0x00};
+
+
+
+int gScrollbarWidth = sup_width + 2;
+
+
+
+void
+makeScrollBarWindows(void)
+{
+    XSetWindowAttributes at;
+
+    at.cursor = gActiveCursor;
+    at.event_mask = ButtonPress;
+    /** create the bitmaps **/
+    if (supwidth != sdown_width || supheight != sdown_height) {
+        fprintf(stderr,
+                "Scrollbar error, up and down pointers must have the same dimensions\n");
+        exit(-1);
+    }
+
+    if (sup == 0)
+        sup = XCreatePixmapFromBitmapData(
+                                          gXDisplay,
+                                    RootWindow(gXDisplay, gXScreenNumber),
+                                          sup_bits, supwidth, supheight,
+                                          FORECOLOR, BACKCOLOR,
+                                 DefaultDepth(gXDisplay, gXScreenNumber));
+
+    if (sdown == 0)
+        sdown = XCreatePixmapFromBitmapData(
+                                            gXDisplay,
+                                    RootWindow(gXDisplay, gXScreenNumber),
+                                      sdown_bits, sdown_width, sdown_height,
+                                            FORECOLOR, BACKCOLOR,
+                                 DefaultDepth(gXDisplay, gXScreenNumber));
+
+    if (CONTROLS_3D) {
+        sup_pressed = XCreatePixmapFromBitmapData(
+                                                  gXDisplay,
+                                    RootWindow(gXDisplay, gXScreenNumber),
+                                sup3dpr_bits, sup3dpr_width, sup3dpr_height,
+                                                  FORECOLOR, BACKCOLOR,
+                                 DefaultDepth(gXDisplay, gXScreenNumber));
+        sdown_pressed = XCreatePixmapFromBitmapData(
+                                                    gXDisplay,
+                                    RootWindow(gXDisplay, gXScreenNumber),
+                          sdown3dpr_bits, sdown3dpr_width, sdown3dpr_height,
+                                                    FORECOLOR, BACKCOLOR,
+                                 DefaultDepth(gXDisplay, gXScreenNumber));
+    }
+
+    gWindow->fScrollUpWindow = XCreateSimpleWindow(gXDisplay, gWindow->fMainWindow,
+                                                1, 1, supwidth, supheight,
+                                                gWindow->border_width,
+                                                gBorderColor,
+                                                BACKCOLOR);
+
+    gWindow->fScrollDownWindow = XCreateSimpleWindow(gXDisplay, gWindow->fMainWindow,
+                                            1, 1, sdown_width, sdown_height,
+                                                  gWindow->border_width,
+                                                  gBorderColor,
+                                                  BACKCOLOR);
+
+    gWindow->scrollbar = XCreateSimpleWindow(gXDisplay, gWindow->fMainWindow,
+                                              1, 1, 1, 1,
+                                              gWindow->border_width,
+                                              gBorderColor,
+                                              BACKCOLOR);
+    gWindow->scroller = XCreateSimpleWindow(gXDisplay, gWindow->scrollbar,
+                                             1, 1, 1, 1, 0,
+                                             gBorderColor,
+                                             BACKCOLOR);
+
+#ifdef DEBUG
+    fprintf(stderr, "Changing Window Attributes in scrollbar.c #2\n");
+#endif
+
+    at.background_pixmap = sup;
+    XChangeWindowAttributes(gXDisplay, gWindow->fScrollUpWindow,
+                            CWBackPixmap | CWEventMask | CWCursor, &at);
+
+    at.background_pixmap = sdown;
+    XChangeWindowAttributes(gXDisplay, gWindow->fScrollDownWindow,
+                            CWBackPixmap | CWEventMask | CWCursor, &at);
+
+    XChangeWindowAttributes(gXDisplay, gWindow->scrollbar,
+                            CWEventMask | CWCursor, &at);
+
+
+    if (scroller == 0)
+        scroller = XCreatePixmapFromBitmapData(gXDisplay,
+                                    RootWindow(gXDisplay, gXScreenNumber),
+                                               scroller_bits, scroller_width,
+                                               scroller_height,
+                                               FORECOLOR,
+                                               BACKCOLOR,
+                                 DefaultDepth(gXDisplay, gXScreenNumber));
+    if (scrollbar_pix == 0)
+        scrollbar_pix = XCreatePixmapFromBitmapData(gXDisplay,
+                                    RootWindow(gXDisplay, gXScreenNumber),
+                                                    scrollbar_pix_bits,
+                                                    scrollbar_pix_width,
+                                                    scrollbar_pix_height,
+                                                    FORECOLOR,
+                                                    BACKCOLOR,
+                                 DefaultDepth(gXDisplay, gXScreenNumber));
+
+    at.background_pixmap = scroller;
+    XChangeWindowAttributes(gXDisplay, gWindow->scroller,
+                            CWBackPixmap | CWCursor, &at);
+    at.background_pixmap = scrollbar_pix;
+    XChangeWindowAttributes(gXDisplay, gWindow->scrollbar,
+                            CWBackPixmap, &at);
+}
+
+static void
+drawScroller3DEffects(HDWindow * hdWindow, int x1, int y1, int x2, int y2)
+{
+    XClearWindow(gXDisplay, hdWindow->scroller);
+
+    /* draw right "black" line */
+
+    XDrawLine(gXDisplay, hdWindow->scroller, hdWindow->fControlGC,
+              x2 - 3, y1 + 2, x2 - 3, y2 - 3);
+
+    /* draw bottom "black" line */
+
+    XDrawLine(gXDisplay, hdWindow->scroller, hdWindow->fControlGC,
+              x1 + 2, y2 - 3, x2 - 3, y2 - 3);
+
+    /* flip foreground and background colors */
+
+    XSetBackground(gXDisplay, hdWindow->fControlGC, gControlForegroundColor);
+    XSetForeground(gXDisplay, hdWindow->fControlGC, gControlBackgroundColor);
+
+    /* draw top "white" line */
+
+    XDrawLine(gXDisplay, hdWindow->scroller, hdWindow->fControlGC,
+              x1 + 2, y1 + 2, x2 - 3, y1 + 2);
+
+    /* draw left "white" line */
+
+    XDrawLine(gXDisplay, hdWindow->scroller, hdWindow->fControlGC,
+              x1 + 2, y1 + 2, x1 + 2, y2 - 3);
+
+    /* reset colors */
+
+    XSetBackground(gXDisplay, hdWindow->fControlGC, gControlBackgroundColor);
+    XSetForeground(gXDisplay, hdWindow->fControlGC, gControlForegroundColor);
+}
+
+void
+showScrollBars(HDWindow * hdWindow)
+{
+    XWindowChanges wc;
+    /*int src_x = 0, src_y = 0;*/
+    /*unsigned int width = supwidth, height = supheight;*/
+    /*int dest_x = 0, dest_y = 0;*/
+
+    /* see if we even need scroll bars */
+
+    if (hdWindow->page->scrolling->height <= hdWindow->scrollheight)
+        return;
+
+    wc.x = hdWindow->scrollx;
+    wc.y = hdWindow->scrollupy;
+    wc.height = supheight;
+    wc.width = supwidth;
+    XConfigureWindow(gXDisplay, hdWindow->fScrollUpWindow, CWX | CWY | CWHeight
+                     | CWWidth, &wc);
+    wc.y = hdWindow->scrolldowny;
+    XConfigureWindow(gXDisplay, hdWindow->fScrollDownWindow,
+                     CWX | CWY | CWHeight | CWWidth,
+                     &wc);
+    wc.height = hdWindow->fScrollBarHeight;
+    wc.y = hdWindow->scrollbary;
+    XConfigureWindow(gXDisplay, hdWindow->scrollbar,
+                     CWX | CWY | CWHeight | CWWidth,
+                     &wc);
+    wc.x = 0;
+    wc.y = hdWindow->fScrollerTopPos;
+    wc.width = supwidth;
+    wc.height = hdWindow->fScrollerHeight;
+    XConfigureWindow(gXDisplay, hdWindow->scroller,
+                     CWX | CWY | CWHeight | CWWidth,
+                     &wc);
+
+    /*
+     * Now we map the windows, since the bitmaps are the backgrounds for the
+     * windows, we need to worry about redrawing them.
+     */
+
+    XMapWindow(gXDisplay, hdWindow->fScrollUpWindow);
+    XMapWindow(gXDisplay, hdWindow->fScrollDownWindow);
+    XMapWindow(gXDisplay, hdWindow->scrollbar);
+    XMapWindow(gXDisplay, hdWindow->scroller);
+
+    drawScroller3DEffects(hdWindow, 0, 0, wc.width, wc.height);
+}
+
+
+/************************************************************************
+
+  Moves the scroller to its proper place within the scrollbar. It
+  calculates how far down the page we are, and then moves the scroller
+  accordingly
+
+  **************************************************************************/
+
+void
+moveScroller(HDWindow * hdWindow)
+{
+    XWindowChanges wc;
+
+    /** moves the scroller to it's proper place **/
+
+    int t = (int) (hdWindow->fScrollBarHeight * (-hdWindow->page->scroll_off));
+    hdWindow->fScrollerTopPos = (int) (t / hdWindow->page->scrolling->height);
+    wc.x = 0;
+    wc.y = hdWindow->fScrollerTopPos;
+    wc.width = supwidth;
+    wc.height = hdWindow->fScrollerHeight;
+    XConfigureWindow(gXDisplay, hdWindow->scroller,
+                     CWX | CWY | CWHeight | CWWidth,
+                     &wc);
+    drawScroller3DEffects(hdWindow, 0, 0, wc.width, wc.height);
+}
+
+#define tophalf(y) ((y % 2 == 0)?(y/2):(y/2) + 1)
+#define bothalf(y) (y/2)
+
+void
+drawScrollLines(void)
+{
+    /* Checks the page_flags to see if we need a top, or a bottom line.   */
+    /* These are the horizontal lines framing a scrolling region when the */
+    /* scrolling region is not the entire window.                         */
+
+    if (!(gWindow->page->page_flags & NOLINES)) {
+        line_top_group();
+        if (gWindow->page->header->height) {
+            XDrawLine(gXDisplay, gWindow->fMainWindow, gWindow->fStandardGC,
+                      0,
+                      gWindow->page->top_scroll_margin - tophalf(gWindow->border_width)
+                      - 2 * scroll_top_margin,
+                      gWindow->scrollwidth,
+                      gWindow->page->top_scroll_margin - tophalf(gWindow->border_width)
+                      - 2 * scroll_top_margin);
+        }
+        if (gWindow->page->footer->height) {
+            XDrawLine(gXDisplay, gWindow->fMainWindow, gWindow->fStandardGC,
+                      0,
+                      gWindow->page->bot_scroll_margin + bothalf(gWindow->border_width) - 1,
+                      gWindow->scrollwidth,
+                      gWindow->page->bot_scroll_margin + bothalf(gWindow->border_width) - 1);
+        }
+        pop_group_stack();
+    }
+}
+
+
+/*
+ * Calculates all the measures for the scrollbars
+ */
+
+void
+calculateScrollBarMeasures(void)
+{
+    int t;
+
+    /*
+     * The scrollhieght is the height of the scrolling region visible in the
+     * HT window. Notice how it is a multiple of line height. This was needed
+     * to make everything scroll nicely.
+     */
+
+    gWindow->scrollheight = gWindow->page->bot_scroll_margin -
+        gWindow->page->top_scroll_margin - scroll_top_margin;
+    gWindow->scrollheight = gWindow->scrollheight - gWindow->scrollheight % line_height;
+
+    /*
+     * Now do a quick check to see if I really need a scroll bar, and if not,
+     * just return right away
+     */
+
+    if (gWindow->scrollheight >= gWindow->page->scrolling->height) {
+        gWindow->page->scroll_off = 0;
+        return;
+    }
+
+    /*
+     * The height of the scrollbar region, extends form the top page margin
+     * all the way to the bottom, excluding the room needed for the up and
+     * down windows
+     */
+
+    gWindow->fScrollBarHeight = gWindow->page->bot_scroll_margin -
+        gWindow->page->top_scroll_margin - 2 * supheight -
+        2 * gWindow->border_width;
+
+    gWindow->scrollupy = gWindow->page->top_scroll_margin - gWindow->border_width;
+    gWindow->scrollupy -= 2 * scroll_top_margin;
+    gWindow->scrolldowny = gWindow->page->bot_scroll_margin
+        - supheight - gWindow->border_width;
+    gWindow->scrollbary = gWindow->scrollupy + supheight + gWindow->border_width;
+    gWindow->scrollx = gWindow->width - supwidth - gWindow->border_width;
+
+    /*
+     * the scroller height is calculated from the following formula
+     *
+     * fScrollerHeight                    scrollheight --------------       ==
+     * --------- ------------- fScrollBarHeight
+     * page->scrolling_height
+     *
+     */
+
+    gWindow->fScrollerHeight = 1 + 2 * scroll_top_margin +        /** possible integer error correction **/
+        (int) (gWindow->fScrollBarHeight * gWindow->scrollheight / gWindow->page->scrolling->height);
+
+    /*
+     * Check the scroll offset, to see if it is too Large
+     */
+
+    if (-(gWindow->page->scroll_off) >
+        (gWindow->page->scrolling->height - gWindow->scrollheight))
+        gWindow->page->scroll_off =
+            -(gWindow->page->scrolling->height - gWindow->scrollheight);
+
+    /*
+     * Then move the top of the scroller to it's proper position
+     */
+
+    gWindow->fScrollBarHeight += 2 * scroll_top_margin;
+    t = (int) (gWindow->fScrollBarHeight * (-gWindow->page->scroll_off));
+    gWindow->fScrollerTopPos = (int) (t / (gWindow->page->scrolling->height));
+}
+
+void
+linkScrollBars(void)
+{
+    HyperLink *uplink = (HyperLink *) halloc(sizeof(HyperLink), "HyperLink");
+    HyperLink *downlink = (HyperLink *) halloc(sizeof(HyperLink), "HyperLink");
+    HyperLink *barlink = (HyperLink *) halloc(sizeof(HyperLink), "HyperLink");
+
+    uplink->win = gWindow->fScrollUpWindow;
+    downlink->win = gWindow->fScrollDownWindow;
+    barlink->win = gWindow->scrollbar;
+    uplink->type = Scrollupbutton;
+    downlink->type = Scrolldownbutton;
+    barlink->type = Scrollbar;
+    barlink->x = barlink->y = 0;
+    uplink->x = uplink->y = 0;
+    downlink->x = downlink->y = 0;
+    uplink->reference.node = NULL;
+    downlink->reference.node = NULL;
+    hash_insert(gLinkHashTable, (char *)uplink,(char *) &uplink->win);
+    hash_insert(gLinkHashTable, (char *)barlink,(char *) &barlink->win);
+    hash_insert(gLinkHashTable, (char *)downlink,(char *) &downlink->win);
+}
+
+void
+scrollUp(void)
+{
+
+    if (gWindow->page->scroll_off == 0);       /* BeepAtTheUser(); *//* The
+                                                 * beeping annoyed me. RSS */
+    else {
+        changeWindowBackgroundPixmap(gWindow->fScrollUpWindow, sup_pressed);
+
+        gWindow->page->scroll_off += line_height;      /* Scroll a line */
+        if (gWindow->page->scroll_off > 0)
+            gWindow->page->scroll_off = 0;
+        XCopyArea(gXDisplay, gWindow->fScrollWindow, gWindow->fScrollWindow, gWindow->fStandardGC,
+                  0, 0,
+            gWindow->scrollwidth, gWindow->scrollheight - line_height + 1,
+                  0, line_height);
+        XClearArea(gXDisplay, gWindow->fScrollWindow, 0, 0,
+                   gWindow->scrollwidth,
+                   line_height, False);
+        scroll_page(gWindow->page);
+
+        changeWindowBackgroundPixmap(gWindow->fScrollUpWindow, sup);
+    }
+
+}
+
+void
+scrollUpPage(void)
+{
+    if (gWindow->page->scroll_off == 0);       /* BeepAtTheUser(); */
+    else {
+        /* Scroll a page */
+
+        gWindow->page->scroll_off += ch(gWindow->scrollheight) - line_height;
+        if (gWindow->page->scroll_off > 0)
+            gWindow->page->scroll_off = 0;
+
+        XClearWindow(gXDisplay, gWindow->fScrollWindow);
+        scroll_page(gWindow->page);
+    }
+}
+
+void
+scrollToFirstPage(void)
+{
+    if (gWindow->page->scroll_off == 0);       /* BeepAtTheUser(); */
+    else {
+        gWindow->page->scroll_off = 0;
+        XClearWindow(gXDisplay, gWindow->fScrollWindow);
+        scroll_page(gWindow->page);
+    }
+}
+
+void
+scrollDown(void)
+{
+
+    if (-(gWindow->page->scroll_off) >=
+        (gWindow->page->scrolling->height - gWindow->scrollheight)) {
+        ;                       /* BeepAtTheUser(); */
+    }
+    else {
+        changeWindowBackgroundPixmap(gWindow->fScrollDownWindow, sdown_pressed);
+
+        gWindow->page->scroll_off -= line_height;      /* Scroll a line */
+
+        XCopyArea(gXDisplay, gWindow->fScrollWindow, gWindow->fScrollWindow, gWindow->fStandardGC,
+                  0, line_height,
+            gWindow->scrollwidth, gWindow->scrollheight - line_height + 1,
+                  0, 0);
+        XClearArea(gXDisplay, gWindow->fScrollWindow, 0,
+                   gWindow->scrollheight - line_height,
+                   gWindow->scrollwidth,
+                   line_height, False);
+        scroll_page(gWindow->page);
+
+        changeWindowBackgroundPixmap(gWindow->fScrollDownWindow, sdown);
+    }
+}
+
+
+void
+scrollDownPage(void)
+{
+    if (gWindow->page->scrolling == NULL || (-(gWindow->page->scroll_off) >=
+            (gWindow->page->scrolling->height - gWindow->scrollheight))) {
+        ;                       /* BeepAtTheUser(); */
+    }
+    else {
+        gWindow->page->scroll_off -= ch(gWindow->scrollheight) - line_height;
+
+        if (-(gWindow->page->scroll_off) >
+            (gWindow->page->scrolling->height - gWindow->scrollheight))
+            gWindow->page->scroll_off = -
+                (gWindow->page->scrolling->height - gWindow->scrollheight);
+
+        XClearWindow(gXDisplay, gWindow->fScrollWindow);
+
+        scroll_page(gWindow->page);
+    }
+}
+
+void
+scrollScroller(XButtonEvent * event)
+{
+
+    /*
+     * This routine checks to see where in the window the button press
+     * occured. It then tries to move the scroller so that the top of the
+     * scroller is at the spot of the event
+     */
+
+    int y = event->y;
+    int top = y;
+
+    if (top < 0) {
+        top = 0;
+        if (gWindow->fScrollerTopPos == 0)
+            return;
+        gWindow->page->scroll_off = 0;
+    }
+    else if ((top + gWindow->fScrollerHeight) > gWindow->fScrollBarHeight) {
+        top = gWindow->fScrollBarHeight - gWindow->fScrollerHeight;
+        if (top == gWindow->fScrollerTopPos)
+            return;
+        gWindow->page->scroll_off =
+            -(gWindow->page->scrolling->height - gWindow->scrollheight);
+        gWindow->page->scroll_off -= gWindow->page->scroll_off % line_height;
+    }
+    else {                      /** top is in an ok spot **/
+        int t;
+
+        t = -(gWindow->page->scrolling->height) * top;
+        t = t / (gWindow->fScrollBarHeight);
+        if (gWindow->page->scroll_off == (t -= t % line_height))
+            return;
+        gWindow->page->scroll_off = t;
+        gWindow->fScrollerTopPos = top;
+    }
+    XClearWindow(gXDisplay, gWindow->fScrollWindow);
+    scroll_page(gWindow->page);
+}
+
+
+void
+hideScrollBars(HDWindow * hdWindow)
+{
+    XUnmapWindow(gXDisplay, hdWindow->fScrollDownWindow);
+    XUnmapWindow(gXDisplay, hdWindow->fScrollUpWindow);
+    XUnmapWindow(gXDisplay, hdWindow->scrollbar);
+    XUnmapWindow(gXDisplay, hdWindow->scroller);
+}
+
+void
+getScrollBarMinimumSize(int *width, int *height)
+{
+    (*width)  = sup_width + 4;
+    (*height) = sup_height + sdown_height + 5;
+}
+
+static int
+ch(int height)
+{
+    /*int rheight;*/
+    int rem = height % line_height;
+
+    if (rem == 0)
+        return height;
+    return height - rem + line_height;
+}
+
+static void
+changeWindowBackgroundPixmap(Window window, Pixmap pixmap)
+{
+    if (pixmap) {
+        XSetWindowAttributes at;
+
+        at.background_pixmap = pixmap;
+        XChangeWindowAttributes(gXDisplay, window, CWBackPixmap, &at);
+        XClearWindow(gXDisplay, window);
+    }
+}