#219: Implement continious scroll

config/config.def.c

@@ -149,4 +149,5 @@ Settings config = {
     .dpi               =                                        -1,
     .threads           =                                         1,
     .scrollbar_width   =                                         8,
+    .scroll_method     =                                         0,
 };

doc/rofi-manpage.markdown

@@ -229,6 +229,9 @@ Filter the list by setting text in input bar to *filter*
 
 Load alternative configuration file.
 
+`-scroll-method` *method*
+
+Select the scrolling method. 0: Per page, 1: continuous.
 
 ### Theming
 

doc/rofi.1

@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "ROFI\-MANPAGE" "" "January 2016" "" ""
+.TH "ROFI\-MANPAGE" "" "February 2016" "" ""
 .
 .SH "NAME"
 \fBrofi\fR \- A window switcher, run launcher, ssh dialog and dmenu replacement
@@ -325,6 +325,12 @@ Filter the list by setting text in input bar to \fIfilter\fR
 .P
 Load alternative configuration file\.
 .
+.P
+\fB\-scroll\-method\fR \fImethod\fR
+.
+.P
+Select the scrolling method\. 0: Per page, 1: continuous\.
+.
 .SS "Theming"
 All colors are either hex #rrggbb values or X11 color names\. \fB\-bg\fR
 .

doc/test_xr.txt

@@ -118,6 +118,8 @@ rofi.dpi:                            101
 rofi.threads:                        8
 ! Scrollbar width
 rofi.scrollbar-width:                8
+! Scrolling method. (0: Page, 1: Centered)
+rofi.scroll-method:                  0
 ! Pidfile location
 rofi.pid:                            /tmp/1000-runtime-dir/rofi.pid
 ! Keybinding

include/settings.h

@@ -149,6 +149,7 @@ typedef struct _Settings
     /** Number threads (1 to disable) */
     unsigned int   threads;
     unsigned int   scrollbar_width;
+    unsigned int   scroll_method;
 } Settings;
 /** Global Settings structure. */
 extern Settings config;

source/view.c

@@ -664,9 +664,10 @@ inline static void rofi_view_nav_last ( RofiViewState * state )
     state->update   = TRUE;
 }
 
-static void rofi_view_draw ( RofiViewState *state, cairo_t *d )
+static unsigned int rofi_scroll_per_page ( RofiViewState * state )
 {
-    unsigned int i, offset = 0;
+    int offset = 0;
+
     // selected row is always visible.
     // If selected is visible do not scroll.
     if ( ( ( state->selected - ( state->last_offset ) ) < ( state->max_elements ) ) && ( state->selected >= ( state->last_offset ) ) ) {
@@ -684,6 +685,35 @@ static void rofi_view_draw ( RofiViewState *state, cairo_t *d )
         // Set the position
         scrollbar_set_handle ( state->scrollbar, page * state->max_elements );
     }
+    return offset;
+}
+
+static unsigned int rofi_scroll_continious ( RofiViewState * state )
+{
+    unsigned int middle = state->menu_lines / 2;
+    unsigned int offset = 0;
+    if ( state->selected > middle ) {
+        if ( state->selected < ( state->filtered_lines - middle ) ) {
+            offset = state->selected - middle;
+        }
+        else {
+            offset = state->filtered_lines - state->menu_lines;
+        }
+    }
+    state->rchanged = TRUE;
+    scrollbar_set_handle ( state->scrollbar, offset );
+    return offset;
+}
+
+static void rofi_view_draw ( RofiViewState *state, cairo_t *d )
+{
+    unsigned int i, offset = 0;
+    if ( config.scroll_method == 1 ) {
+        offset = rofi_scroll_continious ( state );
+    }
+    else {
+        offset = rofi_scroll_per_page ( state );
+    }
     // Re calculate the boxes and sizes, see if we can move this in the menu_calc*rowscolumns
     // Get number of remaining lines to display.
     unsigned int a_lines = MIN ( ( state->filtered_lines - offset ), state->max_elements );
@@ -907,6 +937,7 @@ static void rofi_view_resize ( RofiViewState *state )
             }
         }
         state->max_rows     = MAX ( 1, ( h / element_height ) );
+        state->menu_lines   = state->max_rows;
         state->max_elements = state->max_rows * config.menu_columns;
         // Free boxes no longer needed.
         for ( unsigned int i = state->max_elements; i < last_length; i++ ) {

source/xrmoptions.c

@@ -138,7 +138,8 @@ static XrmOption xrmOptions[] = {
     { xrm_Boolean, "fake-transparency",    { .num  = &config.fake_transparency  }, NULL, "Fake transparency"                           },
     { xrm_SNumber, "dpi",                  { .snum = &config.dpi                }, NULL, "DPI"                                         },
     { xrm_Number,  "threads",              { .num  = &config.threads            }, NULL, "Threads to use for string matching"          },
-    { xrm_Number,  "scrollbar-width",      { .num  = &config.scrollbar_width    }, NULL, "Scrollbar width"                             }
+    { xrm_Number,  "scrollbar-width",      { .num  = &config.scrollbar_width    }, NULL, "Scrollbar width"                             },
+    { xrm_Number,  "scroll-method",        { .num  = &config.scroll_method      }, NULL, "Scrolling method. (0: Page, 1: Centered)"    }
 };
 
 // Dynamic options.