Commit FS#12321 - Touchscreen: List line padding, to more easily select lines

This adds line padding to lists on touchscreens,
in order to make lists reasonably useful without huge fonts.

It's configurable:
* Automatic (default, line height calculated using a lcd dpi aware function)
* Off (status quo, line height = font height)
* X pixels (from 2 to 50 in even steps)

The automatic setting should/aims to Just Work Out Of The Box on all targets

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30773 a1c6a512-1295-4272-9138-f99709370657

6 files changed, 61 insertions, 23 deletions

diff --git a/apps/gui/bitmap/list.c b/apps/gui/bitmap/list.c
index 69cda9fa85..09a66f3386 100644
--- a/apps/gui/bitmap/list.c
+++ b/apps/gui/bitmap/list.c
@@ -102,13 +102,15 @@ static bool draw_title(struct screen *display, struct gui_synclist *list)
     if (!list_display_title(list, screen))
         return false;
     *title_text_vp = *(list->parent[screen]);
-    title_text_vp->height = font_get(title_text_vp->font)->height;
+    title_text_vp->height = title_text_vp->line_height;
 
     if (list->title_icon != Icon_NOICON && global_settings.show_icons)
     {
         struct viewport title_icon = *title_text_vp;
 
         title_icon.width = get_icon_width(screen) + ICON_PADDING * 2;
+        title_icon.y += (title_icon.height - get_icon_height(screen)) / 2;
+        title_icon.height = get_icon_height(screen);
         if (VP_IS_RTL(&title_icon))
         {
             title_icon.x += title_text_vp->width - title_icon.width;
@@ -120,7 +122,7 @@ static bool draw_title(struct screen *display, struct gui_synclist *list)
         title_text_vp->width -= title_icon.width;
 
         display->set_viewport(&title_icon);
-        screen_put_icon(display, 0, 0, list->title_icon);
+        screen_put_iconxy(display, 0, 0, list->title_icon);
     }
 #ifdef HAVE_LCD_COLOR
     if (list->title_color >= 0)
@@ -136,7 +138,7 @@ static bool draw_title(struct screen *display, struct gui_synclist *list)
 void list_draw(struct screen *display, struct gui_synclist *list)
 {
     struct viewport list_icons;
-    int start, end, line_height, style, i;
+    int start, end, line_height, style, item_offset, i;
     const int screen = display->screen_type;
     const int list_start_item = list->start_item[screen];
     const int icon_width = get_icon_width(screen) + ICON_PADDING;
@@ -147,19 +149,21 @@ void list_draw(struct screen *display, struct gui_synclist *list)
 #ifdef HAVE_LCD_COLOR
     unsigned char cur_line = 0;
 #endif
-    int item_offset;
+    int icon_yoffset = 0; /* to center the icon */
     bool show_title;
     struct viewport *list_text_vp = &list_text[screen];
 
-    line_height = font_get(parent->font)->height;
+    line_height = parent->line_height;
     display->set_viewport(parent);
     display->clear_viewport();
     display->scroll_stop(list_text_vp);
     *list_text_vp = *parent;
+    list_text_vp->line_height = line_height;
     if ((show_title = draw_title(display, list)))
     {
-        list_text_vp->y += line_height;
-        list_text_vp->height -= line_height;
+        int title_height = title_text[screen].height;
+        list_text_vp->y += title_height;
+        list_text_vp->height -= title_height;
     }
 
     const int nb_lines = viewport_get_nb_lines(list_text_vp);
@@ -232,6 +236,7 @@ void list_draw(struct screen *display, struct gui_synclist *list)
             list_icons.x += list_text_vp->width + ICON_PADDING;
         else
             list_text_vp->x += list_icons.width + ICON_PADDING;
+        icon_yoffset = (line_height - get_icon_height(screen)) / 2;
     }
 
     for (i=start; i<end && i<list->nb_items; i++)
@@ -333,14 +338,18 @@ void list_draw(struct screen *display, struct gui_synclist *list)
         display->set_viewport(&list_icons);
         if (list->callback_get_item_icon != NULL)
         {
-            screen_put_icon_with_offset(display, show_cursor?1:0,
-                                    (line),show_cursor?ICON_PADDING:0,draw_offset,
-                                    list->callback_get_item_icon(i, list->data));
+            int xoff = show_cursor ? get_icon_width(screen) + ICON_PADDING : 0;
+            screen_put_iconxy(display, xoff,
+                            line*line_height + draw_offset + icon_yoffset,
+                            list->callback_get_item_icon(i, list->data));
         }
+        /* do the cursor */
         if (show_cursor && i >= list->selected_item &&
                 i <  list->selected_item + list->selected_size)
         {
-            screen_put_icon_with_offset(display, 0, line, 0, draw_offset, Icon_Cursor);
+            screen_put_iconxy(display, 0,
+                            line*line_height + draw_offset + icon_yoffset,
+                            Icon_Cursor);
         }
     }
     display->set_viewport(parent);
@@ -369,8 +378,7 @@ static int scrollbar_scroll(struct gui_synclist * gui_list,
     {
         /* scrollbar scrolling is still line based */
         y_offset = 0;
-        int scrollbar_size = nb_lines*
-            font_get(gui_list->parent[screen]->font)->height;
+        int scrollbar_size = nb_lines*gui_list->parent[screen]->line_height;
         int actual_y = y - list_text[screen].y;
 
         int new_selection = (actual_y * gui_list->nb_items)
@@ -558,7 +566,7 @@ static int kinetic_callback(struct timeout *tmo)
         return 0;
 
     struct cb_data *data = (struct cb_data*)tmo->data;
-    int line_height = font_get(data->list->parent[0]->font)->height;
+    int line_height = data->list->parent[0]->line_height;
     /* ds = v*dt */
     int pixel_diff = data->velocity * RELOAD_INTERVAL / HZ;
     /* remember signedness to detect stopping */
@@ -627,7 +635,7 @@ unsigned gui_synclist_do_touchscreen(struct gui_synclist * gui_list)
     struct viewport *parent = gui_list->parent[screen];
     const int button = action_get_touchscreen_press_in_vp(&x, &y, parent);
     const int list_start_item = gui_list->start_item[screen];
-    const int line_height = font_get(gui_list->parent[screen]->font)->height;
+    const int line_height = gui_list->parent[screen]->line_height;
     const struct viewport *list_text_vp = &list_text[screen];
     const bool old_released = released;
     const bool show_title = list_display_title(gui_list, screen);
diff --git a/apps/gui/icon.c b/apps/gui/icon.c
index 628196a98f..87ea0718fb 100644
--- a/apps/gui/icon.c
+++ b/apps/gui/icon.c
@@ -277,3 +277,8 @@ int get_icon_width(enum screen_type screen_type)
 {
     return ICON_WIDTH(screen_type);
 }
+
+int get_icon_height(enum screen_type screen_type)
+{
+    return ICON_HEIGHT(screen_type);
+}
diff --git a/apps/gui/icon.h b/apps/gui/icon.h
index e79defe798..ca7f04841d 100644
--- a/apps/gui/icon.h
+++ b/apps/gui/icon.h
@@ -109,8 +109,11 @@ void icons_init(void);
 #ifdef HAVE_LCD_CHARCELLS
 # define CURSOR_CHAR 0xe10c
 # define get_icon_width(a) 6
+# define get_icon_height(a) 1 /* needs to be verified */
 #else
 int get_icon_width(enum screen_type screen_type);
+int get_icon_height(enum screen_type screen_type);
 #endif
 
+
 #endif /*_GUI_ICON_H_*/
diff --git a/apps/gui/list.c b/apps/gui/list.c
index 1a90ff9e40..66c3438574 100644
--- a/apps/gui/list.c
+++ b/apps/gui/list.c
@@ -78,6 +78,21 @@ void list_init(void)
     add_event(GUI_EVENT_THEME_CHANGED, false, list_force_reinit);
 }
 
+#ifdef HAVE_TOUCHSCREEN
+static int line_height_from_lcd_dpi(const struct viewport *vp)
+{
+    /* the 4/12 factor is designed for reasonable item size on a 160dpi screen */
+    return MAX(lcd_get_dpi()*4/12, (int)font_get(vp->font)->height);
+}
+
+static int list_line_height(const struct viewport *vp)
+{
+    if (global_settings.list_line_padding == -1)
+        return line_height_from_lcd_dpi(vp);
+    return font_get(vp->font)->height + global_settings.list_line_padding;
+}
+#endif
+
 static void list_init_viewports(struct gui_synclist *list)
 {
     int parent_used;
@@ -90,6 +105,9 @@ static void list_init_viewports(struct gui_synclist *list)
         {
             list->parent[i] = &parent[i];
             viewport_set_defaults(&parent[i], i);
+#ifdef HAVE_TOUCHSCREEN
+            parent[i].line_height = list_line_height(list->parent[i]);
+#endif
 #ifdef HAVE_BUTTONBAR
             if (screens[i].has_buttonbar)
                 list->parent[i]->height -= BUTTONBAR_HEIGHT;
@@ -124,13 +142,15 @@ bool list_display_title(struct gui_synclist *list, enum screen_type screen)
 
 static int list_get_nb_lines(struct gui_synclist *list, enum screen_type screen)
 {
-    struct viewport vp = *list->parent[screen];
-    int skin_count = skinlist_get_line_count(screen, list);
-    if (skin_count >= 0)
-        return skin_count;
-    if (list_display_title(list, screen))
-        vp.height -= font_get(list->parent[screen]->font)->height;
-    return viewport_get_nb_lines(&vp);
+    struct viewport *vp = list->parent[screen];
+    int lines = skinlist_get_line_count(screen, list);
+    if (lines < 0)
+    {
+        lines = viewport_get_nb_lines(vp);
+        if (list_display_title(list, screen))
+            lines -= 1;
+    }
+    return lines;
 }
 #else
 #define list_display_title(l, i) false
diff --git a/apps/gui/viewport.c b/apps/gui/viewport.c
index 2ab6c343ef..c5e44270d4 100644
--- a/apps/gui/viewport.c
+++ b/apps/gui/viewport.c
@@ -223,7 +223,7 @@ static bool is_theme_enabled(enum screen_type screen)
 int viewport_get_nb_lines(const struct viewport *vp)
 {
 #ifdef HAVE_LCD_BITMAP
-    return vp->height/font_get(vp->font)->height;
+    return vp->height/vp->line_height;
 #else
     (void)vp;
     return 2;
@@ -318,6 +318,7 @@ void viewport_set_fullscreen(struct viewport *vp,
     set_default_align_flags(vp);
 #endif
     vp->font = global_status.font_id[screen];
+    vp->line_height = font_get(vp->font)->height;
     vp->drawmode = DRMODE_SOLID;
 #if LCD_DEPTH > 1
 #ifdef HAVE_REMOTE_LCD
diff --git a/apps/gui/viewport.h b/apps/gui/viewport.h
index 51ab35e575..3da001e190 100644
--- a/apps/gui/viewport.h
+++ b/apps/gui/viewport.h
@@ -35,6 +35,7 @@ int viewport_get_nb_lines(const struct viewport *vp);
 #define THEME_UI_VIEWPORT           (BIT_N(1))
 #define THEME_BUTTONBAR             (BIT_N(2))
 #define THEME_LANGUAGE              (BIT_N(3))
+#define THEME_LISTS                 (BIT_N(3))
 #define THEME_ALL                   (~(0u))
 
 #ifndef __PCTOOL__