[Freeciv-Dev] (PR#6272) scroll positions for the mapview

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

This patch introduces "scroll positions" that can be used in scrolling 
and clipping the mapview window.

The main advantage is that it hides the logic of how scrolling works 
behind a set of 3 functions.  Thus changing the scrolling logic can be 
done without any updates to the GUI needed.  This is useful both for 
gen-topologies and when trying to fix iso-view scrolling.

Tested for gui-gtk and gui-xaw only.  Untested support for gui-gtk-2.0 
and gui-win32 is included.

jason

Index: client/mapview_common.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/mapview_common.c,v
retrieving revision 1.60
diff -u -r1.60 mapview_common.c
--- client/mapview_common.c     2003/09/23 16:18:05     1.60
+++ client/mapview_common.c     2003/09/24 20:30:17
@@ -288,19 +288,49 @@
   return normalize_map_pos(map_x, map_y);
 }
 
-/**************************************************************************
-  Return the range of values that the mapview origin can take.  Useful
-  for scrollbars or when manually clipping the window.
-**************************************************************************/
-void get_mapview_clipping_window(int *xmin, int *ymin,
-                                int *xmax, int *ymax,
-                                int *xsize, int *ysize)
+/****************************************************************************
+  Return the range of values that the mapview origin can take, in scroll
+  positins.  Useful for scrollbars or when manually clipping the window.
+****************************************************************************/
+void get_mapview_scroll_window(int *xmin, int *ymin, int *xmax, int *ymax,
+                              int *xsize, int *ysize)
 {
   *xmin = *ymin = 0;
   *xmax = map.xsize;
   *ymax = map.ysize + EXTRA_BOTTOM_ROW;
   *xsize = mapview_canvas.tile_width;
   *ysize = mapview_canvas.tile_height;
+}
+
+/****************************************************************************
+  Find the current scroll position (origin) of the mapview.
+****************************************************************************/
+void get_mapview_scroll_pos(int *scroll_x, int *scroll_y)
+{
+  map_to_native_pos(scroll_x, scroll_y,
+                   mapview_canvas.map_x0, mapview_canvas.map_y0);
+}
+
+/****************************************************************************
+  Set the scroll position (origin) of the mapview, and update the GUI.
+****************************************************************************/
+void set_mapview_scroll_pos(int scroll_x, int scroll_y)
+{
+  int xmin, ymin, xmax, ymax, xsize, ysize, x0, y0;
+
+  get_mapview_scroll_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  native_to_map_pos(&x0, &y0, scroll_x, scroll_y);
+
+  x0 = CLIP(xmin, x0, xmax - xsize);
+  y0 = CLIP(ymin, y0, ymax - ysize);
+
+  if (x0 != mapview_canvas.map_x0 || y0 != mapview_canvas.map_y0) {
+    mapview_canvas.map_x0 = x0;
+    mapview_canvas.map_y0 = y0;
+
+    update_map_canvas_visible();
+    refresh_overview_viewrect();
+  }
 }
 
 /**************************************************************************
Index: client/mapview_common.h
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/mapview_common.h,v
retrieving revision 1.37
diff -u -r1.37 mapview_common.h
--- client/mapview_common.h     2003/07/25 18:59:45     1.37
+++ client/mapview_common.h     2003/09/24 20:30:17
@@ -134,9 +134,11 @@
 bool map_to_canvas_pos(int *canvas_x, int *canvas_y, int map_x, int map_y);
 bool canvas_to_map_pos(int *map_x, int *map_y, int canvas_x, int canvas_y);
 
-void get_mapview_clipping_window(int *xmin, int *ymin,
-                                int *xmax, int *ymax,
-                                int *xsize, int *ysize);
+void get_mapview_scroll_window(int *xmin, int *ymin,
+                              int *xmax, int *ymax,
+                              int *xsize, int *ysize);
+void get_mapview_scroll_pos(int *scroll_x, int *scroll_y);
+void set_mapview_scroll_pos(int scroll_x, int scroll_y);
 
 void get_center_tile_mapcanvas(int *map_x, int *map_y);
 void center_tile_mapcanvas(int map_x, int map_y);
Index: client/gui-gtk/mapview.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/gui-gtk/mapview.c,v
retrieving revision 1.180
diff -u -r1.180 mapview.c
--- client/gui-gtk/mapview.c    2003/08/12 18:54:37     1.180
+++ client/gui-gtk/mapview.c    2003/09/24 20:30:17
@@ -1153,8 +1153,11 @@
 **************************************************************************/
 void update_map_canvas_scrollbars(void)
 {
-  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_hadj), map_view_x0);
-  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_vadj), map_view_y0);
+  int scroll_x, scroll_y;
+
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
+  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_hadj), scroll_x);
+  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_vadj), scroll_y);
 }
 
 /**************************************************************************
@@ -1164,7 +1167,7 @@
 {
   int xmin, ymin, xmax, ymax, xsize, ysize;
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  get_mapview_scroll_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
 
   map_hadj = gtk_adjustment_new(-1, xmin, xmax, 1, xsize, xsize);
   map_vadj = gtk_adjustment_new(-1, ymin, ymax, 1, ysize, ysize);
@@ -1187,28 +1190,21 @@
 **************************************************************************/
 void scrollbar_jump_callback(GtkAdjustment *adj, gpointer hscrollbar)
 {
-  int last_map_view_x0;
-  int last_map_view_y0;
-
-  gfloat percent=adj->value;
+  int scroll_x, scroll_y;
 
   if (!can_client_change_view()) {
     return;
   }
 
-  last_map_view_x0=map_view_x0;
-  last_map_view_y0=map_view_y0;
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
 
-  if(hscrollbar)
-    map_view_x0=percent;
-  else {
-    map_view_y0=percent;
+  if (hscrollbar) {
+    scroll_x = adj->value;
+  } else {
+    scroll_y = adj->value;
   }
 
-  if (last_map_view_x0!=map_view_x0 || last_map_view_y0!=map_view_y0) {
-    update_map_canvas_visible();
-    refresh_overview_viewrect();
-  }
+  set_mapview_scroll_pos(scroll_x, scroll_y);
 }
 
   
Index: client/gui-gtk-2.0/mapview.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/gui-gtk-2.0/mapview.c,v
retrieving revision 1.74
diff -u -r1.74 mapview.c
--- client/gui-gtk-2.0/mapview.c        2003/08/12 18:54:37     1.74
+++ client/gui-gtk-2.0/mapview.c        2003/09/24 20:30:17
@@ -1236,8 +1236,11 @@
 **************************************************************************/
 void update_map_canvas_scrollbars(void)
 {
-  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_hadj), map_view_x0);
-  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_vadj), map_view_y0);
+  int scroll_x, scroll_y;
+
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
+  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_hadj), scroll_x);
+  gtk_adjustment_set_value(GTK_ADJUSTMENT(map_vadj), scroll_y);
 }
 
 /**************************************************************************
@@ -1247,7 +1250,7 @@
 {
   int xmin, ymin, xmax, ymax, xsize, ysize;
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  get_mapview_scroll_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
 
   map_hadj = gtk_adjustment_new(-1, xmin, xmax, 1, xsize, xsize);
   map_vadj = gtk_adjustment_new(-1, ymin, ymax, 1, ysize, ysize);
@@ -1270,28 +1273,21 @@
 **************************************************************************/
 void scrollbar_jump_callback(GtkAdjustment *adj, gpointer hscrollbar)
 {
-  int last_map_view_x0;
-  int last_map_view_y0;
-
-  gfloat percent=adj->value;
+  int scroll_x, scroll_y;
 
   if (!can_client_change_view()) {
     return;
   }
 
-  last_map_view_x0=map_view_x0;
-  last_map_view_y0=map_view_y0;
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
 
-  if(hscrollbar)
-    map_view_x0=percent;
-  else {
-    map_view_y0=percent;
+  if (hscrollbar) {
+    scroll_x = adj->value;
+  } else {
+    scroll_y = adj->value;
   }
 
-  if (last_map_view_x0!=map_view_x0 || last_map_view_y0!=map_view_y0) {
-    update_map_canvas_visible();
-    refresh_overview_viewrect();
-  }
+  set_mapview_scroll_pos(scroll_x, scroll_y);
 }
 
   
Index: client/gui-win32/mapview.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/gui-win32/mapview.c,v
retrieving revision 1.78
diff -u -r1.78 mapview.c
--- client/gui-win32/mapview.c  2003/08/06 16:10:08     1.78
+++ client/gui-win32/mapview.c  2003/09/24 20:30:17
@@ -590,8 +590,7 @@
 {
   int xmin, ymin, xmax, ymax, xsize, ysize;
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
-
+  get_mapview_scroll_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
   ScrollBar_SetRange(map_scroll_h, xmin, xmax, TRUE);
   ScrollBar_SetRange(map_scroll_v, ymin, ymax, TRUE);
 }
@@ -602,8 +601,11 @@
 void
 update_map_canvas_scrollbars(void)
 {
-  ScrollBar_SetPos(map_scroll_h,map_view_x,TRUE);
-  ScrollBar_SetPos(map_scroll_v,map_view_y,TRUE);
+  int scroll_x, scroll_y;
+
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
+  ScrollBar_SetPos(map_scroll_h, scroll_x, TRUE);
+  ScrollBar_SetPos(map_scroll_v, scroll_y, TRUE);
 }
 
 /**************************************************************************
@@ -1010,17 +1012,14 @@
 **************************************************************************/
 void map_handle_hscroll(int pos)
 {
-  int xmin, ymin, xmax, ymax, xsize, ysize;
+  int scroll_x, scroll_y;
 
   if (!can_client_change_view()) {
     return;
   }
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
-  map_view_x = CLIP(xmin, pos, xmax - xsize);
-
-  update_map_canvas_visible();
-  refresh_overview_viewrect();                                                
+  set_mapview_scroll_pos(&scroll_x, &scroll_y);
+  set_mapview_scroll_pos(pos, scroll_y);
 }
 
 /**************************************************************************
@@ -1028,17 +1027,14 @@
 **************************************************************************/
 void map_handle_vscroll(int pos)
 {
-  int xmin, ymin, xmax, ymax, xsize, ysize;
+  int scroll_x, scroll_y;
 
   if (!can_client_change_view()) {
     return;
   }
-
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
-  map_view_y = CLIP(ymin, pos, ymax - ysize);
 
-  update_map_canvas_visible();
-  refresh_overview_viewrect();
+  set_mapview_scroll_pos(&scroll_x, &scroll_y);
+  set_mapview_scroll_pos(scroll_x, pos);
 }
 
 /**************************************************************************
Index: client/gui-xaw/mapview.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/client/gui-xaw/mapview.c,v
retrieving revision 1.147
diff -u -r1.147 mapview.c
--- client/gui-xaw/mapview.c    2003/08/06 07:34:38     1.147
+++ client/gui-xaw/mapview.c    2003/09/24 20:30:18
@@ -744,11 +744,13 @@
 {
   float shown_h, top_h, shown_v, top_v;
   int xmin, ymin, xmax, ymax, xsize, ysize;
+  int scroll_x, scroll_y;
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  get_mapview_scroll_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
 
-  top_h = (float)(map_view_x0 - xmin) / (float)(xmax - xmin);
-  top_v = (float)(map_view_y0 - ymin) / (float)(ymax - ymin);
+  top_h = (float)(scroll_x - xmin) / (float)(xmax - xmin);
+  top_v = (float)(scroll_y - ymin) / (float)(ymax - ymin);
 
   shown_h = (float)xsize / (float)(xmax - xmin);
   shown_v = (float)ysize / (float)(ymax - ymin);
@@ -1027,25 +1029,22 @@
 {
   float percent=*(float*)percent_ptr;
   int xmin, ymin, xmax, ymax, xsize, ysize;
+  int scroll_x, scroll_y;
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
-
   if (!can_client_change_view()) {
     return;
   }
 
+  get_mapview_scroll_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
+
   if(w==map_horizontal_scrollbar) {
-    map_view_x0 = xmin + (percent * (xmax - xmin));
-    map_view_x0 = CLIP(xmin, map_view_x0, xmax - xsize);
+    scroll_x = xmin + (percent * (xmax - xmin));
   } else {
-    map_view_y0 = ymin + (percent * (ymax - ymin));
-    map_view_y0 = CLIP(ymin, map_view_y0, ymax - ysize);
+    scroll_y = ymin + (percent * (ymax - ymin));
   }
 
-  update_map_canvas_visible();
-  /* The scrollbar tracks by itself, while calling the jumpProc,
-     so there's no need to call update_map_canvas_scrollbars() here. */
-  refresh_overview_viewrect();
+  set_mapview_scroll_pos(scroll_x, scroll_y);
 }
 
 
@@ -1056,9 +1055,9 @@
                             XtPointer position_val)
 {
   int position = XTPOINTER_TO_INT(position_val);
-  int xmin, ymin, xmax, ymax, xsize, ysize;
+  int scroll_x, scroll_y;
 
-  get_mapview_clipping_window(&xmin, &ymin, &xmax, &ymax, &xsize, &ysize);
+  get_mapview_scroll_pos(&scroll_x, &scroll_y);
 
   if (!can_client_change_view()) {
     return;
@@ -1066,24 +1065,21 @@
 
   if(w==map_horizontal_scrollbar) {
     if (position > 0) {
-      map_view_x0++;
+      scroll_x++;
     } else {
-      map_view_x0--;
+      scroll_x--;
     }
-    map_view_x0 = CLIP(xmin, map_view_x0, xmax - xsize);
   }
   else {
     if (position > 0) {
-      map_view_y0++;
+      scroll_y++;
     } else {
-      map_view_y0--;
+      scroll_y--;
     }
-    map_view_y0 = CLIP(ymin, map_view_y0, ymax - ysize);
   }
 
-  update_map_canvas_visible();
+  set_mapview_scroll_pos(scroll_x, scroll_y);
   update_map_canvas_scrollbars();
-  refresh_overview_viewrect();
 }
 
 /**************************************************************************