new utility function which takes GimpZoomType and zooms "scalesrc" and

2003-05-05  Michael Natterer  <mitch@gimp.org>

	* app/display/gimpdisplayshell-scale.[ch]
	(gimp_display_shell_scale_zoom_fraction): new utility function
	which takes GimpZoomType and zooms "scalesrc" and "scaledest".
	(gimp_display_shell_scale_calc_fraction): new utility function
	which takes an exact double scale factor and calculates "scalesrc"
	and "scaledest".

	(gimp_display_shell_scale): use the first.
	(gimp_display_shell_scale_fit): use the second.

	* app/tools/gimpmagnifytool.[ch]: use the first to click-zoom and
	the second to area-zoom. Fixes bug #112115. Removed zoom_in() and
	zoom_out() utiliy functions. Removed "GimpZoomType op" from the
	GimpMagnifyTool struct. Cleanup.

ChangeLog

@@ -1,3 +1,20 @@
+2003-05-05  Michael Natterer  <mitch@gimp.org>
+
+	* app/display/gimpdisplayshell-scale.[ch]
+	(gimp_display_shell_scale_zoom_fraction): new utility function
+	which takes GimpZoomType and zooms "scalesrc" and "scaledest".
+	(gimp_display_shell_scale_calc_fraction): new utility function
+	which takes an exact double scale factor and calculates "scalesrc"
+	and "scaledest".
+
+	(gimp_display_shell_scale): use the first.
+	(gimp_display_shell_scale_fit): use the second.
+
+	* app/tools/gimpmagnifytool.[ch]: use the first to click-zoom and
+	the second to area-zoom. Fixes bug #112115. Removed zoom_in() and
+	zoom_out() utiliy functions. Removed "GimpZoomType op" from the
+	GimpMagnifyTool struct. Cleanup.
+
 2003-05-05  Michael Natterer  <mitch@gimp.org>
 
 	* app/display/gimpdisplayshell.c (gimp_display_shell_snap_coords):

app/display/gimpdisplayshell-scale.c

@@ -62,6 +62,112 @@ static gdouble  img2real                           (GimpDisplayShell *shell,
 
 /*  public functions  */
 
+void
+gimp_display_shell_scale_zoom_fraction (GimpZoomType  zoom_type,
+                                        gint         *scalesrc,
+                                        gint         *scaledest)
+{
+  gint src, dest;
+
+  g_return_if_fail (scalesrc != NULL);
+  g_return_if_fail (scaledest != NULL);
+
+  src  = *scalesrc;
+  dest = *scaledest;
+
+  switch (zoom_type)
+    {
+    case GIMP_ZOOM_IN:
+      if (src > 1)
+        src--;
+      else if (dest < 0xFF)
+        dest++;
+      break;
+
+    case GIMP_ZOOM_OUT:
+      if (dest > 1)
+        dest--;
+      else if (src < 0xFF)
+        src++;
+      break;
+
+    default:
+      src  = CLAMP (zoom_type % 100, 1, 0xFF);
+      dest = CLAMP (zoom_type / 100, 1, 0xFF);
+      break;
+    }
+
+  *scalesrc  = src;
+  *scaledest = dest;
+}
+
+void
+gimp_display_shell_scale_calc_fraction (gdouble  zoom_factor,
+                                        gint    *scalesrc,
+                                        gint    *scaledest)
+{
+  gdouble zoom_delta;
+  gdouble min_zoom_delta = G_MAXFLOAT;
+  gint    best_i         = 0xFF;
+  gint    i;
+
+  g_return_if_fail (scalesrc != NULL);
+  g_return_if_fail (scaledest != NULL);
+
+  if (zoom_factor < 1.0)
+    {
+      for (i = 0xFF; i > 0; i--)
+        {
+          *scalesrc  = i;
+          *scaledest = floor ((gdouble) *scalesrc * zoom_factor);
+
+          if (*scaledest < 0x1)
+            *scaledest = 0x1;
+
+          zoom_delta = ABS ((gdouble) *scaledest / (gdouble) *scalesrc -
+                            zoom_factor);
+
+          if (zoom_delta <= min_zoom_delta)
+            {
+              min_zoom_delta = zoom_delta;
+              best_i = i;
+            }
+        }
+
+      *scalesrc  = best_i;
+      *scaledest = floor ((gdouble) *scalesrc * zoom_factor);
+
+      if (*scaledest < 0x1)
+        *scaledest = 0x1;
+    }
+  else
+    {
+      for (i = 0xFF; i > 0; i--)
+        {
+          *scaledest = i;
+          *scalesrc  = ceil ((gdouble) *scaledest / zoom_factor);
+
+          if (*scalesrc < 0x1)
+            *scalesrc = 0x1;
+
+          zoom_delta = ABS ((gdouble) *scaledest / (gdouble) *scalesrc -
+                            zoom_factor);
+
+          if (zoom_delta <= min_zoom_delta)
+            {
+              min_zoom_delta = zoom_delta;
+              best_i = i;
+            }
+        }
+
+      *scaledest = best_i;
+      *scalesrc  = ceil ((gdouble) *scaledest / zoom_factor);
+
+      if (*scalesrc < 0x1)
+        *scalesrc = 0x1;
+    }
+}
+
 void
 gimp_display_shell_scale_setup (GimpDisplayShell *shell)
 {
@@ -204,9 +310,8 @@ gimp_display_shell_scale (GimpDisplayShell *shell,
                           GimpZoomType      zoom_type)
 {
   GimpDisplayConfig *config;
-
+  gint               scalesrc, scaledest;
-  guchar  scalesrc, scaledest;
+  gdouble            offset_x, offset_y;
-  gdouble offset_x, offset_y;
 
   g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell));
 
@@ -220,40 +325,13 @@ gimp_display_shell_scale (GimpDisplayShell *shell,
   offset_x *= ((gdouble) scalesrc / (gdouble) scaledest);
   offset_y *= ((gdouble) scalesrc / (gdouble) scaledest);
 
-  switch (zoom_type)
+  gimp_display_shell_scale_zoom_fraction (zoom_type, &scalesrc, &scaledest);
-    {
-    case GIMP_ZOOM_IN:
-      if (scalesrc > 1)
-	scalesrc--;
-      else
-	if (scaledest < 0xFF)
-	  scaledest++;
-	else
-	  return;
-      break;
 
-    case GIMP_ZOOM_OUT:
-      if (scaledest > 1)
-	scaledest--;
-      else
-	if (scalesrc < 0xFF)
-	  scalesrc++;
-	else
-	  return;
-      break;
-
-    default:
-      scalesrc  = CLAMP (zoom_type % 100, 1, 0xFF);
-      scaledest = CLAMP (zoom_type / 100, 1, 0xFF);
-      break;
-    }
-
-  /*  set the offsets  */
   offset_x *= ((gdouble) scaledest / (gdouble) scalesrc);
   offset_y *= ((gdouble) scaledest / (gdouble) scalesrc);
-  
+
   config = GIMP_DISPLAY_CONFIG (shell->gdisp->gimage->gimp->config);
-      
+
   gimp_display_shell_scale_by_values (shell,
                                       (scaledest << 8) + scalesrc,
                                       (offset_x - (shell->disp_width  / 2)),
@@ -270,12 +348,8 @@ gimp_display_shell_scale_fit (GimpDisplayShell *shell)
   gdouble    zoom_x;
   gdouble    zoom_y;
   gdouble    zoom_factor;
-  gdouble    zoom_delta;
+  gint       scalesrc;
-  gdouble    min_zoom_delta = G_MAXFLOAT;
+  gint       scaledest;
-  gint       scalesrc       = 1;
-  gint       scaledest      = 1;
-  gint       i;
-  gint       best_i         = 0xFF;
 
   g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell));
 
@@ -298,74 +372,12 @@ gimp_display_shell_scale_fit (GimpDisplayShell *shell)
   zoom_y = (gdouble) shell->disp_height / (gdouble) image_height;
 
   if ((gdouble) image_height * zoom_x <= (gdouble) shell->disp_height)
-    {
+    zoom_factor = zoom_x;
-      zoom_factor = zoom_x;
-    }
   else
-    {
+    zoom_factor = zoom_y;
-      zoom_factor = zoom_y;
-    }
 
-  if (zoom_factor < 1.0)
+  gimp_display_shell_scale_calc_fraction (zoom_factor,
-    {
+                                          &scalesrc, &scaledest);
-      for (i = 0xFF; i > 0; i--)
-        {
-          scalesrc  = i;
-          scaledest = floor ((gdouble) scalesrc * zoom_factor);
-
-          if (scaledest < 0x1)
-            {
-              scaledest = 0x1;
-            }
-
-          zoom_delta = ABS ((gdouble) scaledest / (gdouble) scalesrc -
-                            zoom_factor);
-
-          if (zoom_delta <= min_zoom_delta)
-            {
-              min_zoom_delta = zoom_delta;
-              best_i = i;
-            }
-        }
-
-      scalesrc  = best_i;
-      scaledest = floor ((gdouble) scalesrc * zoom_factor);
-
-      if (scaledest < 0x1)
-        {
-          scaledest = 0x1;
-        }
-    }
-  else
-    {
-      for (i = 0xFF; i > 0; i--)
-        {
-          scaledest = i;
-          scalesrc  = ceil ((gdouble) scaledest / zoom_factor);
-
-          if (scalesrc < 0x1)
-            {
-              scalesrc = 0x1;
-            }
-
-          zoom_delta = ABS ((gdouble) scaledest / (gdouble) scalesrc -
-                            zoom_factor);
-
-          if (zoom_delta <= min_zoom_delta)
-            {
-              min_zoom_delta = zoom_delta;
-              best_i = i;
-            }
-        }
-
-      scaledest = best_i;
-      scalesrc  = ceil ((gdouble) scaledest / zoom_factor);
-
-      if (scalesrc < 0x1)
-        {
-          scalesrc = 0x1;
-        }
-    }
 
   gimp_display_shell_scale_by_values (shell,
                                       (scaledest << 8) + scalesrc,

app/display/gimpdisplayshell-scale.h

@@ -20,6 +20,13 @@
 #define __GIMP_DISPLAY_SHELL_SCALE_H__
 
 
+void   gimp_display_shell_scale_zoom_fraction   (GimpZoomType      zoom_type,
+                                                 gint             *scalesrc,
+                                                 gint             *scaledest);
+void   gimp_display_shell_scale_calc_fraction   (gdouble           zoom_factor,
+                                                 gint             *scalesrc,
+                                                 gint             *scaledest);
+
 void   gimp_display_shell_scale_setup           (GimpDisplayShell *shell);
 
 void   gimp_display_shell_scale_set_dot_for_dot (GimpDisplayShell *gdisp,

app/tools/gimpmagnifytool.c

@@ -77,13 +77,6 @@ static void   gimp_magnify_tool_cursor_update   (GimpTool        *tool,
 
 static void   gimp_magnify_tool_draw            (GimpDrawTool    *draw_tool);
 
-static void   zoom_in                           (gint            *src,
-                                                 gint            *dest,
-                                                 gint             scale);
-static void   zoom_out                          (gint            *src,
-                                                 gint            *dest,
-                                                 gint             scale);
-
 
 static GimpDrawToolClass *parent_class = NULL;
 
@@ -220,11 +213,6 @@ gimp_magnify_tool_button_release (GimpTool        *tool,
   GimpMagnifyTool    *magnify;
   GimpMagnifyOptions *options;
   GimpDisplayShell   *shell;
-  gint                win_width, win_height;
-  gint                width, height;
-  gint                scalesrc, scaledest;
-  gint                scale;
-  gint                x1, y1, x2, y2, w, h;
 
   magnify = GIMP_MAGNIFY_TOOL (tool);
   options = GIMP_MAGNIFY_OPTIONS (tool->tool_info->tool_options);
@@ -238,8 +226,13 @@ gimp_magnify_tool_button_release (GimpTool        *tool,
   /*  First take care of the case where the user "cancels" the action  */
   if (! (state & GDK_BUTTON3_MASK))
     {
-      x1 = (magnify->w < 0) ? magnify->x + magnify->w : magnify->x;
+      gint x1, y1, x2, y2, w, h;
-      y1 = (magnify->h < 0) ? magnify->y + magnify->h : magnify->y;
+      gint scalesrc, scaledest;
+      gint win_width, win_height;
+      gint offset_x, offset_y;
+
+      x1 = (magnify->w < 0) ?  magnify->x + magnify->w : magnify->x;
+      y1 = (magnify->h < 0) ?  magnify->y + magnify->h : magnify->y;
       w  = (magnify->w < 0) ? -magnify->w : magnify->w;
       h  = (magnify->h < 0) ? -magnify->h : magnify->h;
       x2 = x1 + w;
@@ -253,34 +246,47 @@ gimp_magnify_tool_button_release (GimpTool        *tool,
 
       win_width  = shell->disp_width;
       win_height = shell->disp_height;
-      width  = (win_width  * scalesrc) / scaledest;
-      height = (win_height * scalesrc) / scaledest;
 
       /* we need to compute the mouse movement in screen coordinates */
-      if ( (SCALEX (shell, w) < options->threshold) || 
+      if ((SCALEX (shell, w) < options->threshold) || 
-           (SCALEY (shell, h) < options->threshold) )
+          (SCALEY (shell, h) < options->threshold))
-	scale = 1;
+        {
+          gimp_display_shell_scale_zoom_fraction (options->zoom_type,
+                                                  &scalesrc, &scaledest);
+        }
       else
-	scale = MIN ((width / w), (height / h));
+        {
+          gint    width, height;
+          gdouble scale;
 
-      magnify->op = options->zoom_type;
+          width  = UNSCALEX (shell, win_width);
+          height = UNSCALEY (shell, win_height);
 
-      switch (magnify->op)
+          switch (options->zoom_type)
-	{
+            {
-	case GIMP_ZOOM_IN:
+            case GIMP_ZOOM_IN:
-	  zoom_in (&scalesrc, &scaledest, scale);
+              scale = MIN (((gdouble) width  / (gdouble) w),
-	  break;
+                           ((gdouble) height / (gdouble) h));
-	case GIMP_ZOOM_OUT:
+              break;
-	  zoom_out (&scalesrc, &scaledest, scale);
+
-	  break;
+            case GIMP_ZOOM_OUT:
-	}
+              scale = MIN (((gdouble) w / (gdouble) width),
+                           ((gdouble) h / (gdouble) height));
+              break;
+            }
+
+          scale = scale * (gdouble) scaledest / (gdouble) scalesrc;
+
+          gimp_display_shell_scale_calc_fraction (scale,
+                                                  &scalesrc, &scaledest);
+        }
+
+      offset_x = (scaledest * ((x1 + x2) / 2)) / scalesrc - (win_width  / 2);
+      offset_y = (scaledest * ((y1 + y2) / 2)) / scalesrc - (win_height / 2);
 
       gimp_display_shell_scale_by_values (shell,
                                           (scaledest << 8) + scalesrc,
-                                          ((scaledest * ((x1 + x2) / 2)) / scalesrc -
+                                          offset_x, offset_y,
-                                           (win_width / 2)),
-                                          ((scaledest * ((y1 + y2) / 2)) / scalesrc -
-                                           (win_height / 2)),
                                           options->allow_resize);
     }
 }
@@ -369,37 +375,3 @@ gimp_magnify_tool_draw (GimpDrawTool *draw_tool)
                                  magnify->h,
                                  FALSE);
 }
-
-
-/*  magnify utility functions  */
-
-static void
-zoom_in (gint *src,
-	 gint *dest,
-	 gint  scale)
-{
-  while (scale--)
-    {
-      if (*src > 1)
-	(*src)--;
-      else
-	if (*dest < 0x10)
-	  (*dest)++;
-    }
-}
-
-
-static void
-zoom_out (gint *src,
-	  gint *dest,
-	  gint  scale)
-{
-  while (scale--)
-    {
-      if (*dest > 1)
-	(*dest)--;
-      else
-	if (*src < 0x10)
-	  (*src)++;
-    }
-}

app/tools/gimpmagnifytool.h

@@ -38,10 +38,8 @@ struct _GimpMagnifyTool
 {
   GimpDrawTool  parent_instance;
 
-  gint          x, y;       /*  upper left hand coordinate  */
+  gint          x, y;  /*  upper left hand coordinate  */
-  gint          w, h;       /*  width and height            */
+  gint          w, h;  /*  width and height            */
-
-  GimpZoomType  op;         /*  magnify operation           */
 };
 
 struct _GimpMagnifyToolClass