rulers: (Merge from GIMP) Set range in ruler units, not in px

(bzr r12002)

3 files changed, 20 insertions, 33 deletions

diff --git a/src/widgets/desktop-widget.cpp b/src/widgets/desktop-widget.cpp
index 8f7b6445c..a22786b2a 100644
--- a/src/widgets/desktop-widget.cpp
+++ b/src/widgets/desktop-widget.cpp
@@ -1696,23 +1696,17 @@ SPDesktopWidget::viewSetPosition (Geom::Point p)
 void
 sp_desktop_widget_update_rulers (SPDesktopWidget *dtw)
 {
-    /* The viewbox (in integers) must exactly match the size of SPCanvasbuf's pixel buffer.
-     * This is important because the former is being used for drawing the ruler, whereas
-     * the latter is used for drawing e.g. the grids and guides. Only when the viewbox
-     * coincides with the pixel buffer, everything will line up nicely.
-     */
-    Geom::IntRect viewbox = dtw->canvas->getViewboxIntegers();
+    Geom::Rect viewbox = dtw->desktop->get_display_area();
 
-    double const scale = dtw->desktop->current_zoom();
-    double lower_x = viewbox.min()[Geom::X] / scale - dtw->ruler_origin[Geom::X];
-    double upper_x = viewbox.max()[Geom::X] / scale - dtw->ruler_origin[Geom::X];
+    double lower_x = dtw->dt2r * (viewbox.left()  - dtw->ruler_origin[Geom::X]);
+    double upper_x = dtw->dt2r * (viewbox.right() - dtw->ruler_origin[Geom::X]);
     sp_ruler_set_range(SP_RULER(dtw->hruler),
 	      	       lower_x,
 		       upper_x,
 		       (upper_x - lower_x));
 
-    double lower_y = viewbox.min()[Geom::Y] / -scale - dtw->ruler_origin[Geom::Y];
-    double upper_y = viewbox.max()[Geom::Y] / -scale - dtw->ruler_origin[Geom::Y];
+    double lower_y = dtw->dt2r * (viewbox.bottom() - dtw->ruler_origin[Geom::Y]);
+    double upper_y = dtw->dt2r * (viewbox.top()    - dtw->ruler_origin[Geom::Y]);
     sp_ruler_set_range(SP_RULER(dtw->vruler),
                        lower_y,
 		       upper_y,
diff --git a/src/widgets/ruler.cpp b/src/widgets/ruler.cpp
index 733de2239..34d8f1bc5 100644
--- a/src/widgets/ruler.cpp
+++ b/src/widgets/ruler.cpp
@@ -88,15 +88,15 @@ typedef struct
 /// Ruler metrics.
 static SPRulerMetric const sp_ruler_metrics[] = {
   // NOTE: the order of records in this struct must correspond to the SPMetric enum.
-  {1,         { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_NONE
-  {PX_PER_MM, { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_MM
-  {PX_PER_CM, { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_CM
-  {PX_PER_IN, { 1, 2, 4,  8, 16, 32,  64, 128, 256,  512 }, { 1, 2,  4,  8,  16 }}, // SP_IN
-  {PX_PER_FT, { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_FT
-  {PX_PER_PT, { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_PT
-  {PX_PER_PC, { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_PC
-  {PX_PER_PX, { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_PX
-  {PX_PER_M,  { 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_M
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_NONE
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_MM
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_CM
+  {{ 1, 2, 4,  8, 16, 32,  64, 128, 256,  512 }, { 1, 2,  4,  8,  16 }}, // SP_IN
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_FT
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_PT
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_PC
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_PX
+  {{ 1, 2, 5, 10, 25, 50, 100, 250, 500, 1000 }, { 1, 5, 10, 50, 100 }}, // SP_M
 };
 
 
@@ -1252,11 +1252,6 @@ sp_ruler_draw_ticks (SPRuler *ruler)
 
     sp_ruler_get_range (ruler, &lower, &upper, &max_size);
 
-    upper /= priv->metric->pixels_per_unit; // upper and lower are expressed in ruler units
-    lower /= priv->metric->pixels_per_unit;
-    /* "pixels_per_unit" should be "points_per_unit". This is the size of the unit
-    * in 1/72nd's of an inch and has nothing to do with screen pixels */
-
     if ((upper - lower) == 0)
         goto out;
 
@@ -1272,7 +1267,7 @@ sp_ruler_draw_ticks (SPRuler *ruler)
     *    actually measuring the text width, so that the result for the
     *    scale looks consistent with an accompanying vruler
     */
-    scale = (gint)(ceil(priv->max_size / priv->metric->pixels_per_unit));
+    scale = ceil (priv->max_size);
     sprintf (unit_str, "%d", scale);
     text_size = strlen (unit_str) * digit_height + 1;
 
diff --git a/src/widgets/ruler.h b/src/widgets/ruler.h
index c21cf0fa8..7fa3d334c 100644
--- a/src/widgets/ruler.h
+++ b/src/widgets/ruler.h
@@ -18,6 +18,8 @@
 #include <iostream>
 #include <glib.h>
 
+G_BEGIN_DECLS
+
 #define SP_TYPE_RULER            (sp_ruler_get_type ())
 #define SP_RULER(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), SP_TYPE_RULER, SPRuler))
 #define SP_RULER_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass), SP_TYPE_RULER, SPRulerClass))
@@ -30,12 +32,9 @@ typedef struct _SPRuler         SPRuler;
 typedef struct _SPRulerClass    SPRulerClass;
 typedef struct _SPRulerMetric   SPRulerMetric;
 
-/* All distances below are in 1/72nd's of an inch. (According to
- * Adobe that's a point, but points are really 1/72.27 in.)
- */
 struct _SPRuler
 {
-  GtkWidget widget;
+  GtkWidget parent_instance;
 };
 
 struct _SPRulerClass
@@ -45,9 +44,6 @@ struct _SPRulerClass
 
 struct _SPRulerMetric
 {
-  /* This should be points_per_unit. This is the size of the unit
-   * in 1/72nd's of an inch and has nothing to do with screen pixels */
-  gdouble pixels_per_unit;
   gdouble ruler_scale[10];
   gint subdivide[5];        /* five possible modes of subdivision */
 };
@@ -77,6 +73,8 @@ void            sp_ruler_set_metric          (SPRuler        *ruler,
                                               SPMetric        metric);
 SPMetric        sp_ruler_get_metric          (SPRuler        *ruler);
 
+G_END_DECLS
+
 #endif /* __SP_RULER_H__ */
 
 /*