Change grids to use 'user units'. Grids using absolute units are read in but

may be scaled incorrectly due to change of 90 to 96 dpi.

(bzr r13795)

4 files changed, 166 insertions, 68 deletions

diff --git a/src/display/canvas-axonomgrid.cpp b/src/display/canvas-axonomgrid.cpp
index 592c962a6..b81400266 100644
--- a/src/display/canvas-axonomgrid.cpp
+++ b/src/display/canvas-axonomgrid.cpp
@@ -46,6 +46,7 @@
 #include "preferences.h"
 #include "sp-namedview.h"
 #include "sp-object.h"
+#include "sp-root.h"
 #include "svg/svg-color.h"
 #include "2geom/line.h"
 #include "2geom/angle.h"
@@ -213,22 +214,53 @@ static gboolean sp_nv_read_opacity(gchar const *str, guint32 *color)
 void
 CanvasAxonomGrid::readRepr()
 {
+    SPRoot *root = doc->getRoot();
+    double scale_x = 1.0;
+    double scale_y = 1.0;
+    if( root->viewBox_set ) {
+        scale_x = root->width.computed  / root->viewBox.width();
+        scale_y = root->height.computed / root->viewBox.height();
+    }
+
     gchar const *value;
+
     if ( (value = repr->attribute("originx")) ) {
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        origin[Geom::X] = q.value("px");
+
+        if( q.unit->type == UNIT_TYPE_LINEAR ) {
+            // Legacy grid not in 'user units'
+            origin[Geom::X] = q.value("px");
+        } else {
+            // Grid in 'user units'
+            origin[Geom::X] = q.quantity * scale_x;
+        }
     }
+
     if ( (value = repr->attribute("originy")) ) {
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        origin[Geom::Y] = q.value("px");
+
+        if( q.unit->type == UNIT_TYPE_LINEAR ) {
+            // Legacy grid not in 'user units'
+            origin[Geom::Y] = q.value("px");
+        } else {
+            // Grid in 'user units'
+            origin[Geom::Y] = q.quantity * scale_y;
+        }
     }
 
     if ( (value = repr->attribute("spacingy")) ) {
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        lengthy = q.value("px");
+
+        if( q.unit->type == UNIT_TYPE_LINEAR ) {
+            // Legacy grid not in 'user units'
+            lengthy = q.value("px");
+        } else {
+            // Grid in 'user units'
+            lengthy = q.quantity * scale_y; // We do not handle scale_x != scale_y
+        }
         if (lengthy < 0.0500) lengthy = 0.0500;
     }
 
@@ -281,6 +313,10 @@ CanvasAxonomGrid::readRepr()
         snapper->setSnapVisibleOnly(strcmp(value,"false") != 0 && strcmp(value, "0") != 0);
     }
 
+    if ( (value = repr->attribute("units")) ) {
+        gridunit = unit_table.getUnit(value); // Display unit identifier in grid menu
+    }
+
     for (GSList *l = canvasitems; l != NULL; l = l->next) {
         sp_canvas_item_request_update ( SP_CANVAS_ITEM(l->data) );
     }
@@ -316,11 +352,14 @@ _wr.setUpdating (true);
     Inkscape::UI::Widget::RegisteredUnitMenu *_rumg = Gtk::manage( new Inkscape::UI::Widget::RegisteredUnitMenu(
             _("Grid _units:"), "units", _wr, repr, doc) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_ox = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("_Origin X:"), _("X coordinate of grid origin"), "originx", *_rumg, _wr, repr, doc) );
+            _("_Origin X:"), _("X coordinate of grid origin"), "originx",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_x) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_oy = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("O_rigin Y:"), _("Y coordinate of grid origin"), "originy", *_rumg, _wr, repr, doc) );
+            _("O_rigin Y:"), _("Y coordinate of grid origin"), "originy",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_y) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_sy = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("Spacing _Y:"), _("Base length of z-axis"), "spacingy", *_rumg, _wr, repr, doc) );
+            _("Spacing _Y:"), _("Base length of z-axis"), "spacingy",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_y) );
     Inkscape::UI::Widget::RegisteredScalar *_rsu_ax = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalar(
             _("Angle X:"), _("Angle of x-axis"), "gridanglex", _wr, repr, doc ) );
     Inkscape::UI::Widget::RegisteredScalar *_rsu_az = Gtk::manage(  new Inkscape::UI::Widget::RegisteredScalar(
diff --git a/src/display/canvas-grid.cpp b/src/display/canvas-grid.cpp
index 2eeaa7006..0bcb6c375 100644
--- a/src/display/canvas-grid.cpp
+++ b/src/display/canvas-grid.cpp
@@ -47,6 +47,7 @@
 #include "preferences.h"
 #include "sp-namedview.h"
 #include "sp-object.h"
+#include "sp-root.h"
 #include "svg/svg-color.h"
 #include "svg/stringstream.h"
 #include "util/mathfns.h"
@@ -367,17 +368,21 @@ bool CanvasGrid::isEnabled() const
     return snapper->getEnabled();
 }
 
+// Used to shift origin when page size changed to fit drawing.
 void CanvasGrid::setOrigin(Geom::Point const &origin_px)
 {
-    Inkscape::SVGOStringStream os_x, os_y;
-    gdouble val;
+    SPRoot *root = doc->getRoot();
+    double scale_x = 1.0;
+    double scale_y = 1.0;
+    if( root->viewBox_set ) {
+        scale_x = root->viewBox.width()  / root->width.computed;
+        scale_y = root->viewBox.height() / root->height.computed;
+    }
 
-    val = origin_px[Geom::X];
-    val = Inkscape::Util::Quantity::convert(val, "px", gridunit);
-    os_x << val << gridunit->abbr;
-    val = origin_px[Geom::Y];
-    val = Inkscape::Util::Quantity::convert(val, "px", gridunit);
-    os_y << val << gridunit->abbr;
+    // Write out in 'user-units'
+    Inkscape::SVGOStringStream os_x, os_y;
+    os_x << origin_px[Geom::X] * scale_x;
+    os_y << origin_px[Geom::Y] * scale_y;
     repr->setAttribute("originx", os_x.str().c_str());
     repr->setAttribute("originy", os_y.str().c_str());
 }
@@ -504,33 +509,6 @@ static gboolean sp_nv_read_opacity(gchar const *str, guint32 *color)
     return TRUE;
 }
 
-/** If the passed scalar is invalid (<=0), then set the widget and the scalar
-    to use the given old value.
-
-    @param oldVal Old value to use if the new one is invalid.
-    @param pTarget The scalar to validate.
-    @param widget Widget associated with the scalar.
-*/
-static void validateScalar(double oldVal,
-                           double* pTarget)
-{
-    // Avoid nullness.
-    if ( pTarget == NULL )
-        return;
-
-    // Invalid new value?
-    if ( *pTarget <= 0 ) {
-        // If the old value is somehow invalid as well, then default to 1.
-        if ( oldVal <= 0 )
-            oldVal = 1;
-
-        // Reset the scalar and associated widget to the old value.
-        *pTarget = oldVal;
-    } //if
-
-} //validateScalar
-
-
 /** If the passed int is invalid (<=0), then set the widget and the int
     to use the given old value.
 
@@ -560,34 +538,78 @@ static void validateInt(gint oldVal,
 void
 CanvasXYGrid::readRepr()
 {
+    SPRoot *root = doc->getRoot();
+    double scale_x = 1.0;
+    double scale_y = 1.0;
+    if( root->viewBox_set ) {
+        scale_x = root->width.computed  / root->viewBox.width();
+        scale_y = root->height.computed / root->viewBox.height();
+    }
+
     gchar const *value;
+
     if ( (value = repr->attribute("originx")) ) {
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        origin[Geom::X] = q.value("px");
+
+        if( q.unit->type == UNIT_TYPE_LINEAR ) {
+            // Legacy grid not in 'user units'
+            origin[Geom::X] = q.value("px");
+        } else {
+            // Grid in 'user units'
+            origin[Geom::X] = q.quantity * scale_x;
+        }
     }
 
     if ( (value = repr->attribute("originy")) ) {
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        origin[Geom::Y] = q.value("px");
+
+        if( q.unit->type == UNIT_TYPE_LINEAR ) {
+            // Legacy grid not in 'user units'
+            origin[Geom::Y] = q.value("px");
+        } else {
+            // Grid in 'user units'
+            origin[Geom::Y] = q.quantity * scale_y;
+        }
     }
 
     if ( (value = repr->attribute("spacingx")) ) {
-        double oldVal = spacing[Geom::X];
+
+        // Ensure a valid default value
+        if( spacing[Geom::X] <= 0.0 )
+            spacing[Geom::X] = 1.0;
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        spacing[Geom::X] = q.quantity;
-        validateScalar(oldVal, &spacing[Geom::X]);
-        spacing[Geom::X] = Inkscape::Util::Quantity::convert(spacing[Geom::X], gridunit, "px");
+        // Ensure a valid new value
+        if( q.quantity > 0 ) {
+            if( q.unit->type == UNIT_TYPE_LINEAR ) {
+                // Legacy grid not in 'user units'
+                spacing[Geom::X] = q.value("px");
+            } else {
+                // Grid in 'user units'
+                spacing[Geom::X] = q.quantity * scale_x;
+            }
+        }
     }
+
     if ( (value = repr->attribute("spacingy")) ) {
-        double oldVal = spacing[Geom::Y];
+
+        // Ensure a valid default value
+        if( spacing[Geom::Y] <= 0.0 )
+            spacing[Geom::Y] = 1.0;
+
         Inkscape::Util::Quantity q = unit_table.parseQuantity(value);
-        gridunit = q.unit;
-        spacing[Geom::Y] = q.quantity;
-        validateScalar(oldVal, &spacing[Geom::Y]);
-        spacing[Geom::Y] = Inkscape::Util::Quantity::convert(spacing[Geom::Y], gridunit, "px");
+        // Ensure a valid new value
+        if( q.quantity > 0 ) {
+            if( q.unit->type == UNIT_TYPE_LINEAR ) {
+                // Legacy grid not in 'user units'
+                spacing[Geom::Y] = q.value("px");
+            } else {
+                // Grid in 'user units'
+                spacing[Geom::Y] = q.quantity * scale_y;
+            }
+        }
     }
 
     if ( (value = repr->attribute("color")) ) {
@@ -629,6 +651,10 @@ CanvasXYGrid::readRepr()
         snapper->setSnapVisibleOnly(strcmp(value,"false") != 0 && strcmp(value, "0") != 0);
     }
 
+    if ( (value = repr->attribute("units")) ) {
+        gridunit = unit_table.getUnit(value); // Display unit identifier in grid menu
+    }
+
     for (GSList *l = canvasitems; l != NULL; l = l->next) {
         sp_canvas_item_request_update ( SP_CANVAS_ITEM(l->data) );
     }
@@ -666,13 +692,17 @@ CanvasXYGrid::newSpecificWidget()
     Inkscape::UI::Widget::RegisteredUnitMenu *_rumg = Gtk::manage( new Inkscape::UI::Widget::RegisteredUnitMenu(
             _("Grid _units:"), "units", _wr, repr, doc) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_ox = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("_Origin X:"), _("X coordinate of grid origin"), "originx", *_rumg, _wr, repr, doc) );
+            _("_Origin X:"), _("X coordinate of grid origin"), "originx",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_x) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_oy = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("O_rigin Y:"), _("Y coordinate of grid origin"), "originy", *_rumg, _wr, repr, doc) );
+            _("O_rigin Y:"), _("Y coordinate of grid origin"), "originy",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_y) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_sx = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("Spacing _X:"), _("Distance between vertical grid lines"), "spacingx", *_rumg, _wr, repr, doc) );
+            _("Spacing _X:"), _("Distance between vertical grid lines"), "spacingx",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_x) );
     Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_sy = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
-            _("Spacing _Y:"), _("Distance between horizontal grid lines"), "spacingy", *_rumg, _wr, repr, doc) );
+            _("Spacing _Y:"), _("Distance between horizontal grid lines"), "spacingy",
+            *_rumg, _wr, repr, doc, Inkscape::UI::Widget::RSU_y) );
 
     Inkscape::UI::Widget::RegisteredColorPicker *_rcp_gcol = Gtk::manage(
         new Inkscape::UI::Widget::RegisteredColorPicker(
diff --git a/src/ui/widget/registered-widget.cpp b/src/ui/widget/registered-widget.cpp
index e97285de4..4065bd550 100644
--- a/src/ui/widget/registered-widget.cpp
+++ b/src/ui/widget/registered-widget.cpp
@@ -36,6 +36,8 @@
 // for interruptability bug:
 #include "display/sp-canvas.h"
 
+#include "sp-root.h"
+
 namespace Inkscape {
 namespace UI {
 namespace Widget {
@@ -203,7 +205,7 @@ RegisteredScalarUnit::~RegisteredScalarUnit()
     _value_changed_connection.disconnect();
 }
 
-RegisteredScalarUnit::RegisteredScalarUnit (const Glib::ustring& label, const Glib::ustring& tip, const Glib::ustring& key, const RegisteredUnitMenu &rum, Registry& wr, Inkscape::XML::Node* repr_in, SPDocument *doc_in)
+RegisteredScalarUnit::RegisteredScalarUnit (const Glib::ustring& label, const Glib::ustring& tip, const Glib::ustring& key, const RegisteredUnitMenu &rum, Registry& wr, Inkscape::XML::Node* repr_in, SPDocument *doc_in, RSU_UserUnits user_units)
     : RegisteredWidget<ScalarUnit>(label, tip, UNIT_TYPE_LINEAR, "", "", rum.getUnitMenu()),
       _um(0)
 {
@@ -215,6 +217,7 @@ RegisteredScalarUnit::RegisteredScalarUnit (const Glib::ustring& label, const Gl
     setUnit (rum.getUnitMenu()->getUnitAbbr());
     setDigits (2);
     _um = rum.getUnitMenu();
+    _user_units = user_units;
     _value_changed_connection = signal_value_changed().connect (sigc::mem_fun (*this, &RegisteredScalarUnit::on_value_changed));
 }
 
@@ -233,12 +236,28 @@ RegisteredScalarUnit::on_value_changed()
     _wr->setUpdating (true);
 
     Inkscape::SVGOStringStream os;
-    os << getValue("");
-    if (_um)
-        os << _um->getUnitAbbr();
+    if (_user_units != RSU_none) {
+        // Output length in 'user units', taking into account scale in 'x' or 'y'.
+        double scale = 1.0;
+        if (doc) {
+            SPRoot *root = doc->getRoot();
+            if (root->viewBox_set) {
+                if (_user_units == RSU_x) { 
+                    scale = root->viewBox.width() / root->width.computed;
+                } else {
+                    scale = root->viewBox.height() / root->height.computed;
+                }
+            }
+        }
+        os << getValue("px") * scale;
+    } else {
+        // Output using unit identifiers.
+        os << getValue("");
+        if (_um)
+            os << _um->getUnitAbbr();
+    }
 
     write_to_xml(os.str().c_str());
-
     _wr->setUpdating (false);
 }
 
diff --git a/src/ui/widget/registered-widget.h b/src/ui/widget/registered-widget.h
index 1f505a3cd..15302a165 100644
--- a/src/ui/widget/registered-widget.h
+++ b/src/ui/widget/registered-widget.h
@@ -206,6 +206,14 @@ protected:
     void on_changed();
 };
 
+// Allow RegisteredScalarUnit to output lengths in 'user units' (which may have direction dependent
+// scale factors).
+enum RSU_UserUnits {
+    RSU_none,
+    RSU_x,
+    RSU_y
+};
+
 class RegisteredScalarUnit : public RegisteredWidget<ScalarUnit> {
 public:
     ~RegisteredScalarUnit();
@@ -215,12 +223,14 @@ public:
                            const RegisteredUnitMenu &rum,
                            Registry& wr,
                            Inkscape::XML::Node* repr_in = NULL,
-                           SPDocument *doc_in = NULL );
+                           SPDocument *doc_in = NULL,
+                           RSU_UserUnits _user_units = RSU_none );
 
 protected:
     sigc::connection  _value_changed_connection;
     UnitMenu         *_um;
     void on_value_changed();
+    RSU_UserUnits _user_units;
 };
 
 class RegisteredScalar : public RegisteredWidget<Scalar> {