Fix imprecise viewBox dimensions on page size change (bug #1235279).

Fixed bugs:
  - https://launchpad.net/bugs/1235279

(bzr r12965)

1 files changed, 18 insertions, 4 deletions

diff --git a/src/document.cpp b/src/document.cpp
index e56adee68..8b956d5e7 100644
--- a/src/document.cpp
+++ b/src/document.cpp
@@ -585,6 +585,7 @@ Inkscape::Util::Quantity SPDocument::getWidth() const
 void SPDocument::setWidth(const Inkscape::Util::Quantity &width)
 {
     gdouble old_computed = root->width.computed;
+    gdouble old_value = root->width.value;
     root->width.computed = width.value("px");
     /* SVG does not support meters as a unit, so we must translate meters to
      * cm when writing */
@@ -596,8 +597,14 @@ void SPDocument::setWidth(const Inkscape::Util::Quantity &width)
         root->width.unit = (SVGLength::Unit) width.unit->svgUnit();
     }
 
-    if (root->viewBox_set)
-        root->viewBox.setMax(Geom::Point(root->viewBox.left() + (root->width.computed / old_computed) * root->viewBox.width(), root->viewBox.bottom()));
+    if (root->viewBox_set) {
+        if (abs(old_value - root->viewBox.width()) < 0.00001) {
+            root->viewBox.setMax(Geom::Point(root->viewBox.left() + root->width.value, root->viewBox.bottom()));
+        }
+        else {
+            root->viewBox.setMax(Geom::Point(root->viewBox.left() + (root->width.computed / old_computed) * root->viewBox.width(), root->viewBox.bottom()));
+        }
+    }
 
     root->updateRepr();
 }
@@ -622,6 +629,7 @@ Inkscape::Util::Quantity SPDocument::getHeight() const
 void SPDocument::setHeight(const Inkscape::Util::Quantity &height)
 {
     gdouble old_computed = root->height.computed;
+    gdouble old_value = root->height.value;
     root->height.computed = height.value("px");
     /* SVG does not support meters as a unit, so we must translate meters to
      * cm when writing */
@@ -633,8 +641,14 @@ void SPDocument::setHeight(const Inkscape::Util::Quantity &height)
         root->height.unit = (SVGLength::Unit) height.unit->svgUnit();
     }
 
-    if (root->viewBox_set)
-        root->viewBox.setMax(Geom::Point(root->viewBox.right(), root->viewBox.top() + (root->height.computed / old_computed) * root->viewBox.height()));
+    if (root->viewBox_set) {
+        if (abs(old_value - root->viewBox.height()) < 0.00001) {
+            root->viewBox.setMax(Geom::Point(root->viewBox.right(), root->viewBox.top() + root->height.value));
+        }
+        else {
+            root->viewBox.setMax(Geom::Point(root->viewBox.right(), root->viewBox.top() + (root->height.computed / old_computed) * root->viewBox.height()));
+        }
+    }
 
     root->updateRepr();
 }