[krita/kazakov/svg-loading] plugins/tools/defaulttool/defaulttool: Add more feedback on disabling "Uniform Scaling" mode

[Dmitry Kazakov]

Git commit b128126189b5b8f86902ec23311a9efb14f5c230 by Dmitry Kazakov.
Committed on 30/12/2016 at 09:51.
Pushed by dkazakov into branch 'kazakov/svg-loading'.

Add more feedback on disabling "Uniform Scaling" mode

Uniform Scaling mode means that your shape is not just "resized", but
"transformed" using a uniform transformation.

When you "resize" (uniform scaling disabled) a shape, you basically
change its local width and height (even when the shape is rotated
using some embedded transformation). Resizing can never shear or deform
your shape, that is a resized rectangle will always stay rectangular.

When you "uniform scale" a shape, you don't "resize" it, you apply a
transformation to it. That is all the small elements of the shape like
stroke, pattern and gradient will also become scaled. And if you apply
a uniform scale transform in global mode to a rotated shape, then
the shape will be scaled uniformly, and rectangle will become sheared.

NOTE1: Non-uniform scaling mode is available only when
       *one* shape is selected. "Resizing" multiple shapes
       in a non-uniform way is just not possible. Therefore the
       checkbox becomes automatically disabled when you select
       multiple shapes.

NOTE2: Groups do not support non-uniform "resizing" (see NOTE1).
       Technically, resizing of a group is just applying a common
       transformation on the top of the child shapes. Therefore, all
       the properties of the uniform scaling apply to this process.


CC:kimageshop at kde.org

M  +11   -2    plugins/tools/defaulttool/defaulttool/DefaultToolWidget.cpp
M  +1    -0    plugins/tools/defaulttool/defaulttool/DefaultToolWidget.h

https://commits.kde.org/krita/b128126189b5b8f86902ec23311a9efb14f5c230

diff --git a/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.cpp b/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.cpp
index 668e9ce562d..cee5c36805a 100644
--- a/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.cpp
+++ b/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.cpp
@@ -57,6 +57,7 @@ DefaultToolWidget::DefaultToolWidget(KoInteractionTool *tool, QWidget *parent)
     : QWidget(parent)
     , m_tool(tool)
     , m_sizeAspectLocker(new KisAspectRatioLocker())
+    , m_savedUniformScaling(false)
 {
     setupUi(this);
 
@@ -190,11 +191,19 @@ void DefaultToolWidget::slotUpdateCheckboxes()
     KoSelection *selection = m_tool->canvas()->shapeManager()->selection();
     QList<KoShape*> shapes = fetchEditableShapes(selection);
 
-    chkUniformScaling->setEnabled(shapes.size() == 1);
+    const bool uniformScalingAvailable = shapes.size() <= 1;
+
+    if (uniformScalingAvailable && !chkUniformScaling->isEnabled()) {
+        chkUniformScaling->setChecked(m_savedUniformScaling);
+        chkUniformScaling->setEnabled(uniformScalingAvailable);
+    } else if (!uniformScalingAvailable && chkUniformScaling->isEnabled()) {
+        m_savedUniformScaling = chkUniformScaling->isChecked();
+        chkUniformScaling->setChecked(true);
+        chkUniformScaling->setEnabled(uniformScalingAvailable);
+    }
 
     // TODO: not implemented yet!
     chkAnchorLock->setEnabled(false);
-    chkGlobalCoordinates->setEnabled(false);
 }
 
 void DefaultToolWidget::slotAspectButtonToggled()
diff --git a/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.h b/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.h
index 16d2d2f9397..b2b0845b2a4 100644
--- a/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.h
+++ b/plugins/tools/defaulttool/defaulttool/DefaultToolWidget.h
@@ -58,6 +58,7 @@ private Q_SLOTS:
 private:
     KoInteractionTool *m_tool;
     QScopedPointer<KisAspectRatioLocker> m_sizeAspectLocker;
+    bool m_savedUniformScaling;
 };
 
 #endif