Add command to scale the image

The command lets the user choose either the new length or width of the
image. Afterwards it adjusts the ppi value to get close to the user
entered size.

Also adds the new feature to the documentation

 #7

README.md

@@ -69,6 +69,8 @@ The name of the imported image object will be taken from the image file.
 
 The image is also shown in the 3D View. The image is converted to grayscale and the size is the same as the final geometry created with the `Create Box` command. So you get a feeling for the final geometry even before creating it. The image is displayed 1 mm beneath the XY Plane. This makes it possible to trace over the image when needed.
 
+To hide or show the image in the 3D view, select it and hit `Space`.
+
 **The pixel data whil be computed every time you recompute the image object!** This can happen when you change some settings of the image or force a recompute of the whole document.
 For performance reasons the calculated point cloud is stored inside the FreeCAD file. So your files can get pretty big real fast when you import big images.
 
@@ -120,6 +122,16 @@ The name of the resulting mesh will be taken from the selected LithophaneImage.
 
 More Features might follow: https://github.com/furti/FreeCAD-Lithophane/issues/15
 
+### Scale Image
+![Scale Image](./Resources/Icons/Scale.svg)
+
+This command can be used to scale the selected LithophaneImage. When executed, a task dialog will be shown. You can enter either the new length or width of the image. Entering one value will adjust the other value accordingly.
+
+ - OK will apply the new size to the image
+ - Cancel will simply close the dialog and nothing will be applied
+
+![Scale Dialog](./Resources/Documentation/scale_dialog.png)
+
 ### Make Solid
 ![Import Image](./Resources/Icons/MakeSolid.svg)
 

Resources/UI/scale_dialog.ui

@@ -0,0 +1,72 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>Dialog</class>
+ <widget class="QDialog" name="Dialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>400</width>
+    <height>300</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Dialog</string>
+  </property>
+  <layout class="QFormLayout" name="formLayout">
+   <item row="1" column="0">
+    <widget class="QLabel" name="label">
+     <property name="text">
+      <string>Length (X)</string>
+     </property>
+    </widget>
+   </item>
+   <item row="1" column="1">
+    <widget class="QDoubleSpinBox" name="LengthBox">
+     <property name="suffix">
+      <string>mm</string>
+     </property>
+     <property name="maximum">
+      <double>100000.000000000000000</double>
+     </property>
+    </widget>
+   </item>
+   <item row="2" column="1">
+    <widget class="QDoubleSpinBox" name="WidthBox">
+     <property name="suffix">
+      <string>mm</string>
+     </property>
+    </widget>
+   </item>
+   <item row="3" column="0" colspan="2">
+    <widget class="Line" name="line">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+    </widget>
+   </item>
+   <item row="2" column="0">
+    <widget class="QLabel" name="label_2">
+     <property name="text">
+      <string>Width (Y)</string>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="0" colspan="2">
+    <widget class="QLabel" name="InfoLabel">
+     <property name="font">
+      <font>
+       <weight>75</weight>
+       <bold>true</bold>
+      </font>
+     </property>
+     <property name="text">
+      <string/>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>

lithophane_image.py

@@ -11,7 +11,7 @@
 
 from image_viewer import ImageViewer
 from utils.geometry_utils import pointCloudToLines
-from lithophane_utils import toChunks, tupleToVector, vectorToTuple, convertImageToTexture
+from lithophane_utils import toChunks, tupleToVector, vectorToTuple, convertImageToTexture, recomputeView
 from utils.timer import Timer, computeOverallTime
 import utils.qtutils as qtutils
 
@@ -225,6 +225,12 @@ def execute(self, fp):
 
         fp.UpdateNotifier += 1
 
+    def length(self):
+        return self.lines[-1][-1].x
+
+    def width(self):
+        return self.lines[-1][-1].y
+
     def __getstate__(self):
         '''Store the image as base64 inside the document'''
 
@@ -257,7 +263,7 @@ def __setstate__(self,state):
         self.isLithophaneImage = True
 
         return None
-
+    
 class ViewProviderLithophaneImage:
     def __init__(self, vobj):
         '''Only set our viewprovider as proxy. No properties needed'''
@@ -314,11 +320,12 @@ def updateData(self, fp, prop):
 
             self.texture.image = convertImageToTexture(lithophaneImage.image)
 
-            topRight = lithophaneImage.lines[-1][-1]
+            length = lithophaneImage.length()
+            width = lithophaneImage.width()
 
-            self.coords.point.set1Value(1, topRight.x, 0, -1)
-            self.coords.point.set1Value(2, topRight.x, topRight.y, -1)
-            self.coords.point.set1Value(3, 0, topRight.y, -1)
+            self.coords.point.set1Value(1, length, 0, -1)
+            self.coords.point.set1Value(2, length, width, -1)
+            self.coords.point.set1Value(3, 0, width, -1)
 
         return
 
@@ -344,6 +351,8 @@ def createImage(imagePath):
     image = LithophaneImage(a, imagePath)
     ViewProviderLithophaneImage(a.ViewObject)
 
+    recomputeView()
+
     return image
 
 if __name__ == "__main__":

lithophane_utils.py

@@ -12,21 +12,29 @@ def recomputeView():
     FreeCADGui.activeDocument().activeView().viewAxonometric()
     FreeCADGui.SendMsgToActiveView("ViewFit")
 
-def findSelectedImage():
+def findSelectedImage(includeObject=False):
   selection = FreeCADGui.Selection.getSelection()
+
+  if includeObject:
+    notFound = (None, None, None)
+  else:
+    notFound = (None, None)
 
   if len(selection) != 1:
-    return (None, None)
+    return notFound
 
   selectedObject = selection[0]
 
   if not hasattr(selectedObject, 'Proxy') or selectedObject.Proxy is None:
-    return (None, None)
+    return notFound
 
   if not hasattr(selectedObject.Proxy, 'isLithophaneImage') or not selectedObject.Proxy.isLithophaneImage:
-    return (None, None)
+    return notFound
 
-  return (selection[0].Proxy, selection[0].Label)
+  if includeObject:
+    return (selection[0].Proxy, selection[0].Label, selection[0])
+  else:
+    return (selection[0].Proxy, selection[0].Label)
 
 def findSelectedMesh():
   selection = FreeCADGui.Selection.getSelection()

scale.py

@@ -0,0 +1,96 @@
+import FreeCAD, FreeCADGui
+
+import lithophane_utils
+from utils.resource_utils import iconPath, uiPath
+from utils.format_utils import formatLength
+import utils.qtutils as qtutils
+
+class ScalePanel():
+    def __init__(self, image, freeCadObject):
+        self.image = image
+        self.freeCadObject = freeCadObject
+        self.originalLength = image.length()
+        self.originalWidth = image.width()
+        self.scaleFactor = 1
+
+        self.form = FreeCADGui.PySideUic.loadUi(uiPath('scale_dialog.ui'))
+
+        self.LengthBox = self.form.LengthBox
+        self.WidthBox = self.form.WidthBox
+        self.InfoLabel = self.form.InfoLabel
+        self.LengthBox.setValue(self.originalLength)
+        self.WidthBox.setValue(self.originalWidth)
+
+        self.LengthBox.valueChanged.connect(self.lengthChanged)
+        self.WidthBox.valueChanged.connect(self.widthChanged)
+
+    def accept(self):
+        FreeCADGui.Control.closeDialog()
+
+        if self.scaleFactor != 1:
+            self.InfoLabel.setText('The image is recomputed. This might take a while...')
+            qtutils.processEvents()
+
+            originalPpi = self.freeCadObject.ppi
+
+            # smaller ppi means larger image. So division not multiplication
+            self.freeCadObject.ppi = originalPpi / self.scaleFactor
+
+            lithophane_utils.recomputeView()
+
+    def reject(self):
+        FreeCADGui.Control.closeDialog()
+
+    def lengthChanged(self):
+        self.updateScaleFactor(self.originalLength, self.LengthBox.value())
+
+        newWidth = self.originalWidth * self.scaleFactor
+
+        if self.WidthBox.value() != newWidth:
+            self.WidthBox.setValue(newWidth)
+
+    def widthChanged(self):
+        self.updateScaleFactor(self.originalWidth, self.WidthBox.value())
+
+        newLength = self.originalLength * self.scaleFactor
+
+        if self.LengthBox.value() != newLength:
+            self.LengthBox.setValue(newLength)
+
+    def updateScaleFactor(self, old, new):
+        self.scaleFactor = new / old
+
+class ScaleCommand:
+    toolbarName = 'Image_Tools'
+    commandName = 'Scale_Image'
+
+    def GetResources(self):
+        return {'MenuText': "Scale",
+                'ToolTip' : "Adjusts the dpi value to scale the final geometry",
+                'Pixmap': iconPath('Scale.svg')}
+
+    def Activated(self):
+        (image, label, freeCadObject) = lithophane_utils.findSelectedImage(includeObject=True)
+
+        if image is None:
+          qtutils.showInfo("No LithophaneImage selected", "Select exactly one LithophaneImage to continue")
+
+          return
+
+        panel = ScalePanel(image, freeCadObject)
+        FreeCADGui.Control.showDialog(panel)
+
+    def IsActive(self):
+        """There should be at least an active document."""
+        return not FreeCAD.ActiveDocument is None
+
+if __name__ == "__main__":
+    command = ScaleCommand();
+
+    if command.IsActive():
+        command.Activated()
+    else:
+        qtutils.showInfo("No open Document", "There is no open document")
+else:
+    import toolbars
+    toolbars.toolbarManager.registerCommand(ScaleCommand())

toolbars.py

@@ -13,6 +13,7 @@ def registerCommand(self, command):
 # geometry tools
 import import_image
 import create_box
+import scale
 
 # solid tools
 import make_solid

utils/resource_utils.py

@@ -1,9 +1,16 @@
 import FreeCAD
 from os import path
 
-utils_path = path.join(path.dirname(path.realpath(__file__)), '../Resources/Icons')
+resources_path = path.join(path.dirname(path.realpath(__file__)), '../Resources')
+icons_path = path.join(resources_path, 'Icons')
+ui_path = path.join(resources_path, 'UI')
 
 def iconPath(name):
-    f = path.join(utils_path, name)
+    f = path.join(icons_path, name)
+
+    return f
+
+def uiPath(name):
+    f = path.join(ui_path, name)
 
     return f