Modified Preview Canvas

- Now the Preview can show free space around the image (the image's
corner will coincide with the center of the preview area)
- Editing objects can now be manipulated in this free space
- The editing mechanism has been split : it was completely handled in
rtengine before, now rtengine still handle the pipette's data provider,
but rtgui now handle the objects data provider.
- Bugfix: when using coarse rotate in the Editor panel, the Gradient
widgets are now correctly displayed

rtengine/pipettebuffer.h

@@ -0,0 +1,96 @@
+/*
+ *  This file is part of RawTherapee.
+ *
+ *  Copyright (c) 2004-2010 Gabor Horvath <hgabor@rawtherapee.com>
+ *
+ *  RawTherapee is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  RawTherapee is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef _PIPETTEBUFFER_H_
+#define _PIPETTEBUFFER_H_
+
+#include "../rtgui/edit.h"
+#include "array2D.h"
+#include "iimage.h"
+#include "coord.h"
+
+namespace rtengine
+{
+
+/// @brief Structure that contains information about and pointers to the Edit buffer
+class PipetteBuffer
+{
+protected:
+
+    // To avoid duplicated information, we points to a EditDataProvider that contains the current EditSubscriber
+    // instead of pointing to the EditSubscriber directly
+    ::EditDataProvider* dataProvider;
+
+    // TODO: Unfortunately, buffer can be of several type, each one representing a floating point image. Maybe we could unify everything one day!?
+    // Only one of the following pointers will be allocated at a time, if any; "one chunk" allocation
+    Imagefloat* imgFloatBuffer;
+    LabImage* LabBuffer;
+    PlanarWhateverData<float> singlePlaneBuffer;
+
+    bool ready;  // flag that indicates if the _pipette_ buffer is ready
+
+    void createBuffer(int width, int height);
+    void resize(int newWidth, int newHeight, EditSubscriber* newSubscriber);
+    void resize(int newWidth, int newHeight);
+    void flush();
+
+public:
+    PipetteBuffer(::EditDataProvider *dataProvider);
+    ~PipetteBuffer();
+
+    /** @brief Getter to know if the pipette buffer is correctly filled */
+    bool isReady()
+    {
+        return ready;
+    }
+
+    /** @brief Setter to tell that the pipette buffer is correctly filled
+     *  You have to use this method once the pipette is filled, so it can be read. */
+    void setReady()
+    {
+        ready = true;
+    }
+
+    ::EditDataProvider* getDataProvider()
+    {
+        return dataProvider;
+    }
+    EditUniqueID getEditID();
+    Imagefloat* getImgFloatBuffer()
+    {
+        return imgFloatBuffer;
+    }
+    LabImage* getLabBuffer()
+    {
+        return LabBuffer;
+    }
+    PlanarWhateverData<float>* getSinglePlaneBuffer()
+    {
+        return &singlePlaneBuffer;
+    }
+
+    // return true if the buffer has been allocated
+    bool bufferCreated();
+
+    // get the pipette values
+    void getPipetteData(float* v, int x, int y, int squareSize);
+};
+
+}
+
+#endif