Added new "Preprocess WB" parameter in the Raw toolpanel, just below "Raw White Points" tool. Allows to choose between "Camera" and "Auto" (average-based) raw channel multipliers, and to apply custom compesation factors.

Fixes #5616

rtgui/preprocesswb.h

@@ -0,0 +1,52 @@
+/*
+ *  This file is part of RawTherapee.
+ *
+ *  Copyright (c) 2020 Alberto Romei <aldrop8@gmail.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 <https://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <gtkmm.h>
+
+#include "adjuster.h"
+#include "toolpanel.h"
+
+class PreprocessWB final:
+    public ToolParamBlock,
+    public AdjusterListener,
+    public FoldableToolPanel
+{
+
+private:
+    const rtengine::ProcEvent evPreprocessWBMode, evPreprocessWBMults;
+
+    MyComboBoxText* mode;
+
+    Adjuster* red;
+    Adjuster* blue;
+
+public:
+
+    PreprocessWB();
+
+    void read(const rtengine::procparams::ProcParams* pp, const ParamsEdited* pedited = nullptr) override;
+    void write(rtengine::procparams::ProcParams* pp, ParamsEdited* pedited = nullptr) override;
+    void setBatchMode(bool batchMode) override;
+    void setDefaults(const rtengine::procparams::ProcParams* defParams, const ParamsEdited* pedited = nullptr) override;
+    void adjusterChanged(Adjuster* a, double newval) override;
+    void setAdjusterBehavior(bool add);
+    void trimValues(rtengine::procparams::ProcParams* pp) override;
+    void modeChanged();
+};