ComponentBoundsConstrainer: Add new decorator constrainer

modules/juce_audio_plugin_client/Standalone/juce_StandaloneFilterWindow.h

@@ -1089,57 +1089,17 @@ private:
         accordingly. The end result is that the peer is resized twice in a row to different sizes,
         which can appear glitchy/flickery to the user.
     */
-    struct DecoratorConstrainer : public ComponentBoundsConstrainer
+    class DecoratorConstrainer : public BorderedComponentBoundsConstrainer
     {
-        void checkBounds (Rectangle<int>& bounds,
-                          const Rectangle<int>& previousBounds,
-                          const Rectangle<int>& limits,
-                          bool isStretchingTop,
-                          bool isStretchingLeft,
-                          bool isStretchingBottom,
-                          bool isStretchingRight) override
+    public:
+        ComponentBoundsConstrainer* getWrappedConstrainer() const override
         {
-            auto* decorated = contentComponent != nullptr ? contentComponent->getEditorConstrainer()
-                                                          : nullptr;
+            return contentComponent != nullptr ? contentComponent->getEditorConstrainer() : nullptr;
+        }
 
-            if (decorated != nullptr)
-            {
-                const auto border = contentComponent->computeBorder();
-                const auto requestedBounds = bounds;
-
-                border.subtractFrom (bounds);
-                decorated->checkBounds (bounds,
-                                        border.subtractedFrom (previousBounds),
-                                        limits,
-                                        isStretchingTop,
-                                        isStretchingLeft,
-                                        isStretchingBottom,
-                                        isStretchingRight);
-                border.addTo (bounds);
-                bounds = bounds.withPosition (requestedBounds.getPosition());
-
-                if (isStretchingTop && ! isStretchingBottom)
-                    bounds = bounds.withBottomY (previousBounds.getBottom());
-
-                if (! isStretchingTop && isStretchingBottom)
-                    bounds = bounds.withY (previousBounds.getY());
-
-                if (isStretchingLeft && ! isStretchingRight)
-                    bounds = bounds.withRightX (previousBounds.getRight());
-
-                if (! isStretchingLeft && isStretchingRight)
-                    bounds = bounds.withX (previousBounds.getX());
-            }
-            else
-            {
-                ComponentBoundsConstrainer::checkBounds (bounds,
-                                                         previousBounds,
-                                                         limits,
-                                                         isStretchingTop,
-                                                         isStretchingLeft,
-                                                         isStretchingBottom,
-                                                         isStretchingRight);
-            }
+        BorderSize<int> getAdditionalBorder() const override
+        {
+            return contentComponent != nullptr ? contentComponent->computeBorder() : BorderSize<int>{};
         }
 
         void setMainContentComponent (MainContentComponent* in) { contentComponent = in; }

modules/juce_gui_basics/juce_gui_basics.cpp

@@ -268,6 +268,7 @@
 #include "keyboard/juce_ModifierKeys.cpp"
 #include "layout/juce_ComponentAnimator.cpp"
 #include "layout/juce_ComponentBoundsConstrainer.cpp"
+#include "layout/juce_BorderedComponentBoundsConstrainer.cpp"
 #include "layout/juce_ComponentBuilder.cpp"
 #include "layout/juce_ComponentMovementWatcher.cpp"
 #include "layout/juce_ConcertinaPanel.cpp"

modules/juce_gui_basics/juce_gui_basics.h

@@ -199,6 +199,7 @@ namespace juce
 #include "desktop/juce_Desktop.h"
 #include "desktop/juce_Displays.h"
 #include "layout/juce_ComponentBoundsConstrainer.h"
+#include "layout/juce_BorderedComponentBoundsConstrainer.h"
 #include "mouse/juce_ComponentDragger.h"
 #include "mouse/juce_DragAndDropTarget.h"
 #include "mouse/juce_DragAndDropContainer.h"

modules/juce_gui_basics/layout/juce_BorderedComponentBoundsConstrainer.cpp

@@ -0,0 +1,77 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library.
+   Copyright (c) 2022 - Raw Material Software Limited
+
+   JUCE is an open source library subject to commercial or open-source
+   licensing.
+
+   By using JUCE, you agree to the terms of both the JUCE 7 End-User License
+   Agreement and JUCE Privacy Policy.
+
+   End User License Agreement: www.juce.com/juce-7-licence
+   Privacy Policy: www.juce.com/juce-privacy-policy
+
+   Or: You may also use this code under the terms of the GPL v3 (see
+   www.gnu.org/licenses).
+
+   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
+   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
+   DISCLAIMED.
+
+  ==============================================================================
+*/
+
+namespace juce
+{
+
+void BorderedComponentBoundsConstrainer::checkBounds (Rectangle<int>& bounds,
+                                                      const Rectangle<int>& previousBounds,
+                                                      const Rectangle<int>& limits,
+                                                      bool isStretchingTop,
+                                                      bool isStretchingLeft,
+                                                      bool isStretchingBottom,
+                                                      bool isStretchingRight)
+{
+    if (auto* decorated = getWrappedConstrainer())
+    {
+        const auto border = getAdditionalBorder();
+        const auto requestedBounds = bounds;
+
+        border.subtractFrom (bounds);
+        decorated->checkBounds (bounds,
+                                border.subtractedFrom (previousBounds),
+                                limits,
+                                isStretchingTop,
+                                isStretchingLeft,
+                                isStretchingBottom,
+                                isStretchingRight);
+        border.addTo (bounds);
+        bounds = bounds.withPosition (requestedBounds.getPosition());
+
+        if (isStretchingTop && ! isStretchingBottom)
+            bounds = bounds.withBottomY (previousBounds.getBottom());
+
+        if (! isStretchingTop && isStretchingBottom)
+            bounds = bounds.withY (previousBounds.getY());
+
+        if (isStretchingLeft && ! isStretchingRight)
+            bounds = bounds.withRightX (previousBounds.getRight());
+
+        if (! isStretchingLeft && isStretchingRight)
+            bounds = bounds.withX (previousBounds.getX());
+    }
+    else
+    {
+        ComponentBoundsConstrainer::checkBounds (bounds,
+                                                 previousBounds,
+                                                 limits,
+                                                 isStretchingTop,
+                                                 isStretchingLeft,
+                                                 isStretchingBottom,
+                                                 isStretchingRight);
+    }
+}
+
+} // namespace juce

modules/juce_gui_basics/layout/juce_BorderedComponentBoundsConstrainer.h

@@ -0,0 +1,69 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library.
+   Copyright (c) 2022 - Raw Material Software Limited
+
+   JUCE is an open source library subject to commercial or open-source
+   licensing.
+
+   By using JUCE, you agree to the terms of both the JUCE 7 End-User License
+   Agreement and JUCE Privacy Policy.
+
+   End User License Agreement: www.juce.com/juce-7-licence
+   Privacy Policy: www.juce.com/juce-privacy-policy
+
+   Or: You may also use this code under the terms of the GPL v3 (see
+   www.gnu.org/licenses).
+
+   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
+   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
+   DISCLAIMED.
+
+  ==============================================================================
+*/
+
+namespace juce
+{
+
+//==============================================================================
+/**
+    A ComponentBoundsConstrainer that can be used to add a constant border onto another
+    ComponentBoundsConstrainer.
+
+    This is useful when trying to constrain the size of a resizable window or
+    other component that wraps a constrained component, such as a plugin
+    editor.
+
+    @see ResizableCornerComponent, ResizableBorderComponent, ResizableWindow,
+         ComponentBoundsConstrainer
+
+    @tags{GUI}
+*/
+class JUCE_API  BorderedComponentBoundsConstrainer : public ComponentBoundsConstrainer
+{
+public:
+    /** Default constructor. */
+    BorderedComponentBoundsConstrainer() = default;
+
+    /** Returns a pointer to another constrainer that will be used as the
+        base for any resizing operations.
+    */
+    virtual ComponentBoundsConstrainer* getWrappedConstrainer() const = 0;
+
+    /** Returns the border that should be applied to the constrained bounds. */
+    virtual BorderSize<int> getAdditionalBorder() const = 0;
+
+    /** @internal */
+    void checkBounds (Rectangle<int>& bounds,
+                      const Rectangle<int>& previousBounds,
+                      const Rectangle<int>& limits,
+                      bool isStretchingTop,
+                      bool isStretchingLeft,
+                      bool isStretchingBottom,
+                      bool isStretchingRight) override;
+
+    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (BorderedComponentBoundsConstrainer)
+};
+
+} // namespace juce