Add GlyphArrangementOptions for addFittedText and drawFittedText

The new options can be used to affect line spacing.

modules/juce_graphics/fonts/juce_GlyphArrangementOptions.h

@@ -0,0 +1,95 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE framework.
+   Copyright (c) Raw Material Software Limited
+
+   JUCE is an open source framework subject to commercial or open source
+   licensing.
+
+   By downloading, installing, or using the JUCE framework, or combining the
+   JUCE framework with any other source code, object code, content or any other
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+   framework to you, and you must discontinue the installation or download
+   process and cease use of the JUCE framework.
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+
+   Or:
+
+   You may also use this code under the terms of the AGPLv3:
+   https://www.gnu.org/licenses/agpl-3.0.en.html
+
+   THE JUCE FRAMEWORK IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL
+   WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING WARRANTY OF
+   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.
+
+  ==============================================================================
+*/
+
+namespace juce
+{
+
+/** Options that can be used to affect the layout produced by GlyphArrangement::addFittedText.
+
+    @see GlyphArrangement::addFittedText
+*/
+class GlyphArrangementOptions
+{
+public:
+    /** We increment the distance between the baselines of subsequent lines with this value.
+
+        Line spacing is added below the line's descender, and doesn't affect the first line's
+        baseline.
+
+        The total distance between baselines is lineHeight * lineHeightMultiple + lineSpacing.
+    */
+    [[nodiscard]] GlyphArrangementOptions withLineSpacing (float x) const
+    {
+        return withMember (*this, &GlyphArrangementOptions::lineSpacing, x);
+    }
+
+    /** We multiply the original distance between the baselines of subsequent lines with this value.
+
+        The line height multiple is applied to both the ascender and descender, hence it affects
+        the first line's baseline.
+
+        The total distance between baselines is lineHeight * lineHeightMultiple + lineSpacing.
+    */
+    [[nodiscard]] GlyphArrangementOptions withLineHeightMultiple (float x) const
+    {
+        return withMember (*this, &GlyphArrangementOptions::lineHeightMultiple, x);
+    }
+
+    /** @see withLineSpacing() */
+    const auto& getLineSpacing() const        { return lineSpacing; }
+
+    /** @see withLineHeightMultiple() */
+    const auto& getLineHeightMultiple() const { return lineHeightMultiple; }
+
+    /** Equality operator. */
+    [[nodiscard]] bool operator== (const GlyphArrangementOptions& other) const;
+    /** Inequality operator. */
+    [[nodiscard]] bool operator!= (const GlyphArrangementOptions& other) const;
+    /** Less-than operator. Allows GlyphArrangementOptions to be used as keys in a map. */
+    [[nodiscard]] bool operator<  (const GlyphArrangementOptions& other) const;
+    /** Less-than-or-equal operator. */
+    [[nodiscard]] bool operator<= (const GlyphArrangementOptions& other) const;
+    /** Greater-than operator. */
+    [[nodiscard]] bool operator>  (const GlyphArrangementOptions& other) const;
+    /** Greater-than-or-equal operator. */
+    [[nodiscard]] bool operator>= (const GlyphArrangementOptions& other) const;
+
+private:
+    auto tie() const noexcept;
+
+    float lineSpacing = 0.0f;
+    float lineHeightMultiple = 1.0f;
+};
+
+} // namespace juce