C++, Spec: add support for automatic word wrap

Specification.rst

@@ -491,6 +491,8 @@ Text Flags
 +===========+===================================================+
 | ``0``     | Text is dark, background is white                 |
 +-----------+---------------------------------------------------+
+| ``1``     | Enable automatic word wrap                        |
++-----------+---------------------------------------------------+
 | ``1`` ..  | Reserved for future use                           |
 | ``7``     |                                                   |
 +-----------+---------------------------------------------------+

cpp/src/monoformat_parseonly.cpp

@@ -1109,7 +1109,61 @@ std::expected<void, ParseError> handleClippedText(std::span<std::byte const>& bu
 
     ClippedImage target{screen, *x, *y, *width, *height};
     auto renderer = FontRenderer{fontData}.withIgnoreUnknownChars(true);
+    if (textFlags.autoWordWrap) {
+        auto dimensions = renderer.getRenderedDimensions(text, Point{0, 0});
+        if (!dimensions) {
+            return {};
+        }
+        std::int32_t y = 0;
+        while (dimensions->boundingBox && dimensions->boundingBox->size.width > (*width)) {
+            std::size_t pos = text.find('\n');
+            if (pos == std::string_view::npos) {
+                pos = text.size();
+            }
+            std::string_view currentLine = text.substr(0, pos);
+            if (pos < text.size()) {
+                text = text.substr(pos + 1);
+            } else {
+                text = text.substr(pos);
+            }
+            while (currentLine.size() > 0) {
+                dimensions = renderer.getRenderedDimensions(currentLine, Point{0, 0});
+                if (!dimensions) {
+                    return {};
+                }
+                std::size_t pos = currentLine.size();
+                while (pos > 0 && dimensions->boundingBox && dimensions->boundingBox->size.width > (*width)) {
+                    std::size_t prevPos = pos;
+                    pos = currentLine.rfind(' ', prevPos - 1);
+                    if (pos == std::string_view::npos) {
+                        pos = prevPos;
+                        break;
+                    }
+                    dimensions = renderer.getRenderedDimensions(currentLine.substr(0, pos), Point{0, 0});
+                    if (!dimensions) {
+                        return {};
+                    }
+                }
+                renderer.render(currentLine.substr(0, pos), Point{0, y + static_cast<std::int32_t>(renderer.lineHeight() - 2)}, target, fgColor, bgColor);
+                y += renderer.lineHeight();
+                if (pos < currentLine.size()) {
+                    currentLine = currentLine.substr(pos + 1);
+                } else {
+                    currentLine = currentLine.substr(pos);
+                }
+            }
+            dimensions = renderer.getRenderedDimensions(text, Point{0, 0});
+            if (!dimensions) {
+                return {};
+            }
+        }
+        if (text.size() > 0) {
+            renderer.render(text, Point{0, y + static_cast<std::int32_t>(renderer.lineHeight() - 2)}, target, fgColor, bgColor);
+            y += renderer.lineHeight();
+        }
+    } else {
         renderer.render(text, Point{0, static_cast<std::int32_t>(renderer.lineHeight() - 2)}, target, fgColor, bgColor);
+    }
 
     return {};
 }

cpp/src/monoformat_schema.hpp

@@ -101,17 +101,20 @@ struct FillFlags {
 
 struct TextFlags {
     bool dark{};
+    bool autoWordWrap{};
 
     TextFlags() = default;
 
     explicit TextFlags(std::uint8_t flags) noexcept
         : dark{isBitSet(flags, 0)}
+        , autoWordWrap{isBitSet(flags, 1)}
     {
     }
 
     explicit operator std::uint8_t() const noexcept {
         std::uint8_t result{};
         maybeSetBit(result, 0, dark);
+        maybeSetBit(result, 1, autoWordWrap);
         return result;
     }
 };

cpp/src/monoformat_structured.cpp

@@ -42,7 +42,7 @@ NLOHMANN_JSON_SERIALIZE_ENUM(FillPattern, {
 NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(ScrollFlags, endless, invertDirection, padBefore, padAfter)
 NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(LineFlags, dark)
 NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(FillFlags, dark)
-NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(TextFlags, dark)
+NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(TextFlags, dark, autoWordWrap)
 NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(TimeDisplayFlags, use12h, showHours, showMinutes, showSeconds)
 
 ImageElement::ImageElement(std::uint16_t x, std::uint16_t y, std::uint16_t width, std::uint16_t height)
@@ -1466,8 +1466,63 @@ void ClippedTextElement::drawTo(OneBitBufferInterface* imageBuffer, std::size_t
     bool fgColor = !m_textFlags.dark;
 
     auto renderer = FontRenderer{fontData}.withIgnoreUnknownChars(true);
+    if (m_textFlags.autoWordWrap) {
+        std::string_view text = m_text;
+        auto dimensions = renderer.getRenderedDimensions(text, Point{0, 0});
+        if (!dimensions) {
+            return;
+        }
+        std::int32_t y = 0;
+        while (dimensions->boundingBox && dimensions->boundingBox->size.width > m_width) {
+            std::size_t pos = text.find('\n');
+            if (pos == std::string_view::npos) {
+                pos = text.size();
+            }
+            std::string_view currentLine = text.substr(0, pos);
+            if (pos < text.size()) {
+                text = text.substr(pos + 1);
+            } else {
+                text = text.substr(pos);
+            }
+            while (currentLine.size() > 0) {
+                dimensions = renderer.getRenderedDimensions(currentLine, Point{0, 0});
+                if (!dimensions) {
+                    return;
+                }
+                std::size_t pos = currentLine.size();
+                while (pos > 0 && dimensions->boundingBox && dimensions->boundingBox->size.width > m_width) {
+                    std::size_t prevPos = pos;
+                    pos = currentLine.rfind(' ', prevPos - 1);
+                    if (pos == std::string_view::npos) {
+                        pos = prevPos;
+                        break;
+                    }
+                    dimensions = renderer.getRenderedDimensions(currentLine.substr(0, pos), Point{0, 0});
+                    if (!dimensions) {
+                        return;
+                    }
+                }
+                renderer.render(currentLine.substr(0, pos), Point{0, y + static_cast<std::int32_t>(renderer.lineHeight() - 2)}, target, fgColor, bgColor);
+                y += renderer.lineHeight();
+                if (pos < currentLine.size()) {
+                    currentLine = currentLine.substr(pos + 1);
+                } else {
+                    currentLine = currentLine.substr(pos);
+                }
+            }
+            dimensions = renderer.getRenderedDimensions(text, Point{0, 0});
+            if (!dimensions) {
+                return;
+            }
+        }
+        if (text.size() > 0) {
+            renderer.render(text, Point{0, y + static_cast<std::int32_t>(renderer.lineHeight() - 2)}, target, fgColor, bgColor);
+            y += renderer.lineHeight();
+        }
+    } else {
         renderer.render(m_text, Point{0, static_cast<std::int32_t>(renderer.lineHeight() - 2)}, target, fgColor, bgColor);
     }
+}
 
 std::expected<std::unique_ptr<ClippedTextElement>, ParseError> ClippedTextElement::parse(std::span<std::byte const>& buffer, std::uint32_t formatVersion) {
     auto type = readU16LE(buffer);