From 3f2f8f9b57a5b2e7230e6265596e7bfdb1e6e21d Mon Sep 17 00:00:00 2001
From: Leon Styhre <leon@leonstyhre.com>
Date: Tue, 20 Aug 2024 17:16:19 +0200
Subject: [PATCH] Fixed a special line wrapping scenario where a trailing space
 should be removed

---
 es-core/src/resources/Font.cpp | 37 +++++++++++++++++++++++++++-------
 es-core/src/resources/Font.h   |  9 +++++----
 2 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/es-core/src/resources/Font.cpp b/es-core/src/resources/Font.cpp
index 2a75a3f0a..e3e8616d1 100644
--- a/es-core/src/resources/Font.cpp
+++ b/es-core/src/resources/Font.cpp
@@ -292,7 +292,7 @@ TextCache* Font::buildTextCache(const std::string& text,
 
     std::vector<ShapeSegment> segmentsHB;
     shapeText(text, segmentsHB);
-    wrapText(segmentsHB, maxLength, height, lineSpacing, multiLine);
+    wrapText(segmentsHB, maxLength, height, lineSpacing, multiLine, needGlyphsPos);
 
     size_t segmentIndex {0};
     float x {0.0f};
@@ -370,6 +370,13 @@ TextCache* Font::buildTextCache(const std::string& text,
                 isNewLine = true;
                 continue;
             }
+            else if (segment.glyphIndexes[cursor].second == -1) {
+                // Special scenario where a space glyph at the end of a segment should be omitted,
+                // in which case it's set to -1 advance in wrapText(). We can't set it to 0 as
+                // that's actually a valid value for some fonts such as when having an apostrophe
+                // followed by a comma.
+                continue;
+            }
 
             if (segment.doShape)
                 glyph =
@@ -496,7 +503,7 @@ float Font::getSizeReference()
         }
     }
 
-    mSizeReference = advance;
+    mSizeReference = static_cast<float>(advance);
     return mSizeReference;
 }
 
@@ -745,7 +752,8 @@ void Font::wrapText(std::vector<ShapeSegment>& segmentsHB,
                     float maxLength,
                     const float maxHeight,
                     const float lineSpacing,
-                    const bool multiLine)
+                    const bool multiLine,
+                    const bool needGlyphsPos)
 {
     std::vector<ShapeSegment> resultSegments;
 
@@ -773,8 +781,8 @@ void Font::wrapText(std::vector<ShapeSegment>& segmentsHB,
             (segmentsHB.size() == 1 && segmentsHB.front().shapedWidth <= maxLength))
             return;
 
-        // Additionally this captures shorter multi-segment text that does not require more involved
-        // line breaking or abbreviations.
+        // Additionally this captures shorter single-line multi-segment text that does not require
+        // more involved line breaking or abbreviations.
         float combinedWidth {0.0f};
         bool hasNewline {false};
         for (auto& segment : segmentsHB) {
@@ -911,9 +919,24 @@ void Font::wrapText(std::vector<ShapeSegment>& segmentsHB,
                                 newShapedWidth -= newSegment.glyphIndexes.back().second;
                                 newSegment.glyphIndexes.pop_back();
                             }
+                            // If all glyphs were removed and the last character of the previous
+                            // segment was a space, then set its advance to -1 so it gets excluded
+                            // in buildTextCache(). That is, unless needGlyphPos is true as that
+                            // means the text is needed for TextEditComponent and should therefore
+                            // not be altered.
+                            if (!needGlyphsPos && newSegment.glyphIndexes.empty() &&
+                                !resultSegments.empty()) {
+                                if (resultSegments.back().glyphIndexes.back().first ==
+                                    resultSegments.back().spaceChar) {
+                                    resultSegments.back().shapedWidth -=
+                                        resultSegments.back().glyphIndexes.back().second;
+                                    resultSegments.back().glyphIndexes.back().second = -1;
+                                }
+                            }
                         }
 
-                        newSegment.length = newSegment.glyphIndexes.size();
+                        newSegment.length =
+                            static_cast<unsigned int>(newSegment.glyphIndexes.size());
                         newSegment.shapedWidth = newShapedWidth;
 
                         if (newSegment.glyphIndexes.size() != 0)
@@ -974,7 +997,7 @@ void Font::wrapText(std::vector<ShapeSegment>& segmentsHB,
         else
             lastSegmentSpace = false;
 
-        newSegment.length = newSegment.glyphIndexes.size();
+        newSegment.length = static_cast<unsigned int>(newSegment.glyphIndexes.size());
         newSegment.shapedWidth = newShapedWidth;
 
         if (newSegment.glyphIndexes.size() != 0)
diff --git a/es-core/src/resources/Font.h b/es-core/src/resources/Font.h
index 8397c54fe..9c8bc33d4 100644
--- a/es-core/src/resources/Font.h
+++ b/es-core/src/resources/Font.h
@@ -166,7 +166,7 @@ private:
         FontTexture* texture;
         hb_font_t* fontHB;
         glm::vec2 texPos;
-        glm::vec2 texSize; // In texels.
+        glm::vec2 texSize;
         glm::ivec2 advance;
         glm::ivec2 bearing;
         int rows;
@@ -217,9 +217,10 @@ private:
     // Inserts newlines to make text wrap properly and also abbreviates when necessary.
     void wrapText(std::vector<ShapeSegment>& segmentsHB,
                   float maxLength,
-                  const float maxHeight = 0.0f,
-                  const float lineSpacing = 1.5f,
-                  const bool multiLine = false);
+                  const float maxHeight,
+                  const float lineSpacing,
+                  const bool multiLine,
+                  const bool needGlyphsPos);
 
     // Completely recreate the texture data for all glyph atlas entries.
     void rebuildTextures();