Font:getWidth;

src/api/l_graphics_font.c

@@ -118,6 +118,16 @@ static int l_lovrFontGetLines(lua_State* L) {
   return 1;
 }
 
+static int l_lovrFontGetWidth(lua_State* L) {
+  Font* font = luax_checktype(L, 1, Font);
+  uint32_t count;
+  ColoredString stack;
+  ColoredString* strings = luax_checkcoloredstrings(L, 2, &count, &stack);
+  float width = lovrFontGetWidth(font, strings, count);
+  lua_pushnumber(L, width);
+  return 1;
+}
+
 const luaL_Reg lovrFont[] = {
   { "getRasterizer", l_lovrFontGetRasterizer },
   { "getPixelDensity", l_lovrFontGetPixelDensity },
@@ -128,6 +138,7 @@ const luaL_Reg lovrFont[] = {
   { "getDescent", l_lovrFontGetDescent },
   { "getHeight", l_lovrFontGetHeight },
   { "getKerning", l_lovrFontGetKerning },
+  { "getWidth", l_lovrFontGetWidth },
   { "getLines", l_lovrFontGetLines },
   { NULL, NULL }
 };

src/modules/graphics/graphics.c

@@ -1992,6 +1992,47 @@ float lovrFontGetKerning(Font* font, uint32_t left, uint32_t right) {
   return kerning.f32;
 }
 
+float lovrFontGetWidth(Font* font, ColoredString* strings, uint32_t count) {
+  float x = 0.f;
+  float maxWidth = 0.f;
+  float space = lovrFontGetGlyph(font, ' ', NULL)->advance;
+
+  for (uint32_t i = 0; i < count; i++) {
+    size_t bytes;
+    uint32_t codepoint;
+    uint32_t previous = '\0';
+    const char* str = strings[i].string;
+    const char* end = strings[i].string + strings[i].length;
+    while ((bytes = utf8_decode(str, end, &codepoint)) > 0) {
+      if (codepoint == ' ' || codepoint == '\t') {
+        x += codepoint == '\t' ? space * 4.f : space;
+        previous = '\0';
+        str += bytes;
+        continue;
+      } else if (codepoint == '\n') {
+        maxWidth = MAX(maxWidth, x);
+        x = 0.f;
+        previous = '\0';
+        str += bytes;
+        continue;
+      } else if (codepoint == '\r') {
+        str += bytes;
+        continue;
+      }
+
+      Glyph* glyph = lovrFontGetGlyph(font, codepoint, NULL);
+
+      if (previous) x += lovrFontGetKerning(font, previous, codepoint);
+      previous = codepoint;
+
+      x += glyph->advance;
+      str += bytes;
+    }
+  }
+
+  return MAX(maxWidth, x) / font->pixelDensity;
+}
+
 void lovrFontGetLines(Font* font, ColoredString* strings, uint32_t count, float wrap, void (*callback)(void* context, const char* string, size_t length), void* context) {
   size_t totalLength = 0;
   for (uint32_t i = 0; i < count; i++) {

src/modules/graphics/graphics.h

@@ -354,6 +354,7 @@ void lovrFontSetPixelDensity(Font* font, float pixelDensity);
 float lovrFontGetLineSpacing(Font* font);
 void lovrFontSetLineSpacing(Font* font, float spacing);
 float lovrFontGetKerning(Font* font, uint32_t left, uint32_t right);
+float lovrFontGetWidth(Font* font, ColoredString* strings, uint32_t count);
 void lovrFontGetLines(Font* font, ColoredString* strings, uint32_t count, float wrap, void (*callback)(void* context, const char* string, size_t length), void* context);
 
 // Pass