SDL_ttf: Fixed overlapping letters in SDF surface text

SDL Commits
1 
From 2ed8edf358c0825cc83e32b5237be46486e4e2f3 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Fri, 7 Mar 2025 13:23:07 -0800
Subject: [PATCH] Fixed overlapping letters in SDF surface text

---
 src/SDL_ttf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/SDL_ttf.c b/src/SDL_ttf.c
index 4c0ecab9..6e1416de 100644
--- a/src/SDL_ttf.c
+++ b/src/SDL_ttf.c
@@ -566,7 +566,7 @@ static void BG_Blended_Opaque_SDF(const TTF_Image *image, Uint32 *destination, S
     while (height--) {
         /* *INDENT-OFF* */
         DUFFS_LOOP4(
-            *dst++ = ((Uint32)*src++) << 24;
+            *dst++ |= ((Uint32)*src++) << 24;
         , width);
         /* *INDENT-ON* */
         src += srcskip;
@@ -588,7 +588,7 @@ static void BG_Blended_SDF(const TTF_Image *image, Uint32 *destination, Sint32 s
     while (height--) {
         /* *INDENT-OFF* */
         DUFFS_LOOP4(
-            *dst++ = ((Uint32)*src++) << 24;
+            *dst++ |= ((Uint32)*src++) << 24;
         , width);
         /* *INDENT-ON* */
         src += srcskip;