From 83c8984c74ba3ecef42fc78c4571bb1b25dcce4e Mon Sep 17 00:00:00 2001
From: Vincent Wei <vincent@minigui.org>
Date: Sun, 13 Jan 2019 16:59:36 +0800
Subject: [PATCH] support flipping glyph for subpixel rendering

---
 src/font/logfont.c |  4 +++-
 src/newgdi/glyph.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/src/font/logfont.c b/src/font/logfont.c
index a3f2cfaa..077803ba 100644
--- a/src/font/logfont.c
+++ b/src/font/logfont.c
@@ -74,7 +74,6 @@ static PLOGFONT gdiCreateLogFont (const char* type, const char* family,
     int sbc_value, mbc_value = 0;
     char dev_family [LEN_FONT_NAME + 1];
     DEVFONT* sbc_devfont, *mbc_devfont;
-    DWORD glyph_bmptype;
 
     // is valid style?
     if (style == 0xFFFFFFFF)
@@ -225,6 +224,7 @@ static PLOGFONT gdiCreateLogFont (const char* type, const char* family,
     /*reset size of logfont*/
     log_font->size = log_font->ascent + log_font->descent;
 
+#if 0 // VincentWei: support fillping for subpixel renderer
     /* reset style of logfont */
     /* remove HORZVERT style if weight is subpixel */
     if ((log_font->style & FS_RENDER_MASK) == FS_RENDER_SUBPIXEL) {
@@ -233,6 +233,7 @@ static PLOGFONT gdiCreateLogFont (const char* type, const char* family,
     }
 
     /* remove HORZVERT style if the glyph bmptype is subpixel */
+    DWORD glyph_bmptype;
     glyph_bmptype = log_font->sbc_devfont->font_ops->get_glyph_type
                 (log_font, log_font->sbc_devfont) & DEVFONTGLYPHTYPE_MASK_BMPTYPE;
     if (glyph_bmptype == GLYPHBMP_TYPE_SUBPIXEL) {
@@ -244,6 +245,7 @@ static PLOGFONT gdiCreateLogFont (const char* type, const char* family,
         if (glyph_bmptype == GLYPHBMP_TYPE_SUBPIXEL)
             log_font->style &= ~FS_FLIP_HORZVERT;
     }
+#endif
 
     _DBG_PRINTF ("FONT>LogFont: created info: type: %s, family: %s, style: %p, charset: %s, size: %d.\n",
                     log_font->type, log_font->family, (PVOID)log_font->style, log_font->charset,
diff --git a/src/newgdi/glyph.c b/src/newgdi/glyph.c
index 062fbd09..dda50a32 100644
--- a/src/newgdi/glyph.c
+++ b/src/newgdi/glyph.c
@@ -3647,6 +3647,52 @@ static BYTE* _gdi_flip_greybitmap_horz (BYTE* src_bits, const SIZE* size, int pi
     return _scaled_bits;
 }
 
+static BYTE* _gdi_flip_subpixels_horz (BYTE* src_bits, const SIZE* size, int pitch)
+{
+    BYTE* dst_line;
+    const BYTE* src_line;
+    int i, j;
+    BYTE* inter_line;
+
+    src_line = src_bits;
+    if (src_bits != _scaled_bits) {
+        _prepare_scaled_bits (pitch * (size->cy + 1));
+        if (_scaled_bits == NULL)
+            return NULL;
+
+        inter_line = NULL;
+        dst_line = _scaled_bits;
+    }
+    else {
+        inter_line = src_bits + (pitch * size->cy);
+        dst_line = src_bits;
+    }
+
+    src_line = src_bits;
+    dst_line = _scaled_bits;
+    for (i = 0; i < size->cy; i ++) {
+        const BYTE* test_line;
+        if (inter_line) {
+            memcpy (inter_line, src_line, pitch);
+            test_line = inter_line;
+        }
+        else {
+            test_line = src_line;
+        }
+
+        for (j = 0; j < size->cx; j++) {
+            dst_line [j*3+0] = test_line [(size->cx - j - 1)*3+0];
+            dst_line [j*3+1] = test_line [(size->cx - j - 1)*3+1];
+            dst_line [j*3+2] = test_line [(size->cx - j - 1)*3+2];
+        }
+
+        dst_line += pitch;
+        src_line += pitch;
+    }
+
+    return _scaled_bits;
+}
+
 static BYTE* _gdi_flip_bitmap_vert (BYTE* src_bits, const SIZE* size, int pitch)
 {
     BYTE* dst_line;
@@ -3790,6 +3836,12 @@ static BOOL _gdi_get_glyph_data (PDC pdc, Glyph32 glyph_value,
                 data = (BYTE*)(*devfont->font_ops->get_glyph_greybitmap) (logfont, devfont,
                         REAL_GLYPH(glyph_value), &pitch, &scale);
                 ctxt->cb = _dc_ft2subpixel_scan_line;
+
+                /* flip the subpixeled pixmap */
+                if (logfont->style & FS_FLIP_HORZ)
+                    data = _gdi_flip_subpixels_horz (data, bbox, pitch);
+                if (logfont->style & FS_FLIP_VERT)
+                    data = _gdi_flip_bitmap_vert (data, bbox, pitch);
             }
 #endif
             break;