<div dir="ltr"><div class="gmail_extra">Hi David<br><br><div class="gmail_quote">2013/3/9 David Herrmann <span dir="ltr"><<a href="mailto:dh.herrmann@gmail.com" target="_blank">dh.herrmann@gmail.com</a>></span><br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> Hi<br> <div class="im"><br> On Sat, Mar 9, 2013 at 8:41 AM, Chang Liu <<a href="mailto:cl91tp@gmail.com">cl91tp@gmail.com</a>> wrote:<br> > This patch fixes a rendering problem of certain CJK fonts which causes<br> > the rendered CJK characters to appear downward-shifted.<br> ><br> > For some CJK fonts, pango_layout_get_pixel_extent() returns different<br> > logical_rect for CJK glyphs and Latin glyphs. Therefore, using -rec.y<br> > as the y position of the baseline will render the CJK glyphs downward-<br> > shifted. face.baseline will be a better choice.<br> ><br> > ---<br> > src/font_pango.c | 2 +-<br> > 1 file changed, 1 insertion(+), 1 deletion(-)<br> ><br> > diff --git a/src/font_pango.c b/src/font_pango.c<br> > index c2954c6..0964123 100644<br> > --- a/src/font_pango.c<br> > +++ b/src/font_pango.c<br> > @@ -199,7 +199,7 @@ static int get_glyph(struct face *face, struct kmscon_glyph **out,<br> > bitmap.pixel_mode = FT_PIXEL_MODE_GRAY;<br> > bitmap.buffer = glyph->buf.data;<br> ><br> > - pango_ft2_render_layout_line(&bitmap, line, -rec.x, -rec.y);<br> > + pango_ft2_render_layout_line(&bitmap, line, -rec.x, face->baseline);<br> <br> </div>Ok, lets summarize how this is supposed to work (as I myself don't<br> remember it correctly):<br> We calculate the width/height of a cell by drawing the basic ASCII<br> characters in a cache and measuring them. Every other glyph is then<br> supposed to fit into multiples of these cells (multiples only in<br> horizontal direction).<br> "face->baseline" is set according to the baseline of this measurement<br> (that is, the ASCII characters).<br> <br> So what this basically does is calculating a bounding box for our<br> glyphs and computing the logical origin. Every glyph that we draw<br> should be drawn at the logical origin (which is face->baseline) and<br> clipped according to this box.<br> So we do have to use face->baseline here, indeed. Using -rec.y aligns<br> to the bottom edge instead, which is obviously wrong. </blockquote><div style>Yes, my thoughts exactly.</div><div style><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> Could you tell me the font-name so I can reproduce this?</blockquote><div style>For Latin languages I am using Lucida Console and for Chinese I am using</div><div style>Microsoft YaHei. Both of them are default fonts in MS Win 8 which I illegally ^_^<br> </div><div style>downloaded from the Internet. Not sure if you could do this in Europe but I guess</div><div style>you might need a valid license of Win 8 before you could legally use these fonts.</div><div style>However these fonts are available in Win 7 too and I don't think they underwent</div> <div style>substantial changes since then. Since most laptop came with a pre-installed Win 7</div><div style>I think you can legally copy these fonts from a Win 7 installation and use them</div><div style>for testing. They are located in C:\Windows\Fonts and named lucida.ttf and</div> <div style>msyh{,bd}.ttc.</div><div style><br></div><div style>There are also a bunch of CJK fonts in MS Win 7 which I tested. Look for .ttf or .ttc</div><div style>files which are larger than 1 MB, they are most certainly CJK fonts. They are rendered</div> <div style>correctly after the patch is applied.</div><div style><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> <br></blockquote><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> I changed your commit-message to mention why this fix is correct and<br> then applied the patch. I hope you don't mind.<br></blockquote><div style>No, not at all. </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> Commit: e874518153e509b74aa8e3e52b02642718eb5575<br></blockquote><div style><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> There's also ./docs/unicode-test.txt. Could you check whether there<br> are symbols in it that show this wrong behavior? If not, could you<br> tell me what symbols you used in your screenshots so I can add them.<br> <br></blockquote><div style>Yes. The 4th line (empty line included), the line with a `Unicode' in it, is Chinese</div><div style>for `What is Unicode?'. All the Chinese characters in that line show this behavior.</div> <div style> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> Thanks a lot for reporting this!<br> David<br> <div class="im"><br> > pthread_mutex_lock(&face->glyph_lock);<br> > ret = shl_hashtable_insert(face->glyphs, (void*)(long)id, glyph);<br> > --<br> > 1.8.1.5<br> ><br> </div>> _______________________________________________<br> > kmscon-devel mailing list<br> > <a href="mailto:kmscon-devel@lists.freedesktop.org">kmscon-devel@lists.freedesktop.org</a><br> > <a href="http://lists.freedesktop.org/mailman/listinfo/kmscon-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/kmscon-devel</a><br> </blockquote></div><br></div></div>