vcl/inc/unx/cairotextrender.hxx | 8 +++++
vcl/unx/generic/gdi/cairotextrender.cxx | 50 +++++++++++++++++++++++++++-----
2 files changed, 51 insertions(+), 7 deletions(-)
New commits:
commit 35e4647689b1663a6e5a13f7ab8aebb0165e4ab2
Author: Caolán McNamara <caol...@redhat.com>
AuthorDate: Thu Aug 25 13:10:23 2022 +0100
Commit: Caolán McNamara <caol...@redhat.com>
CommitDate: Thu Aug 25 16:48:46 2022 +0200
tdf#150507 reenable slight hinting for cairo with
ResolutionIndependentLayout
it was disabled because of:
tdf#150145 text appears to have a row of pixels cropped out
which seems to be the same issue as
https://gitlab.freedesktop.org/cairo/cairo/-/issues/390
reenable, drop CAIRO_HINT_METRICS_OFF and emulate a proposed solution of
https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235 by
hacking in a route to disable CAIRO_ROUND_GLYPH_POS_ON
Change-Id: I3c9f982c9737b84fe0ee6b645f507e1226807d60
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/138810
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caol...@redhat.com>
diff --git a/vcl/inc/unx/cairotextrender.hxx b/vcl/inc/unx/cairotextrender.hxx
index c046b00c9e49..e9a85739827b 100644
--- a/vcl/inc/unx/cairotextrender.hxx
+++ b/vcl/inc/unx/cairotextrender.hxx
@@ -25,9 +25,15 @@
class GenericSalLayout;
class SalGraphics;
typedef struct _cairo cairo_t;
+typedef struct _cairo_font_options cairo_font_options_t;
class VCL_DLLPUBLIC CairoTextRender : public FreeTypeTextRenderImpl
{
+private:
+ // https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235
+ // I don't want to have CAIRO_ROUND_GLYPH_POS_ON set in the cairo
+ // surfaces font_options, but that's private, so tricky to achieve
+ cairo_font_options_t* mpRoundGlyphPosOffOptions;
protected:
virtual cairo_t* getCairoContext() = 0;
virtual void getSurfaceOffset(double& nDX, double& nDY) = 0;
@@ -37,6 +43,8 @@ protected:
public:
virtual void DrawTextLayout(const GenericSalLayout&, const
SalGraphics&) override;
+ CairoTextRender();
+ virtual ~CairoTextRender();
};
#endif
diff --git a/vcl/unx/generic/gdi/cairotextrender.cxx
b/vcl/unx/generic/gdi/cairotextrender.cxx
index 1e2e75c01d79..24e5580e9bdb 100644
--- a/vcl/unx/generic/gdi/cairotextrender.cxx
+++ b/vcl/unx/generic/gdi/cairotextrender.cxx
@@ -29,6 +29,11 @@
#include <cairo.h>
#include <cairo-ft.h>
+#if defined(CAIRO_HAS_SVG_SURFACE)
+#include <cairo-svg.h>
+#elif defined(CAIRO_HAS_PDF_SURFACE)
+#include <cairo-pdf.h>
+#endif
#include <deque>
@@ -125,6 +130,36 @@ extern "C"
}
#endif
+CairoTextRender::CairoTextRender()
+{
+ // https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235
+ // I don't want to have CAIRO_ROUND_GLYPH_POS_ON set in the cairo surfaces
+ // font_options when trying subpixel rendering, but that's a private
+ // feature of cairo_font_options_t, so tricky to achieve. Hack this by
+ // getting the font options of a backend known to set this private feature
+ // to CAIRO_ROUND_GLYPH_POS_OFF and then set to defaults the public
+ // features and the result can be merged with new font options to set
+ // CAIRO_ROUND_GLYPH_POS_OFF in those
+ mpRoundGlyphPosOffOptions = cairo_font_options_create();
+#if defined(CAIRO_HAS_SVG_SURFACE)
+ // svg, pdf and ps backends have CAIRO_ROUND_GLYPH_POS_OFF by default
+ cairo_surface_t* hack = cairo_svg_surface_create(nullptr, 1, 1);
+#elif defined(CAIRO_HAS_PDF_SURFACE)
+ cairo_surface_t* hack = cairo_pdf_surface_create(nullptr, 1, 1);
+#endif
+ cairo_surface_get_font_options(hack, mpRoundGlyphPosOffOptions);
+ cairo_surface_destroy(hack);
+ cairo_font_options_set_antialias(mpRoundGlyphPosOffOptions,
CAIRO_ANTIALIAS_DEFAULT);
+ cairo_font_options_set_subpixel_order(mpRoundGlyphPosOffOptions,
CAIRO_SUBPIXEL_ORDER_DEFAULT);
+ cairo_font_options_set_hint_style(mpRoundGlyphPosOffOptions,
CAIRO_HINT_STYLE_DEFAULT);
+ cairo_font_options_set_hint_metrics(mpRoundGlyphPosOffOptions,
CAIRO_HINT_METRICS_DEFAULT);
+}
+
+CairoTextRender::~CairoTextRender()
+{
+ cairo_font_options_destroy(mpRoundGlyphPosOffOptions);
+}
+
void CairoTextRender::DrawTextLayout(const GenericSalLayout& rLayout, const
SalGraphics& rGraphics)
{
const FreetypeFontInstance& rInstance =
static_cast<FreetypeFontInstance&>(rLayout.GetFont());
@@ -199,21 +234,22 @@ void CairoTextRender::DrawTextLayout(const
GenericSalLayout& rLayout, const SalG
if (pFontOptions || bDisableAA || bResolutionIndependentLayoutEnabled)
{
cairo_hint_style_t eHintStyle = pFontOptions ?
cairo_font_options_get_hint_style(pFontOptions) : CAIRO_HINT_STYLE_DEFAULT;
- cairo_hint_metrics_t eHintMetricsStyle = pFontOptions ?
cairo_font_options_get_hint_metrics(pFontOptions) : CAIRO_HINT_METRICS_DEFAULT;
- bool bAllowedHintStyle = !bResolutionIndependentLayoutEnabled ||
(eHintStyle == CAIRO_HINT_STYLE_NONE);
- bool bAllowedHintMetricStyle = !bResolutionIndependentLayoutEnabled ||
(eHintMetricsStyle == CAIRO_HINT_METRICS_OFF);
+ bool bAllowedHintStyle = !bResolutionIndependentLayoutEnabled ||
(eHintStyle == CAIRO_HINT_STYLE_NONE || eHintStyle == CAIRO_HINT_STYLE_SLIGHT);
- if (bDisableAA || !bAllowedHintStyle || !bAllowedHintMetricStyle)
+ if (bDisableAA || !bAllowedHintStyle ||
bResolutionIndependentLayoutEnabled)
{
// Disable font AA in case global AA setting is supposed to affect
// font rendering (not the default) and AA is disabled.
cairo_font_options_t* pOptions = pFontOptions ?
cairo_font_options_copy(pFontOptions) : cairo_font_options_create();
+
if (bDisableAA)
cairo_font_options_set_antialias(pOptions,
CAIRO_ANTIALIAS_NONE);
- if (!bAllowedHintMetricStyle)
- cairo_font_options_set_hint_metrics(pOptions,
CAIRO_HINT_METRICS_OFF);
if (!bAllowedHintStyle)
- cairo_font_options_set_hint_style(pOptions,
CAIRO_HINT_STYLE_NONE);
+ cairo_font_options_set_hint_style(pOptions,
CAIRO_HINT_STYLE_SLIGHT);
+ // Disable private CAIRO_ROUND_GLYPH_POS_ON by merging with font
options known to have
+ // CAIRO_ROUND_GLYPH_POS_OFF
+ if (bResolutionIndependentLayoutEnabled)
+ cairo_font_options_merge(pOptions, mpRoundGlyphPosOffOptions);
cairo_set_font_options(cr, pOptions);
cairo_font_options_destroy(pOptions);
}
