From 40e1b18877127d29970a19c95932ec60a3974e66 Mon Sep 17 00:00:00 2001 From: Paul Gideon Dann Date: Tue, 9 Aug 2016 15:02:53 +0100 Subject: [PATCH 3/4] Apply subpixel rendering in Cairo Backend Source: https://github.com/zhou13/poppler-subpixel/blob/master/poppler/poppler-subpixel.patch --- glib/demo/render.c | 25 ++++++++++++++++++++--- glib/poppler-page.cc | 10 ++++++++++ glib/poppler-page.h | 1 + poppler/CairoFontEngine.cc | 6 +++--- poppler/CairoOutputDev.cc | 24 ++++++++++++++++++++++ poppler/Gfx.cc | 41 ++++++++++++++++++++++++++++++++++++++ poppler/Gfx.h | 3 +++ poppler/Page.cc | 13 ++++++++++++ poppler/Page.h | 3 +++ 9 files changed, 120 insertions(+), 6 deletions(-) diff --git a/glib/demo/render.c b/glib/demo/render.c index 78d24bb5..d482ceb5 100644 --- a/glib/demo/render.c +++ b/glib/demo/render.c @@ -82,12 +82,14 @@ pgd_render_start (GtkButton *button, PgdRenderDemo *demo) { PopplerPage *page; + gboolean subpixel_rendering; gdouble page_width, page_height; gdouble width, height; gint x, y; gchar *str; GTimer *timer; cairo_t *cr; + cairo_font_options_t *fo; page = poppler_document_get_page (demo->doc, demo->page); if (!page) @@ -116,6 +118,21 @@ pgd_render_start (GtkButton *button, width, height); cr = cairo_create (demo->surface); + fo = cairo_font_options_create (); + cairo_get_font_options (cr, fo); + + subpixel_rendering = poppler_page_support_subpixel_rendering (page); + printf("subpixel_rendering %d\n", subpixel_rendering); + if (subpixel_rendering) { + cairo_set_source_rgb (cr, 1., 1., 1.); + cairo_paint (cr); + cairo_font_options_set_antialias (fo, CAIRO_ANTIALIAS_SUBPIXEL); + cairo_font_options_set_subpixel_order (fo, CAIRO_SUBPIXEL_ORDER_RGB); + } + + cairo_set_font_options (cr, fo); + cairo_font_options_destroy (fo); + cairo_save (cr); switch (demo->rotate) { case 90: @@ -143,9 +160,11 @@ pgd_render_start (GtkButton *button, poppler_page_render (page, cr); cairo_restore (cr); - cairo_set_operator (cr, CAIRO_OPERATOR_DEST_OVER); - cairo_set_source_rgb (cr, 1., 1., 1.); - cairo_paint (cr); + if (!subpixel_rendering) { + cairo_set_operator (cr, CAIRO_OPERATOR_DEST_OVER); + cairo_set_source_rgb (cr, 1., 1., 1.); + cairo_paint (cr); + } g_timer_stop (timer); diff --git a/glib/poppler-page.cc b/glib/poppler-page.cc index 8b5b4da0..709b760e 100644 --- a/glib/poppler-page.cc +++ b/glib/poppler-page.cc @@ -2447,3 +2447,13 @@ poppler_page_get_text_attributes_for_area (PopplerPage *page, return g_list_reverse(attributes); } + +gboolean +poppler_page_support_subpixel_rendering (PopplerPage *page) +{ + CairoOutputDev *output_dev; + g_return_val_if_fail (POPPLER_IS_PAGE (page), FALSE); + + output_dev = page->document->output_dev; + return page->page->supportSubpixelRendering(output_dev); +} diff --git a/glib/poppler-page.h b/glib/poppler-page.h index f99f0920..8ff914f4 100644 --- a/glib/poppler-page.h +++ b/glib/poppler-page.h @@ -147,6 +147,7 @@ void poppler_page_free_text_attributes (GList *li POPPLER_PUBLIC GList * poppler_page_get_text_attributes_for_area (PopplerPage *page, PopplerRectangle *area); +gboolean poppler_page_support_subpixel_rendering (PopplerPage *page); /* A rectangle on a page, with coordinates in PDF points. */ #define POPPLER_TYPE_RECTANGLE (poppler_rectangle_get_type ()) diff --git a/poppler/CairoFontEngine.cc b/poppler/CairoFontEngine.cc index bf6bd88d..d9e42304 100644 --- a/poppler/CairoFontEngine.cc +++ b/poppler/CairoFontEngine.cc @@ -124,7 +124,7 @@ CairoFont::getSubstitutionCorrection(GfxFont *gfxFont) cairo_matrix_t m; cairo_matrix_init_identity(&m); cairo_font_options_t *options = cairo_font_options_create(); - cairo_font_options_set_hint_style(options, CAIRO_HINT_STYLE_NONE); + cairo_font_options_set_hint_style(options, CAIRO_HINT_STYLE_SLIGHT); cairo_font_options_set_hint_metrics(options, CAIRO_HINT_METRICS_OFF); cairo_scaled_font_t *scaled_font = cairo_scaled_font_create(cairo_font_face, &m, &m, options); @@ -182,7 +182,7 @@ _ft_new_face_uncached (FT_Library lib, } font_face = cairo_ft_font_face_create_for_ft_face (face, - FT_LOAD_NO_HINTING | + FT_LOAD_TARGET_LIGHT | FT_LOAD_NO_BITMAP); if (cairo_font_face_set_user_data (font_face, &_ft_cairo_key, @@ -351,7 +351,7 @@ _ft_new_face (FT_Library lib, _ft_open_faces = l; l->font_face = cairo_ft_font_face_create_for_ft_face (tmpl.face, - FT_LOAD_NO_HINTING | + FT_LOAD_TARGET_LIGHT | FT_LOAD_NO_BITMAP); if (cairo_font_face_set_user_data (l->font_face, &_ft_cairo_key, diff --git a/poppler/CairoOutputDev.cc b/poppler/CairoOutputDev.cc index 68927636..c21229a7 100644 --- a/poppler/CairoOutputDev.cc +++ b/poppler/CairoOutputDev.cc @@ -205,6 +205,13 @@ void CairoOutputDev::setCairo(cairo_t *c) } if (c != nullptr) { cairo = cairo_reference (c); + { + cairo_font_options_t *options = cairo_font_options_create (); + cairo_get_font_options (cairo, options); + cairo_font_options_set_antialias (options, CAIRO_ANTIALIAS_SUBPIXEL); + cairo_set_font_options (cairo, options); + cairo_font_options_destroy (options); + } /* save the initial matrix so that we can use it for type3 fonts. */ //XXX: is this sufficient? could we miss changes to the matrix somehow? cairo_get_matrix(cairo, &orig_matrix); @@ -1431,6 +1438,7 @@ void CairoOutputDev::drawChar(GfxState *state, double x, double y, void CairoOutputDev::endString(GfxState *state) { int render; + GfxFontType fontType; if (!currentFont) return; @@ -1448,6 +1456,18 @@ void CairoOutputDev::endString(GfxState *state) goto finish; } + fontType = state->getFont()->getType(); + // Do not enable subpixel rendering for type3 font + // For some reason it does not work + if (fontType == fontType3) { + cairo_save(cairo); + cairo_font_options_t *fo; + fo = cairo_font_options_create (); + cairo_get_font_options (cairo, fo); + cairo_font_options_set_antialias (fo, CAIRO_ANTIALIAS_DEFAULT); + cairo_set_font_options (cairo, fo); + } + if (!(render & 1)) { LOG (printf ("fill string\n")); cairo_set_source (cairo, fill_pattern); @@ -1498,6 +1518,10 @@ void CairoOutputDev::endString(GfxState *state) } finish: + // pair with the previous cairo_save to disable subpixel rendering for type3 fonts + if (fontType == fontType3) { + cairo_restore(cairo); + } gfree (glyphs); glyphs = nullptr; if (use_show_text_glyphs) { diff --git a/poppler/Gfx.cc b/poppler/Gfx.cc index 47627ad3..d48a4b0c 100644 --- a/poppler/Gfx.cc +++ b/poppler/Gfx.cc @@ -4603,6 +4603,47 @@ void Gfx::doImage(Object *ref, Stream *str, bool inlineImg) { error(errSyntaxError, getPos(), "Bad image parameters"); } +bool Gfx::checkNormalBlendModeOnly(Object *str) { + printf("check blender mode start\n"); + Object args[maxArgs]; + int numArgs; + bool onlyNormalBlendMode; + Parser myParser(xref, str, false); + + numArgs = 0; + onlyNormalBlendMode = true; + + Object obj = myParser.getObj(); + while (!obj.isEOF()) { + if (obj.isCmd()) { + const char* cmd = obj.getCmd(); + + if (strcmp(cmd, "gs") == 0) { + GfxBlendMode mode; + Object obj1 = res->lookupGState(args[0].getName()); + if (!obj1.isNull()) { + Object obj2 = obj1.dictLookup("BM"); + if (!obj2.isNull()) { + if (state->parseBlendMode(&obj2, &mode)) { + printf("check blend mode: %d\n", mode); + onlyNormalBlendMode &= (mode == gfxBlendNormal); + } + } + } + } + + numArgs = 0; + } else if (numArgs < maxArgs) { + args[numArgs++] = obj.copy(); + } + + obj = myParser.getObj(); + } + + return onlyNormalBlendMode; +} + + bool Gfx::checkTransparencyGroup(Dict *resDict) { // check the effect of compositing objects as a group: // look for ExtGState entries with ca != 1 or CA != 1 or BM != normal diff --git a/poppler/Gfx.h b/poppler/Gfx.h index 19462e8d..b0bbd11c 100644 --- a/poppler/Gfx.h +++ b/poppler/Gfx.h @@ -192,6 +192,9 @@ public: // Get the current graphics state object. GfxState *getState() { return state; } + // Check whether a stream only contains normal blend mode (to enable subpixel rendering) + bool checkNormalBlendModeOnly(Object *str); + bool checkTransparencyGroup(Dict *resDict); void drawForm(Object *str, Dict *resDict, const double *matrix, const double *bbox, diff --git a/poppler/Page.cc b/poppler/Page.cc index d137ec4b..5950b964 100644 --- a/poppler/Page.cc +++ b/poppler/Page.cc @@ -336,6 +336,19 @@ Dict *Page::getResourceDictCopy(XRef *xrefA) { return dict ? dict->copy(xrefA) : nullptr; } +bool Page::supportSubpixelRendering(OutputDev *out) { + bool supported = false; + PDFRectangle box; + + Object obj = contents.fetch(xref); + if (!obj.isNull()) { + Gfx gfx(doc, out, attrs->getResourceDict(), &box, nullptr); + supported = gfx.checkNormalBlendModeOnly(&obj); + } + + return supported; +} + void Page::replaceXRef(XRef *xrefA) { Object obj1; Dict *pageDict = pageObj.getDict()->copy(xrefA); diff --git a/poppler/Page.h b/poppler/Page.h index 01f056f9..d6547a79 100644 --- a/poppler/Page.h +++ b/poppler/Page.h @@ -183,6 +183,9 @@ public: Object *getResourceDictObject(); Dict *getResourceDictCopy(XRef *xrefA); + // Whether the content in this page supports subpixel rendering (lcdfilter) + bool supportSubpixelRendering(OutputDev *out); + // Get annotations array. Object getAnnotsObject(XRef *xrefA = nullptr) { return annotsObj.fetch(xrefA ? xrefA : xref); } // Add a new annotation to the page -- 2.23.0