On 25.06.21 15:04, David Kastrup wrote:
Well, the PostScript code sucks for a reason. It goes to tremendous
effort to make stems in bitmaps end up more consistent in thickness than
rendering left and right edge independently would.
Yes. But I havn't had a look at the 'strokeadjust with cairo' topic.
For those who are interested: The aattached patch adds uri hyperlinks and
internal page hyperlinks (forward references to page numbers have a problem).
Also included: partial ellipses, needed by the woodwind diagram code.
Knut
>From b38e3023e3d2cf15362a03605808b10d2f866488 Mon Sep 17 00:00:00 2001
From: Knut Petersen <knup...@gmail.com>
Date: Fri, 25 Jun 2021 21:45:00 +0200
Subject: [PATCH] CAIRO: Add 1) uri and internal hyperlinks 2) partial ellipses
Internal page hyperlinks to pages that have not been generated
seem to be broken ... a cairo bug or a problem of the documentation?
Partial ellipses are needed by the woodwind diagram code.
Still some features are missing ...
---
lily/cairo.cc | 115 ++++++++++++++++++++++++++++++++++++++++------
scm/output-ps.scm | 3 ++
2 files changed, 103 insertions(+), 15 deletions(-)
diff --git a/lily/cairo.cc b/lily/cairo.cc
index 216b7ea4d4..c5efa6af74 100644
--- a/lily/cairo.cc
+++ b/lily/cairo.cc
@@ -676,7 +676,7 @@ LY_DEFINE(ly_cairo_draw_circle, "ly:cairo-draw-circle",
LY_DEFINE(ly_cairo_draw_ellipse, "ly:cairo-draw-ellipse",
4, 0, 0, (SCM xradius, SCM yradius, SCM thickness, SCM filled),
- "CAIRO: equivalent of our postscript procedure draw_circle.")
+ "CAIRO: equivalent of our postscript procedure draw_ellipse.")
{
if (!from_scm<bool> (ly_get_option (ly_symbol2scm ("cairotest"))))
return SCM_UNSPECIFIED;
@@ -684,10 +684,10 @@ LY_DEFINE(ly_cairo_draw_ellipse, "ly:cairo-draw-ellipse",
LY_ASSERT_TYPE (scm_is_real, yradius, 2);
LY_ASSERT_TYPE (scm_is_real, thickness, 3);
LY_ASSERT_TYPE (scm_is_bool, filled, 4);
- bool fill = from_scm<bool> (filled);
double xrad = from_scm<Real> (xradius);
double yrad = from_scm<Real> (yradius);
double blot = from_scm<Real> (thickness);
+ bool fill = from_scm<bool> (filled);
double cx, cy;
cairo_save(cr);
cairo_get_current_point(cr,&cx, &cy);
@@ -707,6 +707,47 @@ LY_DEFINE(ly_cairo_draw_ellipse, "ly:cairo-draw-ellipse",
+LY_DEFINE(ly_cairo_draw_partial_ellipse, "ly:cairo-draw-partial-ellipse",
+ 7, 0, 0, (SCM xradius, SCM yradius, SCM startangle, SCM endangle, SCM thickness, SCM connected, SCM filled),
+ "CAIRO: equivalent of our postscript procedure draw_partial_ellipse.")
+{
+ if (!from_scm<bool> (ly_get_option (ly_symbol2scm ("cairotest"))))
+ return SCM_UNSPECIFIED;
+ LY_ASSERT_TYPE (scm_is_real, xradius, 1);
+ LY_ASSERT_TYPE (scm_is_real, yradius, 2);
+ LY_ASSERT_TYPE (scm_is_real, startangle, 3);
+ LY_ASSERT_TYPE (scm_is_real, endangle, 4);
+ LY_ASSERT_TYPE (scm_is_real, thickness, 5);
+ LY_ASSERT_TYPE (scm_is_bool, connected, 6);
+ LY_ASSERT_TYPE (scm_is_bool, filled, 7);
+ double xrad = from_scm<Real> (xradius);
+ double yrad = from_scm<Real> (yradius);
+ double sang = from_scm<Real> (startangle);
+ double eang = from_scm<Real> (endangle);
+ double blot = from_scm<Real> (thickness);
+ bool conn = from_scm<bool> (connected);
+ bool fill = from_scm<bool> (filled);
+ double cx, cy;
+ cairo_save(cr);
+ cairo_get_current_point(cr,&cx, &cy);
+ cairo_translate(cr,cx,cy);
+ cairo_scale(cr,1,yrad/xrad);
+ cairo_new_path(cr);
+ cairo_arc(cr,0,0,xrad*sf,-eang/180*M_PI,-sang/180*M_PI);
+ if (conn)
+ cairo_close_path(cr);
+ cairo_restore(cr);
+ cairo_set_line_width(cr,blot*sf);
+ if (fill) {
+ cairo_stroke_preserve(cr);
+ cairo_fill(cr);
+ } else
+ cairo_stroke(cr);
+ return SCM_UNSPECIFIED;
+}
+
+
+
LY_DEFINE(ly_cairo_set_rotation, "ly:cairo-set-rotation",
3, 0, 0, (SCM angle, SCM varx, SCM vary),
"CAIRO: equivalent of setrotation.")
@@ -748,6 +789,63 @@ LY_DEFINE(ly_cairo_reset_rotation, "ly:cairo-reset-rotation",
+LY_DEFINE(ly_cairo_url_link, "ly:cairo-url-link",
+ 3, 0, 0, (SCM target, SCM varx, SCM vary),
+ "CAIRO: Add an URL link.")
+{
+ if (!from_scm<bool> (ly_get_option (ly_symbol2scm ("cairotest"))))
+ return SCM_UNSPECIFIED;
+ LY_ASSERT_TYPE (scm_is_string, target, 1);
+ LY_ASSERT_TYPE (scm_is_pair, varx, 2);
+ LY_ASSERT_TYPE (scm_is_pair, vary, 3);
+ string url = ly_scm2string (target);
+ double x = from_scm<Real>(scm_car (varx));
+ double y = from_scm<Real>(scm_car (vary));
+ double w = from_scm<Real>(scm_cdr (varx)) - x;
+ double h = y - from_scm<Real>(scm_cdr (vary));
+ double cx, cy;
+ cairo_get_current_point(cr,&cx, &cy);
+ string attr = "rect=[ " + std::to_string (cx + x*sf) + " " + std::to_string (cy - y*sf) + " "
+ + std::to_string (w*sf) + " " + std::to_string (h*sf) + " ] uri='" + url + "'";
+ cairo_tag_begin (cr, CAIRO_TAG_LINK, attr.c_str());
+ cairo_tag_end (cr, CAIRO_TAG_LINK);
+ debug_output(_f("url-link %s",attr.c_str()));
+ return SCM_UNSPECIFIED;
+}
+
+
+
+// FIXME Links to pages that already have been generated work fine,
+// links with forward references do _not_ work in cairo 1.16.
+// This is either a documentation flaw or a cairo bug. Maybe a named
+// destination can be used? I'll have to investigate that.
+//
+LY_DEFINE(ly_cairo_page_link, "ly:cairo-page-link",
+ 3, 0, 0, (SCM target, SCM varx, SCM vary),
+ "CAIRO: Add a page link.")
+{
+ if (!from_scm<bool> (ly_get_option (ly_symbol2scm ("cairotest"))))
+ return SCM_UNSPECIFIED;
+ LY_ASSERT_TYPE (scm_is_integer, target, 1);
+ LY_ASSERT_TYPE (scm_is_pair, varx, 2);
+ LY_ASSERT_TYPE (scm_is_pair, vary, 3);
+ int page = from_scm<int>(target);
+ double x = from_scm<Real>(scm_car (varx));
+ double y = from_scm<Real>(scm_car (vary));
+ double w = from_scm<Real>(scm_cdr (varx)) - x;
+ double h = y - from_scm<Real>(scm_cdr (vary));
+ double cx, cy;
+ cairo_get_current_point(cr,&cx, &cy);
+ string attr = "rect=[ " + std::to_string (cx + x*sf) + " " + std::to_string (cy - y*sf) + " "
+ + std::to_string (w*sf) + " " + std::to_string (h*sf) + " ] page=" + std::to_string (page) + " pos=[0.0 0.0]";
+ cairo_tag_begin (cr, CAIRO_TAG_LINK, attr.c_str());
+ cairo_tag_end (cr, CAIRO_TAG_LINK);
+ message(_f("page-link %s",attr.c_str()));
+ return SCM_UNSPECIFIED;
+}
+
+
+
LY_DEFINE(ly_cairo_at_eof, "ly:cairo-at-eof",
0, 0, 0, (),
"CAIRO: Inform cairo to finalize the pdf and to clean up.")
@@ -759,16 +857,3 @@ LY_DEFINE(ly_cairo_at_eof, "ly:cairo-at-eof",
debug_output(_f("CAIRO: Finished Pdf, cairo surface and context destroyed."));
return SCM_UNSPECIFIED;
}
-
-
-
-//
-//
-// still missing: music-drawing-routines.ps: /draw_partial_ellipse % filled connect x-radius y-radius startangle endangle thickness draw_partial_ellipse
-// music-drawing-routines.ps: /mark_URI% llx lly urx ury URI
-// music-drawing-routines.ps: /mark_page_link % llx lly urx ury page
-// music-drawing-routines.ps: /draw_dashed_line % dx dy thickness dashpattern offset draw_dashed_line
-//
-// lots of other things ... rotation, transformations, ... transparency, ... etc, etc
-//
-//
diff --git a/scm/output-ps.scm b/scm/output-ps.scm
index 09ebf66997..c8730326c6 100644
--- a/scm/output-ps.scm
+++ b/scm/output-ps.scm
@@ -67,6 +67,7 @@
x1 y1 thick))
(define (partial-ellipse x-radius y-radius start-angle end-angle thick connect fill)
+ (ly:cairo-draw-partial-ellipse x-radius y-radius start-angle end-angle thick connect fill)
(ly:format "~a ~a ~4f ~4f ~4f ~4f ~4f draw_partial_ellipse\n"
(if fill "true" "false")
(if connect "true" "false")
@@ -239,6 +240,7 @@
"unknown\n")
(define (url-link url x y)
+ (ly:cairo-url-link url x y)
(ly:format "~a ~a currentpoint vector_add ~a ~a currentpoint vector_add (~a) mark_URI\n"
(car x)
(car y)
@@ -247,6 +249,7 @@
url))
(define (page-link page-no x y)
+ (ly:cairo-page-link page-no x y)
(if (number? page-no)
(ly:format "~a ~a currentpoint vector_add ~a ~a currentpoint vector_add ~a mark_page_link\n"
(car x)
--
2.31.1
