cache cairo_pattern_t's for PixFader so that we don't generate one per fader, but rather one per size+color combination

git-svn-id: svn://localhost/ardour2/branches/3.0@13874 d708f5d6-7413-0410-9779-e7cbd77b26cf

2 files changed, 65 insertions, 16 deletions

diff --git a/libs/gtkmm2ext/gtkmm2ext/pixfader.h b/libs/gtkmm2ext/gtkmm2ext/pixfader.h
index 039a822bcd..1e1a76d744 100644
--- a/libs/gtkmm2ext/gtkmm2ext/pixfader.h
+++ b/libs/gtkmm2ext/gtkmm2ext/pixfader.h
@@ -70,9 +70,52 @@ class PixFader : public Gtk::DrawingArea
   private:
 	int span, girth;
 	int _orien;
+        cairo_pattern_t* pattern;
+
+        struct FaderImage {
+	    cairo_pattern_t* pattern;
+	    double fr;
+	    double fg;
+	    double fb;
+	    double br;
+	    double bg;
+	    double bb;
+	    int width;
+	    int height;
+
+	    FaderImage (cairo_pattern_t* p, 
+			double afr, double afg, double afb, 
+			double abr, double abg, double abb,
+			int w, int h) 
+		    : pattern (p)
+		    , fr (afr)
+		    , fg (afg)
+		    , fb (afb)
+		    , br (abr)
+		    , bg (abg)
+		    , bb (abb)
+		    , width (w)
+		    , height (h)
+	    {}
+
+	    bool matches (double afr, double afg, double afb, 
+			  double abr, double abg, double abb,
+			  int w, int h) {
+		    return width == w && 
+			    height == h &&
+			    afr == fr &&
+			    afg == fg && 
+			    afb == fb &&
+			    abr == br &&
+			    abg == bg && 
+			    abb == bb;
+	    }
+	};
 
-	cairo_pattern_t* pattern;
-	cairo_pattern_t* texture_pattern;
+        static std::list<FaderImage*> _patterns;
+        static cairo_pattern_t* find_pattern (double afr, double afg, double afb, 
+					      double abr, double abg, double abb, 
+					      int w, int h);
 
 	bool _hovering;
 
@@ -88,7 +131,6 @@ class PixFader : public Gtk::DrawingArea
 	int display_span ();
 	void set_adjustment_from_event (GdkEventButton *);
 	void update_unity_position ();
-        void free_patterns ();
 	void create_patterns();
 };
 
diff --git a/libs/gtkmm2ext/pixfader.cc b/libs/gtkmm2ext/pixfader.cc
index 43657a5902..994c719cd3 100644
--- a/libs/gtkmm2ext/pixfader.cc
+++ b/libs/gtkmm2ext/pixfader.cc
@@ -33,13 +33,14 @@ using namespace std;
 #define CORNER_RADIUS 4
 #define FADER_RESERVE (2*CORNER_RADIUS)
 
+std::list<PixFader::FaderImage*> PixFader::_patterns;
+
 PixFader::PixFader (Gtk::Adjustment& adj, int orientation, int fader_length, int fader_girth)
 	: adjustment (adj)
 	, span (fader_length)
 	, girth (fader_girth)
 	, _orien (orientation)
 	, pattern (0)
-	, texture_pattern (0)
 	, _hovering (false)
 	, last_drawn (-1)
 	, dragging (false)
@@ -55,27 +56,24 @@ PixFader::PixFader (Gtk::Adjustment& adj, int orientation, int fader_length, int
 
 PixFader::~PixFader ()
 {
-	free_patterns ();
 }
 
-void
-PixFader::free_patterns ()
+cairo_pattern_t*
+PixFader::find_pattern (double afr, double afg, double afb, 
+			double abr, double abg, double abb, 
+			int w, int h)
 {
-	if (pattern) {
-		cairo_pattern_destroy (pattern);
-		pattern = 0;
-	}
-	if (texture_pattern) {
-		cairo_pattern_destroy (texture_pattern);
-		texture_pattern = 0;
+	for (list<FaderImage*>::iterator f = _patterns.begin(); f != _patterns.end(); ++f) {
+		if ((*f)->matches (afr, afg, afb, abr, abg, abb, w, h)) {
+			return (*f)->pattern;
+		}
 	}
+	return 0;
 }
 
 void
 PixFader::create_patterns ()
 {
-	free_patterns ();
-
 	Gdk::Color c = get_style()->get_fg (get_state());
 	float fr, fg, fb;
 	float br, bg, bb;
@@ -96,6 +94,11 @@ PixFader::create_patterns ()
 
 	double w = get_width();
 
+	if ((pattern = find_pattern (fr, fg, fb, br, bg, bb, get_width(), get_height())) != 0) {
+		/* found it - use it */
+		return;
+	}
+
  	if (_orien == VERT) {
 		
 		surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, get_width(), get_height() * 2.0);
@@ -154,6 +157,10 @@ PixFader::create_patterns ()
 		pattern = cairo_pattern_create_for_surface (surface);
 	}
 
+	/* cache it for others to use */
+
+	_patterns.push_back (new FaderImage (pattern, fr, fg, fb, br, bg, bb, get_width(), get_height()));
+
 	cairo_destroy (tc);
 	cairo_surface_destroy (surface);