From a5e308972adf0ac7c5953152527da961707bd6b5 Mon Sep 17 00:00:00 2001
From: dooglus <dooglus@1f10aa63-cdf2-0310-b900-c93c546f37ac>
Date: Sat, 22 Nov 2008 15:40:51 +0000
Subject: [PATCH] Add Metaballs::hit_check() so metaballs can be selected by
 clicking on them.

git-svn-id: https://synfig.svn.sourceforge.net/svnroot/synfig@2252 1f10aa63-cdf2-0310-b900-c93c546f37ac
---
 .../trunk/src/modules/example/metaballs.cpp        | 24 ++++++++++++++++++++--
 synfig-core/trunk/src/modules/example/metaballs.h  |  4 ++++
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/synfig-core/trunk/src/modules/example/metaballs.cpp b/synfig-core/trunk/src/modules/example/metaballs.cpp
index 874d7f9..0cfa6c3 100644
--- a/synfig-core/trunk/src/modules/example/metaballs.cpp
+++ b/synfig-core/trunk/src/modules/example/metaballs.cpp
@@ -159,7 +159,27 @@ Metaballs::get_param_vocab()const
 	return ret;
 }
 
-static inline Real densityfunc(const synfig::Point &p, const synfig::Point &c, Real R)
+synfig::Layer::Handle
+Metaballs::hit_check(synfig::Context context, const synfig::Point &point)const
+{
+	Real density(totaldensity(point));
+
+	if (density <= 0 || density > 1 || get_amount() == 0)
+		return context.hit_check(point);
+
+	synfig::Layer::Handle tmp;
+
+	if (get_blend_method()==Color::BLEND_BEHIND && (tmp=context.hit_check(point)))
+		return tmp;
+
+	if (Color::is_onto(get_blend_method()) && !(context.hit_check(point)))
+		return 0;
+
+	return const_cast<Metaballs*>(this);
+}
+
+Real
+Metaballs::densityfunc(const synfig::Point &p, const synfig::Point &c, Real R)const
 {
 	const Real dx = p[0] - c[0];
 	const Real dy = p[1] - c[1];
@@ -179,7 +199,7 @@ static inline Real densityfunc(const synfig::Point &p, const synfig::Point &c, R
 }
 
 Real
-Metaballs::totaldensity(const Point &pos) const
+Metaballs::totaldensity(const Point &pos)const
 {
 	Real density = 0;
 
diff --git a/synfig-core/trunk/src/modules/example/metaballs.h b/synfig-core/trunk/src/modules/example/metaballs.h
index ee3bda5..d9ae649 100644
--- a/synfig-core/trunk/src/modules/example/metaballs.h
+++ b/synfig-core/trunk/src/modules/example/metaballs.h
@@ -55,6 +55,8 @@ private:
 
 	bool positive;
 
+	synfig::Real densityfunc(const synfig::Point &p, const synfig::Point &c, synfig::Real R)const;
+
 	synfig::Real totaldensity(const synfig::Point &pos)const;
 
 public:
@@ -70,6 +72,8 @@ public:
 	virtual bool accelerated_render(synfig::Context context,synfig::Surface *surface,int quality, const synfig::RendDesc &renddesc, synfig::ProgressCallback *cb)const;
 
 	virtual Vocab get_param_vocab()const;
+
+	virtual synfig::Layer::Handle hit_check(synfig::Context context, const synfig::Point &point)const;
 }; // END of class Metaballs
 
 /* === E N D =============================================================== */
-- 
2.7.4