Demonstrating the new particles : fire effect in crecent crossing

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@7597 178a84e3-b1eb-0310-8ba1-8eac791a3b58

data/gfx/fire.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0"?>
+<particles emitter="point">
+
+    <spreading angle="24"      />
+    
+    <velocity  x="0.000"
+               y="0.005"
+               z="0.000"         />
+    
+    <material  file="explode.png"  />
+    
+    <!-- Amount of particles emitted per second -->
+    <rate      min="30"
+               max="50"         />
+    
+    <!-- Minimal and maximal lifetime of a particle, in milliseconds. -->
+    <lifetime  min="300"
+               max="500"         />
+    
+    <!-- Size of the particles -->
+    <size      min="0.6"
+               max="0.8"        />
+    
+    <color     min="255 255 255"
+               max="255 255 255" />
+
+  <fadeout time="300" />
+
+</particles>

src/tracks/track.cpp

@@ -843,6 +843,10 @@ void Track::loadTrackModel(World* parent, unsigned int mode_id)
             try
             {
                 ParticleKind* kind = ParticleKindManager::get()->getParticles( path.c_str() );
+                if (kind == NULL)
+                {
+                    throw std::runtime_error(path + " could not be loaded");
+                }
                 ParticleEmitter* emitter = new ParticleEmitter( kind, emitter_origin );
                 m_all_emitters.push_back(emitter);
             }