Added support for external masks; this allows using JPEG even on images that need transparency. Reduced palmacacia from 800 KB to 300 KB using this feature

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@8064 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/graphics/irr_driver.cpp

@@ -863,6 +863,43 @@ video::ITexture *IrrDriver::getTexture(const std::string &filename,
     return out;
 }   // getTexture
 
+// ----------------------------------------------------------------------------
+
+ITexture* IrrDriver::applyMask(video::ITexture* texture, const std::string& mask_path)
+{
+    video::IImage* img = 
+        m_scene_manager->getVideoDriver()->createImage(texture, core::position2d<s32>(0,0), texture->getSize());
+
+    video::IImage* mask = 
+        m_scene_manager->getVideoDriver()->createImageFromFile(mask_path.c_str());
+    
+    if (img == NULL || mask == NULL) return NULL;
+    
+    if (img->lock() && mask->lock())
+    {
+        core::dimension2d<u32> dim = img->getDimension();
+        for (unsigned int x = 0; x < dim.Width; x++)
+        {
+            for (unsigned int y = 0; y < dim.Height; y++)
+            {
+                video::SColor col = img->getPixel(x, y);
+                video::SColor alpha = mask->getPixel(x, y);
+                col.setAlpha( alpha.getRed() );
+                img->setPixel(x, y, col, false);
+            }   // for y
+        }   // for x
+        
+        mask->unlock();
+        img->unlock();
+    }
+    else
+    {
+        return NULL;
+    }
+    
+    return m_scene_manager->getVideoDriver()->addTexture(texture->getName().getPath().c_str(), img, NULL);  
+}
+
 // ----------------------------------------------------------------------------
 /** Sets the ambient light.
  *  \param light The colour of the light to set.

src/graphics/irr_driver.hpp

@@ -105,6 +105,8 @@ public:
     gui::IGUIEnvironment *getGUI() const { return m_gui_env; }
     //irr::gui::IGUIFont   *getRaceFont() const { return m_race_font; }
     
+    video::ITexture* IrrDriver::applyMask(video::ITexture* texture, const std::string& mask_path);
+    
     void                  displayFPS();
     /** this is not really used to process events, it's only used to shut down irrLicht's
       * chatty logging until the event handler is ready to take the task

src/graphics/material.cpp

@@ -89,6 +89,8 @@ Material::Material(const XMLNode *node, int index)
     node->get("backface-culling", &m_backface_culling  );
     node->get("disable-z-write",  &m_disable_z_write   );
 
+    node->get("mask",             &m_mask);
+    
     if (node->get("normal-map",  &m_normal_map_tex))
     {
         m_normal_map = true;
@@ -158,7 +160,6 @@ Material::Material(const XMLNode *node, int index)
         
         if (child_node->getName() == "sfx")
         {
-          
             initCustomSFX(child_node);
         }
         else if (child_node->getName() == "particles")
@@ -393,6 +394,12 @@ void  Material::setMaterialProperties(video::SMaterial *m) const
 {
     int modes = 0;
     
+    if (m_mask.size() > 0)
+    {
+        video::ITexture* newtex = irr_driver->applyMask(m->getTexture(0), m_mask);
+        if (newtex) m->setTexture(0, newtex);
+    }
+    
     if (m_alpha_testing)
     {
         // Note: if EMT_TRANSPARENT_ALPHA_CHANNEL is used, you have to use

src/graphics/material.hpp

@@ -142,6 +142,8 @@ private:
      *  is <0 the kart specific value will be used. */
     float            m_zipper_fade_out_time;
 
+    std::string      m_mask;
+    
     void  init    (unsigned int index);
     void  install (bool is_full_path=false);
     void  initCustomSFX(const XMLNode *sfx);