Make grass speed and amplitude configurable

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@12735 178a84e3-b1eb-0310-8ba1-8eac791a3b58

data/shaders/grass.vert

@@ -1,4 +1,5 @@
 uniform float angle;
+uniform float amplitude;
 varying vec4 coord;
 
 
@@ -6,7 +7,7 @@ void main()
 {
 	gl_TexCoord[0] =  gl_MultiTexCoord0;
 	vec4 vertexPosition = ftransform(); //gl_ModelViewMatrix *  gl_Vertex;
-	vertexPosition += vec4(1,1,0,0) * 0.25 * gl_Color.r * sin(angle);
+	vertexPosition += vec4(1,1,0,0) * amplitude * gl_Color.r * sin(angle);
 	gl_Position = vertexPosition;
 	gl_FrontColor = vec4(1,1,1,1);
 	gl_BackColor = vec4(1,1,1,1);

src/graphics/material.cpp

@@ -174,26 +174,31 @@ class GrassShaderProvider : public video::IShaderConstantSetCallBack
 {    
     bool m_fog;
     float m_angle;
+    float m_amplitude;
+    float m_speed;
     
 public:
     LEAK_CHECK()
     
+        
+    GrassShaderProvider(float amplitude, float speed)
+    {
+        m_fog = false;
+        m_angle = 0.0f;
+        m_amplitude = amplitude;
+        m_speed = speed;
+    }
+    
+    
     void enableFog(bool enable)
     {
         m_fog = enable;
     }
     
-    
-    GrassShaderProvider()
-    {
-        m_fog = false;
-        m_angle = 0.0f;
-    }
-    
     virtual void OnSetConstants(irr::video::IMaterialRendererServices *services,
                                 s32 userData)
     {
-        m_angle += GUIEngine::getLatestDt()*0.4f;
+        m_angle += GUIEngine::getLatestDt()*m_speed;
         if (m_angle > M_PI*2) m_angle -= M_PI*2;
         services->setVertexShaderConstant("angle", &m_angle, 1);
         
@@ -203,6 +208,8 @@ public:
         s32 tex = 0;
         services->setVertexShaderConstant("tex", &tex, 1);
         
+        services->setVertexShaderConstant("amplitude", &m_amplitude, 1);
+        
         if (m_fog)
         {
             Track* t = World::getWorld()->getTrack();
@@ -531,6 +538,10 @@ Material::Material(const XMLNode *node, int index, bool deprecated)
     else if (s == "grass")
     {
         m_graphical_effect = GE_GRASS;
+        m_grass_speed = 0.4f;
+        m_grass_amplitude = 0.25f;
+        node->get("grass-speed", &m_grass_speed);
+        node->get("grass-amplitude", &m_grass_amplitude);
     }
     else if (s == "none")
     {
@@ -1292,7 +1303,7 @@ void  Material::setMaterialProperties(video::SMaterial *m, scene::IMeshBuffer* m
         {
             if (m_shaders[GRASS_SHADER] == NULL)
             {
-                m_shaders[GRASS_SHADER] = new GrassShaderProvider();
+                m_shaders[GRASS_SHADER] = new GrassShaderProvider(m_grass_speed, m_grass_amplitude);
             }
             
             bool fog = World::getWorld()->getTrack()->isFogEnabled();

src/graphics/material.hpp

@@ -131,6 +131,9 @@ private:
     /** Particles to show on touch */
     std::string      m_collision_particles;
     
+    float            m_grass_speed;
+    float            m_grass_amplitude;
+    
     /** If the property should be ignored in the physics. Example would be
      *  plants that a kart can just drive through. */
     bool             m_ignore;