Integrated the motion blur in game and adjusted the parameters

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@9349 178a84e3-b1eb-0310-8ba1-8eac791a3b58

data/gui/options_video.stkgui

@@ -22,7 +22,7 @@
         <div width="75%" height="50" layout="horizontal-row" >
             <label I18N="In the graphics settings" text="Graphical Effects Level" align="center"/>
             <spacer width="20" height="20"/>
-            <gauge id="gfx_level" min_value="1" max_value="5" width="300" />
+            <gauge id="gfx_level" min_value="1" max_value="7" width="300" />
         </div>
         
         <spacer height="10" width="10"/>

data/shaders/motion_blur.frag

@@ -1,22 +1,50 @@
 // motion_blur.frag
 
-uniform float boost_amount;
+uniform float boost_amount;	// should be in the range [0.0, 1.0]
 uniform sampler2D color_buffer;
 
-#define BLUR_CENTER vec2(0.5, 0.3)
+// The blur direction points to the following center (we work in [0, 1]x[0, 1] coordinates):
-#define BLUR_SCALE 0.1
+#define BLUR_DIR_CENTER vec2(0.5, 0.7)
+
+// There is a mask around the character so that it doesn't get blurred
+#define BLUR_MASK_CENTER vec2(0.5, 0.2)
+#define BLUR_MASK_RADIUS 0.15
+
+// Final scaling factor
+#define BLUR_SCALE 0.2
+
+// Number of samples used for blurring
 #define NB_SAMPLES 12
 
 void main()
 {
 	vec2 texcoords = gl_TexCoord[0].st;
-	vec3 color = texture2D(color_buffer, texcoords);
-	vec2 blur_dir = -BLUR_SCALE * (texcoords - BLUR_CENTER);
 	
-	// Avoid blurring the top of the screen
+	// Sample the color buffer
-	float blur_factor = (1.0-texcoords.t);
+	vec3 color = texture2D(color_buffer, texcoords);
+	
+	// Compute the blur direction.
+	// IMPORTANT: we don't normalize it so that it avoids a glitch around BLUR_DIR_CENTER,
+	// plus it naturally scales the motion blur in a cool way :)
+	vec2 blur_dir = BLUR_DIR_CENTER - texcoords;
+	
+	// Compute the blurring factor:
+	// - apply the mask
+	float blur_factor = max(0.0, length(texcoords - BLUR_MASK_CENTER) - BLUR_MASK_RADIUS);
+	
+	// - avoid blurring the top of the screen
+	blur_factor *= (1.0-texcoords.t);
+	
+	// - apply the boost amount
+	blur_factor *= boost_amount;
+	
+	// - apply a final scaling factor
+	blur_factor *= BLUR_SCALE;
+	
+	// Scale the blur direction
 	blur_dir *= blur_factor;
 	
+	// Compute the blur
 	vec2 inc_vec = blur_dir / NB_SAMPLES;
 	vec2 blur_texcoords = texcoords + inc_vec;
 	for(int i=1 ; i < NB_SAMPLES ; i++)
@@ -25,6 +53,8 @@ void main()
 		blur_texcoords += inc_vec;
 	}
 	color /= NB_SAMPLES;
-	
 	gl_FragColor = vec4(color, 0.0);
+
+	// Keep this commented line for debugging:
+//	gl_FragColor = vec4(blur_factor, blur_factor, blur_factor, 0.0);
 }

src/config/user_config.hpp

@@ -387,9 +387,6 @@ namespace UserConfigParams
     /** True if hardware skinning should be enabled */
     PARAM_PREFIX bool                       m_hw_skinning_enabled  PARAM_DEFAULT( false );
 
-    /** True if post-processing effects should be enabled */
-    PARAM_PREFIX bool                       m_postprocess_enabled  PARAM_DEFAULT( false );
-
     // not saved to file
 
     // ---- Networking
@@ -437,6 +434,9 @@ namespace UserConfigParams
     PARAM_PREFIX BoolUserConfigParam         m_vsync
             PARAM_DEFAULT( BoolUserConfigParam(false, "vsync", &m_graphics_quality,
                                                "Whether vertical sync is enabled") );
+    PARAM_PREFIX BoolUserConfigParam         m_postprocess_enabled
+            PARAM_DEFAULT( BoolUserConfigParam(false, "postprocess_enabled", &m_graphics_quality,
+                                               "Whether post-processing (motion blur...) should be enabled") );
     
     // ---- Misc
     PARAM_PREFIX BoolUserConfigParam        m_minimal_race_gui

src/graphics/camera.cpp

@@ -443,6 +443,10 @@ void Camera::update(float dt)
         return;
     }
     
+    // Apply the motion blur according to the speed of the kart
+    if(UserConfigParams::m_postprocess_enabled)
+        irr_driver->getPostProcessing()->setCameraSpeed(m_kart->getCurrentMaxSpeed());
+
     positionCamera(dt, above_kart, cam_angle, side_way, distance, smoothing);
 }   // update
 

src/graphics/post_processing.cpp

@@ -21,13 +21,15 @@
 #include "irr_driver.hpp"
 #include "config/user_config.hpp"
 
+#define MOTION_BLUR_FACTOR (1.0f/15.0f)
+#define MOTION_BLUR_OFFSET 20.0f
+
 using namespace video;
 using namespace scene;
 
 PostProcessing::PostProcessing()
 {
     m_boost_amount = 0.0f;
-    //UserConfigParams::m_postprocess_enabled = true; // BOUM
 }
 
 PostProcessing::~PostProcessing()
@@ -122,6 +124,12 @@ void PostProcessing::render()
     video_driver->drawIndexedTriangleList(&vertices[0], 6, &indices[0], 2);
 }
 
+/** Set the boost amount according to the speed of the camera */
+void PostProcessing::setCameraSpeed(float cam_speed)
+{
+    m_boost_amount = core::clamp(MOTION_BLUR_FACTOR * (cam_speed - MOTION_BLUR_OFFSET), 0.0f, 1.0f);
+}
+
 /** Implement IShaderConstantsSetCallback. Shader constants setter for post-processing */
 void PostProcessing::OnSetConstants(video::IMaterialRendererServices *services, s32 user_data)
 {

src/graphics/post_processing.hpp

@@ -54,8 +54,8 @@ public:
     /** Is the hardware able to use post-processing? */
     inline bool     isSupported() const                 {return m_supported;}
     
-    /** Boost amount, used to tune the motion blur. Must be in the range 0.0 to 1.0 */
+    /** Set the boost amount according to the speed of the camera */
-    inline void     setBoostAmount(float boost_amount)  {m_boost_amount = boost_amount;}
+    void            setCameraSpeed(float cam_speed);
     
     /** Implement IShaderConstantsSetCallback. Shader constants setter for post-processing */
     virtual void    OnSetConstants(video::IMaterialRendererServices *services, s32 user_data);

src/karts/max_speed.cpp

@@ -159,7 +159,7 @@ float MaxSpeed::getSpeedIncreaseTimeLeft(unsigned int category)
 void MaxSpeed::update(float dt)
 {
 
-    // First comput the minimum max-speed fraction, which 
+    // First compute the minimum max-speed fraction, which 
     // determines the overall decrease of maximum speed.
     // ---------------------------------------------------
     float f = 1.0f;

src/states_screens/options_screen_video.cpp

@@ -44,11 +44,12 @@ using namespace GUIEngine;
 DEFINE_SCREEN_SINGLETON( OptionsScreenVideo );
 
 // Look-up table for GFX levels
-const bool GFX           [] = {false, true,  true,  true,  true,  true};
+const bool GFX                [] = {false, true,  true,  true,  true,  true,  true};
-const int  GFX_ANIM_KARTS[] = {0,     0,     1,     2,     2,     2   };
+const int  GFX_ANIM_KARTS     [] = {0,     0,     1,     2,     2,     2,     2};
-const bool GFX_WEATHER   [] = {false, false, false, false, true,  true};
+const bool GFX_WEATHER        [] = {false, false, false, false, true,  true,  true};
-const bool GFX_ANTIALIAS [] = {false, false, false, false, false, true};
+const bool GFX_ANTIALIAS      [] = {false, false, false, false, false, true,  true};
-const int  GFX_LEVEL_AMOUNT = 6;
+const bool GFX_POSTPROCESSING [] = {false, false, false, false, false, false, true};
+const int  GFX_LEVEL_AMOUNT = 7;
 
 // -----------------------------------------------------------------------------
 
@@ -252,7 +253,8 @@ void OptionsScreenVideo::init()
         if (UserConfigParams::m_show_steering_animations == GFX_ANIM_KARTS[l] &&
             UserConfigParams::m_graphical_effects        == GFX[l] &&
             UserConfigParams::m_weather_effects          == GFX_WEATHER[l] &&
-            UserConfigParams::m_fullscreen_antialiasing  == GFX_ANTIALIAS[l])
+            UserConfigParams::m_fullscreen_antialiasing  == GFX_ANTIALIAS[l] &&
+            UserConfigParams::m_postprocess_enabled      == GFX_POSTPROCESSING[l])
         {
             gfx->setValue(l+1);
             break;
@@ -303,6 +305,8 @@ void OptionsScreenVideo::updateTooltip()
                                   (UserConfigParams::m_show_steering_animations == 1 ? me : none));
     //I18N: in graphical options
     tooltip = tooltip + L"\n" + _("Anti-aliasing (requires restart) : %s", UserConfigParams::m_fullscreen_antialiasing ? enabled : disabled);
+    //I18N: in graphical options
+    tooltip = tooltip + L"\n" + _("Post-processing (motion blur) : %s", UserConfigParams::m_postprocess_enabled ? enabled : disabled);
     gfx->setTooltip(tooltip);
 }
 
@@ -357,6 +361,7 @@ void OptionsScreenVideo::eventCallback(Widget* widget, const std::string& name,
         UserConfigParams::m_graphical_effects        = GFX[level-1];
         UserConfigParams::m_weather_effects          = GFX_WEATHER[level-1];
         UserConfigParams::m_fullscreen_antialiasing  = GFX_ANTIALIAS[level-1];
+        UserConfigParams::m_postprocess_enabled      = GFX_POSTPROCESSING[level-1];
         
         updateTooltip();
     }