Merge pull request #1469 from drummyfish/master

water shader improvements (partially fixes #3365)

apps/openmw/mwrender/renderingmanager.cpp

@@ -279,11 +279,14 @@ namespace MWRender
         mViewDistance = Settings::Manager::getFloat("viewing distance", "Camera");
         mFieldOfView = Settings::Manager::getFloat("field of view", "Camera");
         mFirstPersonFieldOfView = Settings::Manager::getFloat("first person field of view", "Camera");
-        updateProjectionMatrix();
         mStateUpdater->setFogEnd(mViewDistance);
 
         mRootNode->getOrCreateStateSet()->addUniform(new osg::Uniform("near", mNearClip));
         mRootNode->getOrCreateStateSet()->addUniform(new osg::Uniform("far", mViewDistance));
+
+        mUniformNear = mRootNode->getOrCreateStateSet()->getUniform("near");
+        mUniformFar = mRootNode->getOrCreateStateSet()->getUniform("far");
+        updateProjectionMatrix();
     }
 
     RenderingManager::~RenderingManager()
@@ -889,6 +892,9 @@ namespace MWRender
         if (mFieldOfViewOverridden)
             fov = mFieldOfViewOverride;
         mViewer->getCamera()->setProjectionMatrixAsPerspective(fov, aspect, mNearClip, mViewDistance);
+
+        mUniformNear->set(mNearClip);
+        mUniformFar->set(mViewDistance);
     }
 
     void RenderingManager::updateTextureFiltering()

apps/openmw/mwrender/renderingmanager.hpp

@@ -83,6 +83,9 @@ namespace MWRender
         SceneUtil::UnrefQueue* getUnrefQueue();
         Terrain::World* getTerrain();
 
+        osg::Uniform* mUniformNear;
+        osg::Uniform* mUniformFar;
+
         void preloadCommonAssets();
 
         double getReferenceTime() const;

apps/openmw/mwrender/water.cpp

@@ -336,8 +336,7 @@ public:
 
     void setWaterLevel(float waterLevel)
     {
-        setViewMatrix(osg::Matrix::translate(0,0,-waterLevel) * osg::Matrix::scale(1,1,-1) * osg::Matrix::translate(0,0,waterLevel));
+        setViewMatrix(osg::Matrix::scale(1,1,-1) * osg::Matrix::translate(0,0,2 * waterLevel));
-
         mClipCullNode->setPlane(osg::Plane(osg::Vec3d(0,0,1), osg::Vec3d(0,0,waterLevel)));
     }
 

files/shaders/water_fragment.glsl

@@ -6,7 +6,7 @@
 
 // tweakables -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
-const float VISIBILITY = 1200.0; // how far you can look through water
+const float VISIBILITY = 2.5;
 
 const float BIG_WAVES_X = 0.1; // strength of big waves
 const float BIG_WAVES_Y = 0.1;
@@ -31,6 +31,8 @@ const vec3 SUN_EXT = vec3(0.45, 0.55, 0.68);       //sunlight extinction
 
 const float SPEC_HARDNESS = 256.0;                 // specular highlights hardness
 
+const float BUMP_SUPPRESS_DEPTH = 0.3;             // at what water depth bumpmap will be supressed for reflections and refractions (prevents artifacts at shores)
+
 const vec2 WIND_DIR = vec2(0.5f, -0.8f);
 const float WIND_SPEED = 0.2f;
 
@@ -56,9 +58,9 @@ float fresnel_dielectric(vec3 Incoming, vec3 Normal, float eta)
     return result;
 }
 
-varying vec3  screenCoordsPassthrough;
+varying vec3 screenCoordsPassthrough;
-varying vec4  position;
+varying vec4 position;
-varying float  depthPassthrough;
+varying float depthPassthrough;
 
 uniform sampler2D normalMap;
 
@@ -74,8 +76,18 @@ uniform float near;
 uniform float far;
 uniform vec3 nodePosition;
 
+float frustumDepth;
+
+float linearizeDepth(float depth)  // takes <0,1> non-linear depth value and returns <0,1> linearized value
+  {
+    float z_n = 2.0 * depth - 1.0;
+    depth = 2.0 * near * far / (far + near - z_n * frustumDepth);
+    return depth / frustumDepth;
+  }
+
 void main(void)
 {
+    frustumDepth = abs(far - near);
     vec3 worldPos = position.xyz + nodePosition.xyz;
     vec2 UV = worldPos.xy / (8192.0*5.0) * 3.0;
     UV.y *= -1.0;
@@ -147,32 +159,37 @@ void main(void)
 
     fresnel = clamp(fresnel, 0.0, 1.0);
 
+#if REFRACTION
+    float normalization = frustumDepth / 1000;
+    float depthSample = linearizeDepth(texture2D(refractionDepthMap,screenCoords).x) * normalization;
+    float depthSampleDistorted = linearizeDepth(texture2D(refractionDepthMap,screenCoords-(normal.xy*REFR_BUMP)).x) * normalization;
+    float surfaceDepth = linearizeDepth(gl_FragCoord.z) * normalization;
+    float realWaterDepth = depthSample - surfaceDepth;  // undistorted water depth in view direction, independent of frustum
+ 
+    float shore = clamp(realWaterDepth / BUMP_SUPPRESS_DEPTH,0,1);
+#else
+    float shore = 1.0;
+#endif
     // reflection
-    vec3 reflection = texture2D(reflectionMap,  screenCoords+(normal.xy*REFL_BUMP)).rgb;
+    vec3 reflection = texture2D(reflectionMap, screenCoords+(normal.xy*REFL_BUMP*shore)).rgb;
 
     // refraction
 #if REFRACTION
-    vec3 refraction = texture2D(refractionMap,  screenCoords-(normal.xy*REFR_BUMP)).rgb;
+    vec3 refraction = texture2D(refractionMap, screenCoords-(normal.xy*REFR_BUMP*shore)).rgb;
 
     // brighten up the refraction underwater
     refraction = (cameraPos.z < 0.0) ? clamp(refraction * 1.5, 0.0, 1.0) : refraction;
 #endif
-
     // specular
     vec3 R = reflect(vVec, normal);
     float specular = pow(max(dot(R, lVec), 0.0),SPEC_HARDNESS) * shadow;
 
     vec3 waterColor = WATER_COLOR;
     waterColor = waterColor * length(gl_LightModel.ambient.xyz);
-#if REFRACTION
-    float refractionDepth = texture2D(refractionDepthMap, screenCoords-(normal.xy*REFR_BUMP)).x;
-    float z_n = 2.0 * refractionDepth - 1.0;
-    refractionDepth = 2.0 * near * far / (far + near - z_n * (far - near));
-    
-    float waterDepth = refractionDepth - depthPassthrough;
 
+#if REFRACTION
     if (cameraPos.z > 0.0)
-        refraction = mix(refraction, waterColor, clamp(waterDepth/VISIBILITY, 0.0, 1.0));
+        refraction = mix(refraction, waterColor, clamp(depthSampleDistorted/VISIBILITY, 0.0, 1.0));
 
     gl_FragData[0].xyz = mix( mix(refraction,  scatterColour,  lightScatter),  reflection,  fresnel) + specular * gl_LightSource[0].specular.xyz;
 #else