Merge pull request #120 from dos1/agx-fixups

AgX fixups

environment/skydome.cpp

@@ -185,7 +185,7 @@ float CSkyDome::PerezFunctionO2( float Perezcoeffs[ 5 ], const float Icostheta,
 void CSkyDome::RebuildColors() {
 
     float twilightfactor = std::clamp( -simulation::Environment.sun().getAngle(), 0.0f, 18.0f ) / 18.0f;
-    auto gammacorrection = glm::mix( glm::vec3( 0.45f ), glm::vec3( 1.0f ), twilightfactor );
+    auto gammacorrection = glm::mix( glm::vec3( 1.0f ), glm::vec3( 0.45f ), twilightfactor );
 
 	// get zenith luminance
 	float const chi = ( (4.0f / 9.0f) - (m_turbidity / 120.0f) ) * ( M_PI - (2.0f * m_thetasun) );
@@ -211,7 +211,7 @@ void CSkyDome::RebuildColors() {
 
 	// trough all vertices
 	glm::vec3 vertex;
-	glm::vec3 color, colorconverter, shiftedcolor;
+	glm::vec3 color, colorconverter;
 
 	for ( unsigned int i = 0; i < m_vertices.size(); ++i ) {
 		// grab it
@@ -258,9 +258,7 @@ void CSkyDome::RebuildColors() {
 			colorconverter.z = 1.0f - std::exp( -m_expfactor * colorconverter.z );  
 		}
 
-        if( colorconverter.z > 0.85f ) {
+        colorconverter.z = std::pow( std::max( colorconverter.z, 0.0f ), gammacorrection.x );
-            colorconverter.z = 0.85f + ( colorconverter.z - 0.85f ) * 0.35f;
-        }
 
         colorconverter.y = std::clamp( colorconverter.y * Global.m_skysaturationcorrection, 0.0f, 1.0f );
         // desaturate sky colour, based on overcast level
@@ -277,12 +275,10 @@ void CSkyDome::RebuildColors() {
         // this height-based factor is reduced the farther the sun is up in the sky
         float const shiftfactor = std::clamp( std::lerp(heightbasedphase, sunbasedphase, sunbasedphase), 0.0f, 1.0f );
         // h = 210 makes for 'typical' sky tone
-        shiftedcolor = glm::vec3( 210.0f, colorconverter.y, colorconverter.z );
+        glm::vec3 const skytonecolor = colors::HSVtoRGB( glm::vec3( 210.0f, 0.5f, colorconverter.z ) );
-        shiftedcolor = colors::HSVtoRGB( shiftedcolor );
 
-		color = colors::HSVtoRGB(colorconverter);
+        color = colors::HSVtoRGB( colorconverter );
-
+        color = glm::mix( color, skytonecolor, shiftfactor * Global.m_skyhuecorrection );
-        color = glm::mix( color, shiftedcolor, shiftfactor * Global.m_skyhuecorrection );
 
         // crude correction for the times where the model breaks (late night)
         // TODO: use proper night sky calculation for these times instead
@@ -295,10 +291,15 @@ void CSkyDome::RebuildColors() {
             color.y = 0.65f * color.z;
         }
         // simple gradient, darkening towards the top
-        color *= std::clamp( ( 1.0f - vertex.y ), 0.2f, 1.f );
+        color *= std::clamp( ( 1.0f - vertex.y * 0.75f ), 0.0f, 1.f );
+
+        float const horizonboost = 1.5f + m_overcast;
+        float const horizonbandwidth = 0.2f; // boost tapers to 0 by ~11.5 degrees elevation
+        float const horizonband = std::clamp( 1.0f - vertex.y / horizonbandwidth, 0.0f, 1.0f );
+
+        color *= std::lerp( 1.0, horizonboost, horizonband );
+
         //color *= ( 0.25f - vertex.y );
-        // gamma correction
-        color = glm::pow( color, gammacorrection );
         m_colours[ i ] = color;
         averagecolor += color;
         if( ( m_vertices.size() - i ) <= ( m_tesselation * 10 + 10 ) ) {

rendering/opengl33renderer.cpp

@@ -1875,7 +1875,7 @@ void opengl33_renderer::setup_environment_light(TEnvironmentType const Environme
 void opengl33_renderer::setup_sunlight_intensity( float const Factor ) {
 
     m_sunlight.apply_intensity( Factor );
-    light_ubs.lights[ 0 ].intensity = m_sunlight.factor;
+    light_ubs.lights[ 0 ].intensity = m_sunlight.factor * (1.0f - Global.Overcast * 0.33f);
     light_ubs.ambient = m_sunlight.ambient * m_sunlight.factor;
     light_ubo->update( light_ubs );
 }
@@ -2047,7 +2047,7 @@ bool opengl33_renderer::Render(world_environment *Environment)
 		// write cloud color into material
 		TSubModel *mdl = Environment->m_clouds.mdCloud->Root;
 		if (mdl->m_material != null_handle)
-			m_materials.material(mdl->m_material).params[0] = glm::vec4(color, 1.0f);
+			m_materials.material(mdl->m_material).params[0] = glm::vec4(color * 2.5f, 1.0f);
 
 		// render
 		Render(Environment->m_clouds.mdCloud, nullptr, 100.0);

shaders/light_common.glsl

@@ -27,8 +27,8 @@ float metalic = 0.0;
 //                       = sharper terminator (more contrast between
 //                       lit and shaded faces of the same surface).
 // ---------------------------------------------------------------------
-const float AMBIENT_SCALE       = 0.3;
+const float AMBIENT_SCALE       = 0.65;
-const float SUN_DIFFUSE_SCALE   = 0.4;
+const float SUN_DIFFUSE_SCALE   = 1.5;
 const float SUN_NDOTL_SHARPNESS = 1.25;
 
 float length2(vec3 v)

shaders/tonemapping.glsl

@@ -69,12 +69,12 @@ vec3 Agx(vec3 val)
         0.0423756549057051, 0.0784336, 0.879142973793104
     );
 
-    // DEFAULT_LOG2_MIN = -10.0
+    // DEFAULT_LOG2_MIN = -6.0
-    // DEFAULT_LOG2_MAX = +6.5
+    // DEFAULT_LOG2_MAX = +4.5
     // MIDDLE_GRAY = 0.18
     // log2(pow(2, VALUE) * MIDDLE_GRAY)
-    const float min_ev = -12.47393;
+    const float min_ev = -8.47393;
-    const float max_ev = 0.526069;
+    const float max_ev = 2.026069;
     const float agx_eps = 1e-6;
 
     // Input transform (inset)
@@ -99,10 +99,7 @@ vec3 AgxEotf(vec3 val)
     // Inverse input transform (outset)
     val = agx_mat_inv * val;
 
-    // sRGB IEC 61966-2-1 2.2 Exponent Reference EOTF Display.
+    return max(val, vec3(0.0));
-    // If your render target already applies sRGB conversion, replace this with:
-    // return max(val, vec3(0.0));
-    return pow(max(val, vec3(0.0)), vec3(2.2));
 }
 
 vec3 AgxLook(vec3 val)
@@ -124,7 +121,7 @@ vec3 AgxLook(vec3 val)
     // Punchy
     slope = vec3(1.0);
     power = vec3(1.35);
-    sat = 1.4;
+    sat = 1.1;
 #endif
 
     // ASC CDL