Performance optimization for deciding when the directional shadow gets rendered.

data/shader/phong.fsh

@@ -47,6 +47,7 @@ uniform bool movingTexture;
 uniform vec2 movement;
 uniform vec2 movingTextureOffset;
 uniform float time;
+uniform bool sampleDirectionalShadowSwitch;
 
 vec2 poissonDisk[16] = vec2[](
    vec2( -0.94201624, -0.39906216 ),
@@ -171,40 +172,38 @@ void main()
 
     // direction lighting
     float sunAngle = -1.0;
-    if(length(directionalLightVector)>0.0f) {
+    if(sampleDirectionalShadowSwitch) {
         vec3 directionalVector = normalize(directionalLightVector);
         sunAngle = dot(vec3(0.0, 1.0, 0.0), directionalVector);
-        if ( sunAngle > 0.0) {
+        float directionalVisibility = 1.0f;
-            float directionalVisibility = 1.0f;
+        float directionalIntensity = sunIntensity(sunAngle);
-            float directionalIntensity = sunIntensity(sunAngle);
+        if (distanceToBorder(shadowCoord1.xy) <= 0.5 && distanceToBorder(shadowCoord1.xy) > 0.2) {
-            if (distanceToBorder(shadowCoord1.xy) <= 0.5 && distanceToBorder(shadowCoord1.xy) > 0.2) {
+            if (distanceToBorder(shadowCoord0.xy) <= 0.5 && distanceToBorder(shadowCoord0.xy) > 0.2) {
-                if (distanceToBorder(shadowCoord0.xy) <= 0.5 && distanceToBorder(shadowCoord0.xy) > 0.2) {
+                directionalVisibility = sampleDirectionalShadow(shadowMap_directional0, shadowCoord0, 0.001, directionalIntensity);
-                    directionalVisibility = sampleDirectionalShadow(shadowMap_directional0, shadowCoord0, 0.001, directionalIntensity);
-                }
-                else if (distanceToBorder(shadowCoord0.xy) <= 0.5 && distanceToBorder(shadowCoord0.xy) > 0.0) {
-                    float directionalVisibility0 = sampleDirectionalShadow(shadowMap_directional0, shadowCoord0, 0.001, directionalIntensity);
-                    float directionalVisibility1 = sampleDirectionalShadow(shadowMap_directional1, shadowCoord1, 0.002, directionalIntensity);
-                    directionalVisibility = mix(directionalVisibility0, directionalVisibility1, distanceToBorder(shadowCoord0.xy) * 5);
-                }
-                else {
-                    directionalVisibility = sampleDirectionalShadow(shadowMap_directional1, shadowCoord1, 0.002, directionalIntensity);
-                }
             }
-            else if (distanceToBorder(shadowCoord1.xy) <= 0.5 && distanceToBorder(shadowCoord1.xy) > 0.0) {
+            else if (distanceToBorder(shadowCoord0.xy) <= 0.5 && distanceToBorder(shadowCoord0.xy) > 0.0) {
+                float directionalVisibility0 = sampleDirectionalShadow(shadowMap_directional0, shadowCoord0, 0.001, directionalIntensity);
                 float directionalVisibility1 = sampleDirectionalShadow(shadowMap_directional1, shadowCoord1, 0.002, directionalIntensity);
-                float directionalVisibility2 = sampleDirectionalShadow(shadowMap_directional2, shadowCoord2, 0.01, directionalIntensity);
+                directionalVisibility = mix(directionalVisibility0, directionalVisibility1, distanceToBorder(shadowCoord0.xy) * 5);
-                directionalVisibility = mix(directionalVisibility1, directionalVisibility2, distanceToBorder(shadowCoord1.xy) * 5);
             }
             else {
-                directionalVisibility = sampleDirectionalShadow(shadowMap_directional2, shadowCoord2, 0.01, directionalIntensity);
+                directionalVisibility = sampleDirectionalShadow(shadowMap_directional1, shadowCoord1, 0.002, directionalIntensity);
             }
-            diffuseColor += clamp(dot(normalize(vNormal), directionalVector)
-            *diffuseFactor*directionalIntensity*sunColor(sunAngle), 0.0, 1.0)*directionalVisibility;
-            vec3 cameraVector = normalize(camera - vec3(fragPosition));
-            specularColor += clamp(pow((dot((cameraVector+directionalVector),normalize(vNormal))/
-            (length(cameraVector+directionalVector)*length(normalize(vNormal)))),shininess), 0.0, 1.0)
-            *specularFactor*directionalIntensity*sunColor(sunAngle)*directionalVisibility;
         }
+        else if (distanceToBorder(shadowCoord1.xy) <= 0.5 && distanceToBorder(shadowCoord1.xy) > 0.0) {
+            float directionalVisibility1 = sampleDirectionalShadow(shadowMap_directional1, shadowCoord1, 0.002, directionalIntensity);
+            float directionalVisibility2 = sampleDirectionalShadow(shadowMap_directional2, shadowCoord2, 0.01, directionalIntensity);
+            directionalVisibility = mix(directionalVisibility1, directionalVisibility2, distanceToBorder(shadowCoord1.xy) * 5);
+        }
+        else {
+            directionalVisibility = sampleDirectionalShadow(shadowMap_directional2, shadowCoord2, 0.01, directionalIntensity);
+        }
+        diffuseColor += clamp(dot(normalize(vNormal), directionalVector)
+        *diffuseFactor*directionalIntensity*sunColor(sunAngle), 0.0, 1.0)*directionalVisibility;
+        vec3 cameraVector = normalize(camera - vec3(fragPosition));
+        specularColor += clamp(pow((dot((cameraVector+directionalVector),normalize(vNormal))/
+        (length(cameraVector+directionalVector)*length(normalize(vNormal)))),shininess), 0.0, 1.0)
+        *specularFactor*directionalIntensity*sunColor(sunAngle)*directionalVisibility;
     }
 
     // point lights

game/graphics.cc

@@ -30,6 +30,7 @@ Graphics::Graphics(glm::uvec2 windowSize, float nearPlane,
     renderFlames = true;
     renderWorld = true;
     renderDebug = false;
+    directionalShadowSwitch = false;
 }
 
 Graphics::Graphics() {
@@ -196,6 +197,7 @@ void Graphics::init(Level* level) {
     lightingShader->setUniform("fogColorRise", level->getFogColourRise());
     lightingShader->setUniform("fogColorNight", level->getFogColourNight());
     lightingShader->setUniform("ambientColor", level->getAmbientLight());
+    lightingShader->setUniform("sampleDirectionalShadowSwitch", false);
     if(level->getDirectionalLight()) {
         lightingShader->setUniform("directionalLightVector",
             level->getDirectionalLight()->getPosition());
@@ -361,37 +363,46 @@ void Graphics::render(double time)
                 }
             }
 
-            // render depth textures for sun
-            depthShader->use();
             glViewport(0, 0, windowSize.x, windowSize.y);
-           
+
-            
+            // render depth textures for sun
             float sunAngle = glm::dot(glm::vec3(0.0f, 1.0f, 0.0f), glm::normalize(level->getDirectionalLight()->getPosition()));
             glm::vec3 sunVector = (level->getCameraCenter()->getPosition() + level->getDirectionalLight()->getPosition());
 
-            for (unsigned int i = 0; i<framebuffer_directional.size(); i++) {
+            if (sunAngle > 0.0f) {
-                framebuffer_directional.at(i)->bind(); 
+                if (!directionalShadowSwitch) {
-                glClear(GL_DEPTH_BUFFER_BIT);
+                    lightingShader->use();
-                if (sunAngle > 0.0f) {
+                    lightingShader->setUniform("sampleDirectionalShadowSwitch", true);
-                    float projection_size = 0.0f;
+                    directionalShadowSwitch = true;
-                    switch(i) {
-                        case 0:
-                            projection_size = 10.0f;
-                            break;
-                        case 1:
-                            projection_size = 30.0f;
-                            break;
-                        case 2:
-                            projection_size = farPlane/1.5f;
-                            break;
-                    }
-                    depthViewProjectionMatrices.at(i) =  glm::ortho<float>(-projection_size, projection_size, -projection_size, projection_size, -farPlane/1.5f, farPlane/1.5f) *
-                        glm::lookAt(sunVector, level->getCameraCenter()->getPosition(), glm::vec3(0,1,0));
-                    level->render(depthShader, false, -1, &depthViewProjectionMatrices.at(i));
-                    if (!framebuffer_directional.at(i)->isFrameBufferObjectComplete()) {
-                        printf("Framebuffer incomplete, unknown error occured during shadow generation!\n");
-                    }
                 }
+                depthShader->use();
+                for (unsigned int i = 0; i<framebuffer_directional.size(); i++) {
+                    framebuffer_directional.at(i)->bind();
+                    glClear(GL_DEPTH_BUFFER_BIT);
+                        float projection_size = 0.0f;
+                        switch(i) {
+                            case 0:
+                                projection_size = 10.0f;
+                                break;
+                            case 1:
+                                projection_size = 30.0f;
+                                break;
+                            case 2:
+                                projection_size = farPlane/1.5f;
+                                break;
+                        }
+                        depthViewProjectionMatrices.at(i) =  glm::ortho<float>(-projection_size, projection_size, -projection_size, projection_size, -farPlane/1.5f, farPlane/1.5f) *
+                            glm::lookAt(sunVector, level->getCameraCenter()->getPosition(), glm::vec3(0,1,0));
+                        level->render(depthShader, false, -1, &depthViewProjectionMatrices.at(i));
+                        if (!framebuffer_directional.at(i)->isFrameBufferObjectComplete()) {
+                            printf("Framebuffer incomplete, unknown error occured during shadow generation!\n");
+                        }
+                }
+            }
+            else if (directionalShadowSwitch) {
+                lightingShader->use();
+                lightingShader->setUniform("sampleDirectionalShadowSwitch", false);
+                directionalShadowSwitch = false;
             }
         }
         

game/graphics.hh

@@ -84,6 +84,7 @@ class Graphics {
         bool renderFlames;
         bool renderDebug;
         bool renderWorld;
+        bool directionalShadowSwitch;
         DebugDraw debugDrawer;
         SharedArrayBuffer debug_ab;
         SharedVertexArrayObject debug_vao;