Add LightStage for rendering lights

libraries/octree/src/ViewFrustum.h

@@ -162,6 +162,7 @@ private:
     // Used to project points
     glm::mat4 _ourModelViewProjectionMatrix;
 };
+using ViewFrustumPointer = std::shared_ptr<ViewFrustum>;
 
 
 #endif // hifi_ViewFrustum_h

libraries/render-utils/src/DeferredLightingEffect.cpp

@@ -69,6 +69,8 @@ void DeferredLightingEffect::init() {
     _allocatedLights.push_back(std::make_shared<model::Light>());
 
     model::LightPointer lp = _allocatedLights[0];
+    // Add the global light to the light stage (for later shadow rendering)
+    _lightStage.addLight(lp);
 
     lp->setDirection(-glm::vec3(1.0f, 1.0f, 1.0f));
     lp->setColor(glm::vec3(1.0f));
@@ -541,10 +543,6 @@ void DeferredLightingEffect::setGlobalLight(const glm::vec3& direction, const gl
     light->setAmbientIntensity(ambientIntensity);
 }
 
-model::LightPointer DeferredLightingEffect::getGlobalLight() {
-    return _allocatedLights[_globalLights.front()];
-}
-
 void DeferredLightingEffect::setGlobalSkybox(const model::SkyboxPointer& skybox) {
     _skybox = skybox;
 }

libraries/render-utils/src/DeferredLightingEffect.h

@@ -21,6 +21,8 @@
 #include "model/Stage.h"
 #include "model/Geometry.h"
 
+#include "LightStage.h"
+
 class RenderArgs;
 struct LightLocations;
 using LightLocationsPtr = std::shared_ptr<LightLocations>;
@@ -50,9 +52,11 @@ public:
     void setGlobalAtmosphere(const model::AtmospherePointer& atmosphere) { _atmosphere = atmosphere; }
     void setGlobalSkybox(const model::SkyboxPointer& skybox);
 
-    model::LightPointer getGlobalLight();
+    const LightStage& getLightStage() { return _lightStage; }
 
 private:
+    LightStage _lightStage;
+
     DeferredLightingEffect() = default;
 
     model::MeshPointer _spotLightMesh;
@@ -72,26 +76,7 @@ private:
     gpu::PipelinePointer _spotLight;
     LightLocationsPtr _spotLightLocations;
 
-    class PointLight {
+    using Lights = std::vector<model::LightPointer>;
-    public:
-        glm::vec4 position;
-        float radius;
-        glm::vec4 ambient;
-        glm::vec4 diffuse;
-        glm::vec4 specular;
-        float constantAttenuation;
-        float linearAttenuation;
-        float quadraticAttenuation;
-    };
-    
-    class SpotLight : public PointLight {
-    public:
-        glm::vec3 direction;
-        float exponent;
-        float cutoff;
-    };
-
-    typedef std::vector< model::LightPointer > Lights;
 
     Lights _allocatedLights;
     std::vector<int> _globalLights;

libraries/render-utils/src/LightStage.cpp

@@ -0,0 +1,79 @@
+//
+//  LightStage.cpp
+//  render-utils/src
+//
+//  Created by Zach Pomerantz on 1/14/2015.
+//  Copyright 2015 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#include "ViewFrustum.h"
+
+#include "LightStage.h"
+
+LightStage::Shadow::Shadow(model::LightPointer light) : _light{ light}, _frustum{ std::make_shared<ViewFrustum>() } {
+    framebuffer = gpu::FramebufferPointer(gpu::Framebuffer::createShadowmap(MAP_SIZE));
+    map = framebuffer->getDepthStencilBuffer();
+}
+
+void LightStage::Shadow::setKeylightFrustum(ViewFrustum* viewFrustum, float zBack, float zFront) {
+    // Orient the keylight frustum
+    const auto& direction = glm::normalize(_light->getDirection());
+    glm::quat orientation;
+    if (direction == IDENTITY_UP) {
+        orientation = glm::quat(glm::mat3(IDENTITY_UP, -IDENTITY_FRONT, IDENTITY_RIGHT));
+    } else {
+        auto side = glm::normalize(glm::cross(direction, IDENTITY_UP));
+        auto up = glm::normalize(glm::cross(side, direction));
+        auto orientation = glm::quat(glm::mat3(direction, up, side));
+    }
+    _frustum->setOrientation(orientation);
+
+    // Position the keylight frustum
+    _frustum->setPosition(viewFrustum->getPosition() - 21.0f * direction);
+
+    _view = _frustum->getView();
+    const Transform viewInverse{ _view.getInverseMatrix() };
+
+    viewFrustum->calculate();
+    //const auto nearCorners = viewFrustum->getCorners(0);
+    const auto nearClip = viewFrustum->getNearClip();
+    const auto nearCorners = viewFrustum->getCorners(nearClip - 1);
+    const auto farCorners = viewFrustum->getCorners(nearClip + 20);
+
+    vec3 min{ viewInverse.transform(nearCorners.bottomLeft) };
+    vec3 max{ min };
+    // Expand keylight frustum  to fit view frustum
+    auto fitFrustum = [&min, &max, &viewInverse](const vec3& viewCorner) {
+        const auto corner = viewInverse.transform(viewCorner);
+
+        min.x = glm::min(min.x, corner.x);
+        min.y = glm::min(min.y, corner.y);
+        min.z = glm::min(min.z, corner.z);
+
+        max.x = glm::max(max.x, corner.x);
+        max.y = glm::max(max.y, corner.y);
+        max.z = glm::max(max.z, corner.z);
+    };
+    fitFrustum(nearCorners.bottomLeft);
+    fitFrustum(nearCorners.bottomRight);
+    fitFrustum(nearCorners.topLeft);
+    fitFrustum(nearCorners.topRight);
+    fitFrustum(farCorners.bottomLeft);
+    fitFrustum(farCorners.bottomRight);
+    fitFrustum(farCorners.topLeft);
+    fitFrustum(farCorners.topRight);
+
+    glm::mat4 ortho = glm::ortho<float>(min.x, max.x, min.y, max.y, -max.z, -min.z);
+    _frustum->setProjection(ortho);
+    _projection = ortho;
+}
+
+const LightStage::LightPointer& LightStage::addLight(model::LightPointer light) {
+    Shadow stageShadow{light};
+    LightPointer stageLight = std::make_shared<Light>(std::move(stageShadow));
+    lights.push_back(stageLight);
+    return stageLight;
+}

libraries/render-utils/src/LightStage.h

@@ -0,0 +1,62 @@
+//
+//  LightStage.h
+//  render-utils/src
+//
+//  Created by Zach Pomerantz on 1/14/2015.
+//  Copyright 2015 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#ifndef hifi_render_utils_LightStage_h
+#define hifi_render_utils_LightStage_h
+
+#include "gpu/Framebuffer.h"
+
+#include "model/Light.h"
+
+class ViewFrustum;
+
+// Light stage to set up light-related rendering tasks
+class LightStage {
+public:
+    class Shadow {
+    public:
+        const int MAP_SIZE = 2048;
+
+        Shadow(model::LightPointer light);
+
+        void setKeylightFrustum(ViewFrustum* viewFrustum, float zBack, float zFront);
+
+        const std::shared_ptr<ViewFrustum> getFrustum() const { return _frustum; }
+        const glm::mat4& getProjection() const { return _projection; }
+        const Transform& getView() const { return _view; }
+
+        gpu::FramebufferPointer framebuffer;
+        gpu::TexturePointer map;
+    protected:
+        model::LightPointer _light;
+        std::shared_ptr<ViewFrustum> _frustum;
+        glm::mat4 _projection;
+        Transform _view;
+    };
+    using ShadowPointer = std::shared_ptr<Shadow>;
+
+    class Light {
+    public:
+        Light(Shadow&& shadow) : shadow{ shadow } {}
+
+        model::LightPointer light;
+        Shadow shadow;
+    };
+    using LightPointer = std::shared_ptr<Light>;
+    using Lights = std::vector<LightPointer>;
+
+    const LightPointer& addLight(model::LightPointer light);
+    // TODO: removeLight
+
+    Lights lights;
+};
+
+#endif