Implement frustum culling (WIP)

src/kekengine/cpp/common/engine.cpp

@@ -198,7 +198,7 @@ int start() {
 			glm::mat4 view = kekData.activeCamera->transformationMatrix();
 
 			glm::mat4 projection;
-			projection = glm::perspective(glm::radians(90.0f), kekData.screenWidth / (float) kekData.screenHeight, KEK_CAMERA_NEAR, KEK_CAMERA_FAR);
+			projection = glm::perspective(glm::radians(KEK_CAMERA_FOV), kekData.screenWidth / (float) kekData.screenHeight, KEK_CAMERA_NEAR, KEK_CAMERA_FAR);
 
 			glm::vec3 position = kekData.activeCamera->getPosition();
 
@@ -279,7 +279,10 @@ int start() {
 			}
 
 			Timer drawTimer;
-			kekData.activeScene->draw(kekData.shader);
+
+			Frustum frustum = getActiveCamera()->getFrustum((float) kekData.screenHeight / kekData.screenWidth);
+
+			kekData.activeScene->draw(kekData.shader, frustum);
 			timings.renderTime = drawTimer.elapsedSeconds();
 		}
 
@@ -292,7 +295,7 @@ int start() {
 		int time = (int) (glfwGetTime() * 10);
 		if(time != prevTime) {
 			int fps = (int) floor(1.0f / kekData.lastTimings.frameTime);
-			std::string str = "FPS: " + std::to_string(fps) + " (" + formatSeconds(kekData.lastTimings.frameTime) + ")" + " | Physics: " + formatSeconds(kekData.lastTimings.physicsTime) + ", Lighting: " + formatSeconds(kekData.lastTimings.lightingTime) + ", Render: " + formatSeconds(kekData.lastTimings.renderTime) + ", Idle: " + formatSeconds(kekData.lastTimings.idleTime);
+			std::string str = "FPS: " + std::to_string(fps) + " (" + formatSeconds(kekData.lastTimings.frameTime) + ")" + " | Physics: " + formatSeconds(kekData.lastTimings.physicsTime) + ", Lighting: " + formatSeconds(kekData.lastTimings.lightingTime) + ", Render: " + formatSeconds(kekData.lastTimings.renderTime) + ", Swap: " + formatSeconds(kekData.lastTimings.swapTime);
 			fpsText->setText(str);
 		}
 		prevTime = time;
@@ -305,11 +308,11 @@ int start() {
 		glDisable(GL_BLEND);
 		glEnable(GL_DEPTH_TEST);
 
-		Timer idleTimer;
+		Timer swapTimer;
 		// Swap buffers and poll window events
 		glfwSwapBuffers(kekData.window);
 		glfwPollEvents();
-		timings.idleTime = idleTimer.elapsedSeconds();
+		timings.swapTime = swapTimer.elapsedSeconds();
 
 		timings.frameTime = frameTimer.elapsedSeconds();
 		kekData.lastTimings = timings;

src/kekengine/cpp/object/gameobject.cpp

@@ -11,6 +11,7 @@ namespace kek {
 
 GameObject::GameObject() {
 	this->physics = nullptr;
+	this->boundingVolume = nullptr;
 }
 
 GameObject::~GameObject() {
@@ -21,9 +22,12 @@ GameObject::~GameObject() {
 
 void GameObject::addMesh(Mesh *mesh) {
 	meshes.push_back(mesh);
+	boundingVolume = mesh->createBoundingVolume(); // TODO: move somewhere else
 }
 
-void GameObject::draw(Shader *shader) {
+void GameObject::draw(Shader *shader, const Frustum &frustum) {
+	if(boundingVolume && !boundingVolume->isContained(frustum, getPosition(), getRotation())) return;
+
 	glm::mat4 model = glm::mat4(1.0f);
 	model = glm::translate(model, getPosition()) * glm::mat4_cast(getRotation());
 	glUniformMatrix4fv(glGetUniformLocation(kekData.shader->id, "model"), 1, GL_FALSE, glm::value_ptr(model));

src/kekengine/cpp/object/scene.cpp

@@ -26,9 +26,9 @@ void Scene::removeObject(GameObject *object) {
 	}
 }
 
-void Scene::draw(Shader *shader) {
+void Scene::draw(Shader *shader, const Frustum &frustum) {
 	for(GameObject *obj : objects) {
-		obj->draw(shader);
+		obj->draw(shader, frustum);
 	}
 }
 

src/kekengine/cpp/render/camera.cpp

@@ -8,11 +8,25 @@
 #include <glm/gtx/matrix_decompose.hpp>
 #include <math.h>
 
+#include "constants.h"
 #include "object.h"
 #include "utils.h"
 
 namespace kek {
 
+float Plane::getDistance(glm::vec3 point) const {
+	return glm::dot(point, normal) - distance;
+}
+
+bool Frustum::contains(glm::vec3 point) const {
+	return near.getDistance(point) >= 0 && far.getDistance(point) >= 0 && left.getDistance(point) >= 0 && right.getDistance(point) >= 0 && top.getDistance(point) >= 0 && bottom.getDistance(point) >= 0;
+}
+
+bool SphereBoundingVolume::isContained(const Frustum &frustum, glm::vec3 position, glm::quat rotation) {
+	glm::vec3 point = position + offset;
+	return frustum.near.getDistance(point) >= -radius && frustum.far.getDistance(point) >= -radius && frustum.left.getDistance(point) >= -radius && frustum.right.getDistance(point) >= -radius && frustum.top.getDistance(point) >= -radius && frustum.bottom.getDistance(point) >= -radius;
+}
+
 Camera::Camera() {
 	this->position = glm::vec3(0.0f, 0.0f, 0.0f);
 	this->direction = glm::vec3(0.0f, 0.0f, -1.0f);
@@ -125,4 +139,25 @@ void Camera::applyEuler(glm::vec3 euler) {
 	roll = euler.z;
 }
 
+Frustum Camera::getFrustum(float aspect) {
+	float halfW = KEK_CAMERA_FAR * tanf(glm::radians(KEK_CAMERA_FOV * 0.5f));
+	float halfH = halfW * aspect;
+	glm::vec3 farPoint = KEK_CAMERA_FAR * direction;
+
+	float rollRad = glm::radians(roll);
+	float x = sin(rollRad);
+	float y = cos(rollRad);
+	glm::vec3 up = glm::vec3(x, y, 0.0f);
+	glm::vec3 cameraRight = glm::normalize(glm::cross(direction, up));
+	glm::vec3 cameraUp = glm::normalize(glm::cross(cameraRight, direction));
+
+	Plane near = Plane(position + KEK_CAMERA_NEAR * direction, direction);
+	Plane far = Plane(position + farPoint, -direction);
+	Plane left = Plane(position, glm::cross(farPoint + cameraRight * -halfW, cameraUp));
+	Plane right = Plane(position, glm::cross(cameraUp, farPoint + cameraRight * halfW));
+	Plane top = Plane(position, glm::cross(farPoint + cameraUp * halfH, cameraRight));
+	Plane bottom = Plane(position, glm::cross(cameraRight, farPoint + cameraUp * -halfH));
+	return Frustum(near, far, top, bottom, left, right);
+}
+
 }

src/kekengine/cpp/render/mesh.cpp

@@ -1,5 +1,6 @@
 #include "mesh.h"
 
+#include "camera.h"
 #include "constants.h"
 
 #include <GL/glew.h>
@@ -90,4 +91,12 @@ void Mesh::draw(Shader *shader) {
 	glBindVertexArray(0);
 }
 
+BoundingVolume *Mesh::createBoundingVolume() {
+	float maxDist = 0;
+	for(Vertex v : vertices) {
+		maxDist = glm::max(maxDist, glm::length(glm::vec3(v.pos.x, v.pos.y, v.pos.z)));
+	}
+	return new SphereBoundingVolume(glm::vec3(0), maxDist);
+}
+
 }

src/kekengine/include/camera.h

@@ -2,10 +2,64 @@
 
 #include <glm/glm.hpp>
 
+#include "glm/geometric.hpp"
 #include "object.h"
 
 namespace kek {
 
+class Plane {
+	glm::vec3 normal;
+	float distance;
+
+  public:
+	Plane(glm::vec3 normal, float distance)
+		: normal(glm::normalize(normal)),
+		  distance(distance){};
+
+	Plane(glm::vec3 point, glm::vec3 normal)
+		: normal(glm::normalize(normal)),
+		  distance(glm::dot(this->normal, point)){};
+
+	float getDistance(glm::vec3 point) const;
+};
+
+struct Frustum {
+	const Plane near;
+	const Plane far;
+	const Plane top;
+	const Plane bottom;
+	const Plane left;
+	const Plane right;
+
+	Frustum(Plane near, Plane far, Plane top, Plane bottom, Plane left, Plane right)
+		: near(near),
+		  far(far),
+		  top(top),
+		  bottom(bottom),
+		  left(left),
+		  right(right){};
+
+	bool contains(glm::vec3 point) const;
+};
+
+class BoundingVolume {
+  public:
+	virtual bool isContained(const Frustum &frustum, glm::vec3 position, glm::quat rotation) = 0;
+};
+
+class SphereBoundingVolume: public BoundingVolume {
+  private:
+	glm::vec3 offset;
+	float radius;
+
+  public:
+	SphereBoundingVolume(glm::vec3 offset, float radius)
+		: offset(offset),
+		  radius(radius) {}
+
+	virtual bool isContained(const Frustum &frustum, glm::vec3 position, glm::quat rotation);
+};
+
 class Camera: public DefaultObject {
 
   public:
@@ -38,6 +92,8 @@ class Camera: public DefaultObject {
 	glm::vec3 eulerAngles();
 
 	void applyEuler(glm::vec3 euler);
+
+	Frustum getFrustum(float aspect);
 };
 
 }

src/kekengine/include/constants.h

@@ -20,6 +20,7 @@
 
 #define KEK_NOCLIP_SPEED 10.0f
 
+#define KEK_CAMERA_FOV 90.0f
 #define KEK_CAMERA_NEAR 0.1f
 #define KEK_CAMERA_FAR 100.0f
 

src/kekengine/include/gameobject.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "camera.h"
 #include "mesh.h"
 #include "object.h"
 #include "physics.h"
@@ -12,6 +13,7 @@ class GameObject: public DefaultRotateableObject {
 
   protected:
 	std::vector<Mesh *> meshes;
+	BoundingVolume *boundingVolume;
 
   public:
 	PhysicsObjectData *physics;
@@ -23,7 +25,7 @@ class GameObject: public DefaultRotateableObject {
 	// Adds a mesh to the GameObject. The GameObject takes ownership of the Mesh, so don't use Meshes in multiple GameObjects
 	void addMesh(Mesh *mesh);
 
-	void draw(Shader *shader);
+	void draw(Shader *shader, const Frustum &frustum);
 
 	void addPhysics(btCollisionShape *shape, float mass, int collisionFlags = 0);
 

src/kekengine/include/mesh.h

@@ -6,6 +6,7 @@
 #include <memory>
 #include <vector>
 
+#include "camera.h"
 #include "shader.h"
 #include "texture.h"
 
@@ -44,6 +45,8 @@ class Mesh {
 	~Mesh();
 
 	void draw(Shader *shader);
+
+	BoundingVolume *createBoundingVolume();
 };
 
 }

src/kekengine/include/scene.h

@@ -2,6 +2,7 @@
 
 #include <vector>
 
+#include "camera.h"
 #include "gameobject.h"
 #include "light.h"
 
@@ -24,7 +25,7 @@ class Scene {
 	void removeObject(GameObject *object);
 
 	// Draws the scene
-	void draw(Shader *shader);
+	void draw(Shader *shader, const Frustum &frustum);
 };
 
 }

src/kekengine/include/timings.h

@@ -12,7 +12,7 @@ struct Timings {
 	float physicsTime = 0;
 	float lightingTime = 0;
 	float renderTime = 0;
-	float idleTime = 0;
+	float swapTime = 0;
 };
 
 class Timer {