working lod

src/Application.cpp

@@ -205,7 +205,7 @@ void Application::run()
 		// TEST CODE
 		glEnable(GL_DEPTH_TEST);
 		glEnable(GL_CULL_FACE);
-    	glCullFace(GL_FRONT);
+    	glCullFace(GL_BACK);
 
 		if (!m_pauseLod)
 			pl->tick(m_camera, deltaTime);

src/planet/Planet.cpp

@@ -62,6 +62,7 @@ void Planet::tick(Camera* camera, GLfloat dtime)
 	{
 		m_faces[i]->tick(camera, dtime);
 	}
+	// m_faces[FACE_TOP]->tick(camera, dtime);
 	// m_faces[FACE_BACK]->tick(camera, dtime);
 }
 
@@ -81,7 +82,7 @@ void Planet::connectFaces()
   m_faces[FACE_RIGHT]->connect(BOTTOM, m_faces[FACE_BOTTOM]);
 }
 
-glm::mat4 Planet::getTransformation()
+const glm::mat4 Planet::getTransformation()
 {
 	glm::mat4 newMat = glm::mat4(1.0f);
 	newMat = glm::translate(newMat, m_position);

src/planet/Planet.h

@@ -36,7 +36,7 @@ class Planet
 		inline PlanetFace* getFace(const unsigned int face) { return m_faces[face]; }
 		PlanetIndexBuffer* getIndexBuffer(const unsigned int detailTop, const unsigned int detailRight, const unsigned int detailBottom, const unsigned int detailLeft);
 
-		glm::mat4 getTransformation();
+		const glm::mat4 getTransformation();
 	private:
 		void connectFaces();
 

src/planet/PlanetFace.cpp

@@ -2,33 +2,22 @@
 #include <time.h>
 #include <math.h>
 
-// Correlates directly to Face enum
+PlanetFaceNode::PlanetFaceNode(
-const glm::vec3 FACE_NORMALS[6] = {
+	PlanetFace* face,
-	// FACE_FRONT
+	PlanetFaceNode* parent,
-	glm::vec3(0.0f, 0.0f, -1.0f),
+	const unsigned int index
-	// FACE_LEFT
+) :
-	glm::vec3(-1.0f, 0.0f, 0.0f),
+	m_planetFace(face),
-	// FACE_BACK
+	m_quadrant(index),
-	glm::vec3(0.0f, 0.0f, 1.0f),
+	m_level(parent ? parent->m_level + 1 : 0),
-	// FACE_RIGHT
+	m_generated(false),
-	glm::vec3(1.0f, 0.0f, 0.0f),
+	m_dirty(true),
-	// FACE_TOP
+	m_leaf(true),
-	glm::vec3(0.0f, 1.0f, 0.0f),
+	m_parent(parent),
-	// FACE_BOTTOM
+	m_children(),
-	glm::vec3(0.0f, -1.0f, 0.0f)
+	m_neighbors(),
-};
+	neighborDetailDifferences()
-
-PlanetFaceNode::PlanetFaceNode(PlanetFace* face, PlanetFaceNode* parent, glm::vec3 position, const unsigned int index) :
-	m_planetFace(face), m_pos(position), m_index(index), m_level(parent ? parent->m_level + 1 : 0), m_generated(false),
-	m_dirty(true), m_leaf(true), m_parent(parent), m_children(), m_neighbors(), neighborDetailDifferences()
 {
-	glm::vec3 normal = face->getNormal();
-
-	// normal 0 1 0    left 1 0 0    forward 0 0 -1
-	// normal 0 0 -1   left 0 -1 0   forward -1 0 0
-	m_left = glm::vec3(normal.y, normal.z, normal.x);
-	m_forward = glm::cross(normal, m_left);
-
 	generate();
 }
 
@@ -192,8 +181,12 @@ const PlanetFaceNode* PlanetFaceNode::getEqualOrHigherNeighbor(const unsigned in
 {
   // Find the youngest ancestor with a neighbor in the given direction
   for (const PlanetFaceNode *node = this; node != 0; node = node->m_parent)
+	{
     if (node->m_neighbors[side])
+		{
       return node->m_neighbors[side];
+		}
+	}
   return 0;
 }
 
@@ -203,7 +196,7 @@ void PlanetFaceNode::findNeighbor(const unsigned int side)
   if (!m_neighbors[side] && m_parent && m_parent->m_neighbors[side])
   {
     // If a valid neighbor is found (child of the parent's neighbor); use it
-    if (PlanetFaceNode *neighbor = m_parent->m_neighbors[side]->m_children[mirrorQuadrant(side, m_index)])
+    if (PlanetFaceNode *neighbor = m_parent->m_neighbors[side]->m_children[mirrorQuadrant(side, m_quadrant)])
       setNeighbor(side, neighbor);
     else
       return;
@@ -220,8 +213,11 @@ void PlanetFaceNode::updateNeighborDetailDifferences(const unsigned int side)
 {
   // Update neighbor detail differences
   for (unsigned int i = 0; i < 4; i++)
-    if (const PlanetFaceNode *neighbor = getEqualOrHigherNeighbor(i))
+	{
+    if (const PlanetFaceNode *neighbor = getEqualOrHigherNeighbor(i)) {
       neighborDetailDifferences[i] = std::min(m_level - neighbor->m_level, (unsigned int)4); // 4 max difference
+		}
+	}
 
   // Force child nodes on the updated side to redraw
   if (!isLeaf())
@@ -244,12 +240,13 @@ unsigned int PlanetFaceNode::getNeighborDetailDifference(const unsigned int side
 
 void PlanetFaceNode::tick(Camera* camera, GLfloat dtime)
 {
-	// TODO: based on planet transform
+	glm::mat4 transform = m_planetFace->getPlanet()->getTransformation();
-	float camToOrigin = glm::distance(camera->getPosition(), (m_planetFace->getPlanet()->getPosition() + m_center));
+	glm::transpose(transform);
+	glm::vec3 campos = glm::vec3(transform * glm::vec4(camera->getPosition(), 1.0f));
+	float camToOrigin = glm::distance(campos, (m_center));
 
 	if (camToOrigin < m_radius * 2.0 && m_leaf) {
 		this->subdivide();
-		return;
 	} else if (camToOrigin > m_radius * 2.0 && !m_leaf) {
 		this->merge();
 		return;
@@ -301,27 +298,22 @@ void PlanetFaceNode::generate()
 	if (m_generated)
 		return;
 
-	std::vector<Vertex> vertices;
+	int vertexCount = RESOLUTION * RESOLUTION;
+	Vertex vertices[vertexCount];
 
-	float divisionLevel = (float)pow(2.0, m_level);
+	float divisionLevel = 1.0f / (float)pow(2.0, m_level);
 	float radius = m_planetFace->getPlanet()->getRadius();
+	float halfRes = (RESOLUTION - 1) / 2.f;
+	glm::vec2 rpos = getPosition();
 	for (int i = 0; i < RESOLUTION; i++)
 	{
 		for (int j = 0; j < RESOLUTION; j++)
 		{
-			// Get the 2D index of the vertex on the plane from zero to one (1 = RESOLUTION - 1)
+			// Get vertex position in the quadtree
-			glm::vec2 index = glm::vec2(i, j) / (RESOLUTION - 1.0f);
+			glm::vec2 treePos = (glm::vec2(i, j) - halfRes) * divisionLevel / halfRes + rpos;
-
+			glm::vec3 vertex = glm::vec3(treePos, 1.0f);
-			// Generate the vertices on the plane using left and forward vectors.
+			// Orient the vertex to the face
-			// here 2 * index - 1 is used to convert 0 - 1 to -1 - 1, that is to
+			vertex = glm::vec3(glm::vec4(vertex, 1.0f) * m_planetFace->getOrientation());
-			// generate the vertices starting from the center point of the unit plane.
-			glm::vec3 iv = (m_forward * (2.0f * index.x - 1.0f)) / divisionLevel;
-			glm::vec3 jv = (m_left * (2.0f * index.y - 1.0f)) / divisionLevel;
-
-			// Add the unit left and forward vectors to the origin, m_pos here
-			// being the center point, which in division level zero is the offset
-			// normal from the center of the cube.
-			glm::vec3 vertex = m_pos + jv + iv;
 
 			// Normalize and multiply by radius to create a spherical mesh (unit sphere)
 			float x2 = vertex.x * vertex.x;
@@ -335,10 +327,16 @@ void PlanetFaceNode::generate()
 
 			// Get noise height and multiply by radius
 			float height = m_planetFace->getPlanet()->getNoise().fractal(8, point.x, point.y, point.z) * 20.0f;
-			glm::vec3 pos = -(height + radius) * point;
+			glm::vec3 pos = (height + radius) * point;
+
+			// Texture coordinate
+			glm::vec2 texCoord = glm::vec2(i, j) / (float)(RESOLUTION - 1);
+			texCoord = texCoord * (1.0f - (1.0f / 128.f)) + 0.5f * (1.0f / 128.f);
 
 			// Add vertex
-			vertices.push_back({ pos, point, glm::vec2(j * (1.0 / RESOLUTION), i * (1.0 / RESOLUTION)) });
+			vertices[INDEX1D(i, j)].position = pos;
+			vertices[INDEX1D(i, j)].normal = point;
+			vertices[INDEX1D(i, j)].uv = texCoord;
 
 			// Set center
 			if ((i == RESOLUTION / 2 && j == RESOLUTION / 2))
@@ -352,21 +350,20 @@ void PlanetFaceNode::generate()
 	glGenBuffers(1, &m_vbo);
 
 	glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
-	glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * vertices.size(), &(vertices[0]), GL_STATIC_DRAW);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * vertexCount, vertices, GL_STATIC_DRAW);
 
   glm::vec3 boundingSphereCenterF = glm::vec3(0.0, 0.0, 0.0);
   float boundingSphereRadiusF = 0.0;
-	int patchVerticesTotal = RESOLUTION * RESOLUTION;
 
   // Calculate mean position and use as bounding sphere center
-  for (int i = 0; i < patchVerticesTotal; i++)
+  for (int i = 0; i < vertexCount; i++)
 	{
     boundingSphereCenterF += vertices[i].position;
 	}
-  boundingSphereCenterF /= (float)patchVerticesTotal;
+  boundingSphereCenterF /= (float)vertexCount;
 
   // Find the largest distance from the center to a vertex
-  for (int i = 0; i < patchVerticesTotal; i++)
+  for (int i = 0; i < vertexCount; i++)
 	{
 		glm::vec3 length = (vertices[i].position - boundingSphereCenterF);
     boundingSphereRadiusF = std::max(boundingSphereRadiusF, glm::dot(length, length));
@@ -381,19 +378,13 @@ void PlanetFaceNode::generate()
 
 bool PlanetFaceNode::subdivide()
 {
-	if (m_level == 10 || !m_planetFace->hasSplitsLeft() || !m_leaf)
+	if (m_level == 8 || !m_planetFace->hasSplitsLeft() || !m_leaf)
 		return false;
 	
-	int lv = m_level + 1;
+	m_children[TOP_LEFT]     = new PlanetFaceNode(m_planetFace, this, TOP_LEFT);
-
+	m_children[TOP_RIGHT]    = new PlanetFaceNode(m_planetFace, this, TOP_RIGHT);
-	// Calculate distance to move the vertices on the unit plane based on division level
+	m_children[BOTTOM_RIGHT] = new PlanetFaceNode(m_planetFace, this, BOTTOM_RIGHT);
-	glm::vec3 stepLeft = m_left * (1.0f / (float)pow(2, lv));
+	m_children[BOTTOM_LEFT]  = new PlanetFaceNode(m_planetFace, this, BOTTOM_LEFT);
-	glm::vec3 stepForward = m_forward * (1.0f / (float)pow(2, lv));
-
-	m_children[TOP_LEFT]     = new PlanetFaceNode(m_planetFace, this, m_pos + stepForward - stepLeft, TOP_LEFT);
-	m_children[TOP_RIGHT]    = new PlanetFaceNode(m_planetFace, this, m_pos - stepForward - stepLeft, TOP_RIGHT);
-	m_children[BOTTOM_RIGHT] = new PlanetFaceNode(m_planetFace, this, m_pos - stepForward + stepLeft, BOTTOM_RIGHT);
-	m_children[BOTTOM_LEFT]  = new PlanetFaceNode(m_planetFace, this, m_pos + stepForward + stepLeft, BOTTOM_LEFT);
 	
 	// Connect the children
 	m_children[TOP_LEFT]->setNeighbor(RIGHT, m_children[TOP_RIGHT]);
@@ -403,8 +394,12 @@ bool PlanetFaceNode::subdivide()
 
 	// Connect neighbors
   for (int i = 0; i < 4; i++)
+	{
     if (m_neighbors[i] && !m_neighbors[i]->isLeaf())
+		{
       m_neighbors[i]->findNeighbor(mirrorSide(i));
+		}
+	}
 
 	// No longer leaf
 	m_leaf = false;
@@ -413,6 +408,10 @@ bool PlanetFaceNode::subdivide()
 
 	return true;
 }
+glm::vec2 PlanetFaceNode::getPosition()
+{
+	return m_parent ? m_parent->getPosition() + glm::vec2(ADJACENT(RIGHT, m_quadrant) ? 1.0 : -1.0, ADJACENT(TOP, m_quadrant) ? 1.0 : -1.0) * (1.0f / (1 << m_level)) : glm::vec2(0.0, 0.0);
+}
 
 bool PlanetFaceNode::merge()
 {
@@ -446,14 +445,26 @@ bool PlanetFaceNode::isLeaf()
 
 glm::vec3 PlanetFaceNode::getAbsolutePosition()
 {
-	return m_planetFace->getPlanet()->getPosition() + m_pos;
+	return m_planetFace->getPlanet()->getPosition();
 }
 
-PlanetFace::PlanetFace(Planet* planet, const unsigned int face) : 
+PlanetFace::PlanetFace(
-	m_planet(planet), m_face(face)
+	Planet* planet,
+	const unsigned int face
+) : 
+	m_planet(planet),
+	m_face(face)
 {
-	m_normal = FACE_NORMALS[m_face];
+	if (face < 4)
-	m_lod = new PlanetFaceNode(this, 0, m_normal, 0);
+	{
+    m_orientation = glm::rotate(glm::mat4(1.0f), (float)((double)face * -0.5 * M_PI), glm::vec3(0.0f, -1.0f, 0.0f));
+	}
+	else
+	{
+    m_orientation = glm::rotate(glm::mat4(1.0f), (float)((face == FACE_BOTTOM ? 0.5 : -0.5) * M_PI), glm::vec3(-1.0f, 0.0f, 0.0f));
+	}
+
+	m_lod = new PlanetFaceNode(this, 0, 0);
 }
 
 PlanetFace::~PlanetFace()

src/planet/PlanetFace.h

@@ -29,6 +29,7 @@ const unsigned int MAX_SPLITS_PER_UPDATE = 2;
 #define MIRROR(s)                       (((s) + 2) % 4)
 #define ADJACENT(s, q)                  ((4 + (q) - (s)) % 4 <= 1)
 #define REFLECT(s, q)                   ((s) % 2 ? ((q) % 2 ? (q) - 1 : (q) + 1) : 3 - (q))
+#define INDEX1D(x, y)                   ((x) + (y) * 17)
 
 struct Vertex
 {
@@ -43,7 +44,7 @@ class PlanetFace;
 class PlanetFaceNode
 {
 	public:
-		PlanetFaceNode(PlanetFace* face, PlanetFaceNode* parent, glm::vec3 position, const unsigned int index);
+		PlanetFaceNode(PlanetFace* face, PlanetFaceNode* parent, const unsigned int index);
 		~PlanetFaceNode();
 
 		void tick(Camera* camera, GLfloat dtime);
@@ -54,6 +55,7 @@ class PlanetFaceNode
 		inline PlanetFace* getPlanetFace() const { return m_planetFace; }
 
 		glm::vec3 getAbsolutePosition();
+		glm::vec2 getPosition();
 
 		inline PlanetFaceNode* getNeighborAt(Direction dir) const { return m_neighbors[dir]; }
 		inline PlanetFaceNode* getChildAt(Quadrant quad) const { return m_children[quad]; }
@@ -80,7 +82,7 @@ class PlanetFaceNode
 		PlanetFaceNode* m_neighbors[4];
     unsigned int neighborDetailDifferences[4];
 
-		unsigned int m_index;
+		unsigned int m_quadrant;
 		unsigned int m_level;
 
 		bool m_dirty;
@@ -90,10 +92,7 @@ class PlanetFaceNode
 		GLuint m_ebo, m_vao, m_vbo;
 		int m_indices;
 
-		glm::vec3 m_pos;
 		glm::vec3 m_center;
-		glm::vec3 m_left;
-		glm::vec3 m_forward;
 		float m_radius;
 };
 
@@ -109,6 +108,7 @@ class PlanetFace
 		inline Planet* getPlanet() const { return m_planet; }
 
 		inline const glm::vec3 getNormal() const { return m_normal; }
+		inline const glm::mat4 getOrientation() const { return m_orientation; }
 		inline PlanetFaceNode* getLODRoot() { return m_lod; }
 
 		inline unsigned int getFace() const { return m_face; }
@@ -121,6 +121,7 @@ class PlanetFace
 		unsigned int m_splits;
 
 		glm::vec3 m_normal;
+		glm::mat4 m_orientation;
 
 		PlanetFaceNode* m_lod;
 };

src/planet/PlanetIndexBuffer.cpp

@@ -29,10 +29,10 @@ PlanetIndexBuffer::PlanetIndexBuffer(
   }
 
   // Build all four edges
-  buildEdge(triangleFans, TOP,  detailLeft);
+  buildEdge(triangleFans, TOP,  detailTop);
-  buildEdge(triangleFans, RIGHT,   detailBottom);
+  buildEdge(triangleFans, RIGHT,   detailRight);
-  buildEdge(triangleFans, BOTTOM,  detailRight);
+  buildEdge(triangleFans, BOTTOM,  detailBottom);
-  buildEdge(triangleFans, LEFT,   detailTop);
+  buildEdge(triangleFans, LEFT,   detailLeft);
 
   // Count the number of triangles and reserve three vertices per triangle
   int triangleCount = 0;