+vector<glm::vec3> quadToTriangles(glm::vec3 *quads) {
+ vector<glm::vec3> triangles(6);
+ triangles[0] = quads[0];
+ triangles[1] = quads[1];
+ triangles[2] = quads[2];
+ triangles[3] = quads[2];
+ triangles[4] = quads[3];
+ triangles[5] = quads[0];
+ return triangles;
+}
+
+template <typename T>
+void append(vector<T> &a, vector<T> &b) {
+ a.insert(a.end(), b.begin(), b.end());
+};
+
+void setupLightBuffers(GLuint progId) {
+ vector<glm::vec3> vertices;
+ glm::vec3 front[] = {
+ glm::vec3(1, -1, -1),
+ glm::vec3(-1, -1, -1),
+ glm::vec3(-1, 1, -1),
+ glm::vec3(1, 1, -1)
+ };
+ vector<glm::vec3> frontTriangles = quadToTriangles(front);
+ append(vertices, frontTriangles);
+
+ glm::vec3 back[] = {
+ glm::vec3(1, 1, 1),
+ glm::vec3(-1, 1, 1),
+ glm::vec3(-1, -1, 1),
+ glm::vec3(1, -1, 1)
+ };
+ vector<glm::vec3> backQuads = quadToTriangles(back);
+ append(vertices, backQuads);
+
+ glm::vec3 top[] = {
+ glm::vec3(1, 1, -1),
+ glm::vec3(-1, 1, -1),
+ glm::vec3(-1, 1, 1),
+ glm::vec3(1, 1, 1)
+ };
+ vector<glm::vec3> topTriangles = quadToTriangles(top);
+ append(vertices, topTriangles);
+
+ glm::vec3 bottom[] = {
+ glm::vec3(1, -1, 1),
+ glm::vec3(-1, -1, 1),
+ glm::vec3(-1, -1, -1),
+ glm::vec3(1, -1, -1)
+ };
+ vector<glm::vec3> bottomTriangles = quadToTriangles(bottom);
+ append(vertices, bottomTriangles);
+
+ glm::vec3 left[] = {
+ glm::vec3(-1, 1, 1),
+ glm::vec3(-1, 1, -1),
+ glm::vec3(-1, -1, -1),
+ glm::vec3(-1, -1, 1)
+ };
+ vector<glm::vec3> leftTriangles = quadToTriangles(left);
+ append(vertices, leftTriangles);
+
+ glm::vec3 right[] = {
+ glm::vec3(1, 1, -1),
+ glm::vec3(1, 1, 1),
+ glm::vec3(1, -1, 1),
+ glm::vec3(1, -1, -1)
+ };
+ vector<glm::vec3> rightTriangles = quadToTriangles(right);
+ append(vertices, rightTriangles);
+ GLuint verticesSize = 36 * 3 * sizeof(GLfloat);
+
+ glGenVertexArrays(1, &lightVao);
+ GLuint vbo;
+ glBindVertexArray(lightVao);
+ glGenBuffers(1, &vbo);
+ glBindBuffer(GL_ARRAY_BUFFER, vbo);
+ glBufferData(GL_ARRAY_BUFFER, verticesSize, NULL, GL_STATIC_DRAW);
+ glBufferSubData(GL_ARRAY_BUFFER, 0, verticesSize, glm::value_ptr(vertices[0]));
+ GLuint posLoc = glGetAttribLocation(progId, "vPosition");
+ glEnableVertexAttribArray(posLoc);
+ glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
+}
+