From bebee39768c5932fef4a92bbdebc83c9b4a4caff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?W=C5=82adys=C5=82aw=20Kuczerenko?=
 <w.kuczerenko@crehler.com>
Date: Fri, 28 Jun 2024 15:44:20 +0200
Subject: [PATCH] Rewrite spheres render logic

---
 zadanie-5/main.cpp | 43 ++++++++++++++++++++++---------------------
 1 file changed, 22 insertions(+), 21 deletions(-)

diff --git a/zadanie-5/main.cpp b/zadanie-5/main.cpp
index dc73219..69cf478 100644
--- a/zadanie-5/main.cpp
+++ b/zadanie-5/main.cpp
@@ -21,6 +21,8 @@ const float initialSpeed = 5.0f;
 const float initialAngle = 45.0f;
 const float ballRadius = 0.5;
 
+const int numberOfPointsOnCircle = 120;
+
 const int windowWidth = 1920;
 const int windowHeight = 800;
 
@@ -395,31 +397,30 @@ void rungeKuttaStep(Ball &ball, float dt) {
 }
 
 void setupSphereBuffer() {
-    int slices = 20;
-    int stacks = 20;
-    std::vector<float> vertices;
 
-    for (int i = 0; i <= stacks; ++i) {
-        float V = i / (float) stacks;
-        float phi = V * M_PI;
+    std::vector<glm::vec3> vertices;
 
-        for (int j = 0; j <= slices; ++j) {
-            float U = j / (float) slices;
-            float theta = U * (M_PI * 2);
+    float angle = 360.0f / numberOfPointsOnCircle;
 
-            float x = cosf(theta) * sinf(phi);
-            float y = cosf(phi);
-            float z = sinf(theta) * sinf(phi);
+    int triangleCount = numberOfPointsOnCircle - 2;
 
-            vertices.push_back(x * ballRadius);
-            vertices.push_back(y * ballRadius);
-            vertices.push_back(z * ballRadius);
+    std::vector<glm::vec3> temp;
+    // positions
+    for (int i = 0; i < numberOfPointsOnCircle; i++)
+    {
+        float currentAngle = angle * i;
+        float x = ballRadius * cos(glm::radians(currentAngle));
+        float y = ballRadius * sin(glm::radians(currentAngle));
+        float z = 0.0f;
 
-            // Dodanie normalnych wektorów
-            vertices.push_back(x);
-            vertices.push_back(y);
-            vertices.push_back(z);
-        }
+        temp.push_back(glm::vec3(x, y, z));
+    }
+
+    for (int i = 0; i < triangleCount; i++)
+    {
+        vertices.push_back(temp[0]);
+        vertices.push_back(temp[i + 1]);
+        vertices.push_back(temp[i + 2]);
     }
 
     glGenVertexArrays(1, &VAO_SPHERES);
@@ -428,7 +429,7 @@ void setupSphereBuffer() {
     glBindVertexArray(VAO_SPHERES);
 
     glBindBuffer(GL_ARRAY_BUFFER, VBO_SPHERES);
-    glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(float), vertices.data(), GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(glm::vec3), vertices.data(), GL_STATIC_DRAW);
 
     // Współrzędne wierzchołków
     glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);